# Gemini 105MC Slow speed under power



## TexasWill (Apr 24, 2010)

Greetings,

I am purchasing a 2001 Gemini 105MC. According to other owners website she should get 7 knots under power, but during our sea trial she maxed out at 4.9 knots.

She has the standard westerbeck 27 hp diesel with around 900 hours.

The centerboards were down during the sea trial.

Both instruments and GPS indicated same speed.

She is in Fresh Water (thought this was a factor, but after speaking with another owner on Lake Michigan his boat does go 7 knots under power)

She has a Generator and 2 AC units. (thought this was a factor but the Gen Set is only 295 pounds, and both ACs are under 100) Even with the 2 of us on board and everything extra I could come up with (water, fuel, battery bank, Kayaks), she still had less than 1500 pounds of additional weight.(1100 stuff +400 for 2 people)

The Engine appears by the tachometer to get to full RPMs (3200RPMS) and there is no audible slipping of the engine or transmission.

The boat was capsized in 2005, but did not suffer any hull damage beyond a hole in the side of one hull.

Any theories anyone has to help explain this would be appreciated. I really love the boat, but a 25% knock in performance is unacceptable. I have no idea how to test if she suffers the same performance hit under sail.

The survey is next Tuesday so any thoughts I will relay to the surveyor. Thank you.


-Will


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## pdqaltair (Nov 14, 2008)

* Dirty bottom. it would take over 1/4" to cause that.
* Dirty prop (worse). Would vibrate a lot, but you might not notice without a baseline.
* Engine RPMs. Did it get to full revs?
* Waterline. Is she lower in the water than other 105mcs?

The first is most likely, and it could be that bad. If it is, require that it be cleaned for the survey.


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## TexasWill (Apr 24, 2010)

Thanks for the quick reply pdqaltar

The last bottom job was in Jan 2010, and the bottom is currently clean.

Didn't specifically check the prop. We will check during the survey.

The engine did get to full RPM.

I do not know what the typical waterline is on a gemini, but she did have under the recommended wieght loaded.


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## svHyLyte (Nov 13, 2008)

> The Centerboards were down...


Generally, one only uses a single, leeward, centerboard on a Cat so fitted and particularly a Gemini (having sailed one). With both down you're dragging a lot of extra surface area through the sea and you may have no idea what condition the boards are in.

FWIW...


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## TexasWill (Apr 24, 2010)

I would love that to be the case, The seller did state that he always left the centerboards down, so they could be in rough shape, espicially if they were not cleaned at the same time as the bottom. That is also an easy thing to test and a cheap thing to fix. I didn't think that would create such a large impact on performance.


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## FarCry (Apr 21, 2007)

Is the prop the original? If it was underpropped it would turn full RPMS but not get to full speed. Did you do your speed test in two opposite directions? Where you towing a large dinghy? Could current, big waves or lots of wind have caused the slow indicated speed? The knot meter should negate that if clean and calibrated properly. My guess is that the centerboards the main culprit.


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## TexasWill (Apr 24, 2010)

There was very light wind and slight waves the day of the sea trial. There was nothing being towed. We did run the test in both directions, and there was no current being in a relatively small lake. 

The instruments and GPS both displayed the same speed, so I do believe them to be properly calabrated. 

Thank you all again for your inputs...I am making a list of every possible solution anyone posts to go over with the surveyor, and will post here next week with what we find.

Please keep the ideas coming. 

-Will


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## 2Gringos (Jan 4, 2008)

you pulled the anchor up, right?


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## TexasWill (Apr 24, 2010)

Yep, The anchor was up...nothing was being towed ,drug or dangled.


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## 2Gringos (Jan 4, 2008)

Hmm...well, from a logical point of view, it pretty much has to be the prop, then, doesn't it? Smaller diameter or less pitch than normal?


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## pdqaltair (Nov 14, 2008)

Well, I'm glad you checked the obvious. You asked the right questions.

I don't have a Gemini, but my boat is very similar and I have been around them. 4.9 knots is very slow. That is only about 1/4 horsepower (I can reach that with one engine at ~ 1/2) if everything is right. My top speed is about the same - 7.2 knots with 2 x 9.9 hp.

Under propping seems absurd on a late-model boat... but I don't blame the poster one bit, because those are the things you check when nothing else makes sense. Odd things happen.

Do check the boards carefully. You should be able to hit 7.2 knots boards down - mine don't come up! Additionally, his reason for leaving them down was very lame. The reason folks leave them down is generally because they are jammed and possibly laminated. The factory recommends leaving them up EVERY TIME. They may also be wood and ruined. Check the Gemini site (Yahoo) for opinions, but this is real $$$ or really big DIY effort.

See the picture of me pulling a Seabrake drogue at 4.2 knots!!!!
Sail Delmarva: Drogue and Parachute Sea Anchor Testing: A Summary for Small to Medium Cruising Catamarans. Sail Delmarva: The Merits of Learning to Sail on a Small Boat[/url]. It's GOT to be prop/engine issues.


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## 2Gringos (Jan 4, 2008)

Please let us know what you find. I am very interested, as we are also planning to buy a Gemini 105Mc later this year. In our case it will likely be around October. Third Quarter.


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## SuenosAzules (Apr 11, 2010)

*Owner of a Gemini..*

As a previous owner of a Gemini 105 MC, and reading your posts, I would say to look at these things first: (1) Make sure the prop is the factory prop from Sonic (in the UK). (2) Make sure the engine is maxing at its proper RPM, and if it is not start with the fuel system (Raycor filters, etc). (3) Then depending on the weight of the gear aboard could be causing more drag. If you find out the problem I would love to hear what is was.

On another note, how did the Gemini capsize in 2005? Would love to hear about that as well.


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## TexasWill (Apr 24, 2010)

Thank you all for your input and ideas so far. In summary these are the ideas I have gathered from myself, the seller, the surveyor, and all of you;

Things that could cause the slower speed

1.	Hulls not parallel as a result of the accident
2.	Centerboards dirty or damaged
3.	Transmission slipping
4.	Prop smaller diameter or less pitch (non-factory)
5.	Something on the prop causing it to wobble or damage to the prop
6.	Dirty/old fuel causing less HP

Things that have been ruled out

1.	Boat is over weight (It is carrying about 800 pounds of extras, but only 2 of us were on board) 
2.	Slower speed due to less buoyancy in fresh water (verified with Gemini owner in Lake Michigan this is a non-factor)
3.	Engine not reaching full RPMs (Tac read 3200 RPMs)
4.	Instruments being faulty (GPS Confirmed)
5. Bottom Dirty (owner stated bottom was recently cleaned however will be double checked with Haul Out)

This is not hypothetical, nor a trick question...it is a real world example of a problem that I hope together we can solve.


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## davidpm (Oct 22, 2007)

Any chance someone upgraded the alternator or added some belts to drive something to suck down HP?


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## FSMike (Jan 15, 2010)

If the engine is reaching full rpm then the horsepower is adequate. With the boards up, if the speed is still lacking, it pretty much has to be a propellor problem or trans slipping since you say the bottom is clean and you are discounting weight as a factor. You might consider having a mechanic use a test tach to verify that yours is accurate, but that's grasping at straws. I have to admit that I would be tempted to offload everything I and a few strong friends could carry and then see what happens.
Good luck.


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## bljones (Oct 13, 2008)

Is the tach accurate? I know that some Yanmars, for instance, will read up to 500 rpm high. Did it FEEL like 3200 rpm?
If it's making the revs, then fuel is not the problem.
Prop, clutch or a lying tach are the possibilities that come to mind.


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## 2Gringos (Jan 4, 2008)

Have you tried raising the boards at all? If they are able to be raised up into their cases, then a flattened or splayed board is probably not a culprit.

Did the boat "pull" to one side at all, or does it feel balanced and symmetrical tracking straight, etc?


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## pdqaltair (Nov 14, 2008)

2Gringos said:


> Have you tried raising the boards at all? If they are able to be raised up into their cases, then a flattened or splayed board is probably not a culprit.
> 
> Did the boat "pull" to one side at all, or does it feel balanced and symmetrical tracking straight, etc?


While I expressed concern about why the boards were left down and the possible results, I doubt they could slow the boat so much. As I indicated, I could make 4.2 knots with a big drogue.

It is also possible (probable?) that it is several of the suggested causes and one more that we have not thought of.


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## johnferrell (Feb 1, 2009)

*flotation chambers*

You might want to check the flotation chambers. I believe there are four. These have been known to fill up and it could add hundreds if not thousands of pounds to the boat. They can fill up from with rain or lake water depending where the leak might be. It is known problem with the gemini. I think the 105 has leaks from the rudder compartment that can go into the floation chambers. The gemini yahoo website is a good source of info for the known problems and fixes of all of the Gemini saiboats
john ferrell
B "SEA" NU
#161


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## 2Gringos (Jan 4, 2008)

Looking at any photo online of a Gemini afloat ( and there are many thousands) it should be pretty easy to see about where the waterline should be. If this one is so heavy as to cut the speed almost in half, wouldn't it be near awash?

All four corners would have to be equally flooded in order not to put some kind of a list on the boat, wouldn't that be highly unlikely?

And if the boat were flooded to that extent, it would sail really really badly, too, wouldn't it? Problem would not be engine specific.

I wouldn't call a handful of leaking float chamber issues a big problem out of a thousand hulls. It's something to check, all right, but a few people having issues and talking about them over and over and over on the internet would lead one to believe that these things fill up and sink right out of the factory.

None of the other 990 owners bother to write in and say that _their _boat is floating just fine.


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## TexasWill (Apr 24, 2010)

I went over the pictures I took of the boat and the bottom paint is clearly visable 3-4 inches above the waterline all around the boat. There is also serveral inches between the bottom paint and the aft steps. So judging from that the boat is not sitting low in the water, nor is it overwieght. 

The seller seemed the type to take miticulous care of his boat, there were no signs of neglect. Everything that was visable looked strait off the showroom. 

He did mention the chambers, so I know he knew they existed, but we did not check them during the sea trial...we will definitly give them a look during the survey. 

We did raise and lower the centerboards, but we did so while at the dock, before we were underway.

Thanks again to everyone reading and posting.

-Will


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## 2Gringos (Jan 4, 2008)

seems to keep coming back to the drivetrain or prop, doesn't it.


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## davidpm (Oct 22, 2007)

Another thought is to check the repair records for anything that has been fixed, improved. Some change may have had an unintended problem.

You seem to have checked all the normal stuff, at this point your imagination goes wild.

Making sure the RPM you see is the RPM you get would be a good place to start.

An upgrade to the transmission gearing? I'm reaching here.
It will sure be interesting when you find it.
Has anyone had a prop with damage that they just ground down to hide it? An inch off the tip would cause something. Really reaching!!!


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## pdqaltair (Nov 14, 2008)

davidpm said:


> Another thought is to check the repair records for anything that has been fixed, improved. Some change may have had an unintended problem.
> 
> You seem to have checked all the normal stuff, at this point your imagination goes wild.
> 
> ...


The owner is present, he seems to have maintained the boat well... and he doesn't KNOW the reason? Fishy.

7.2 vs. 4.9 knots is huge. 2/3rds of the power is missing.

You never mentioned - no sailing during the sea trial? A sea trial without a good breeze should be canceled until there is one.


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## chucklesR (Sep 17, 2007)

I have Gemini #987. I make 7 knts at 3000rpm. I routinely leave a board down as it helps with maneuvering, that's not it.

Raising boards might give me a 1/4 knots. 
Make sure you raise them at survey just to make sure they work - it's a half day each of labor to re-rig them, and rebuilding is a bear.

If you made 3200 rpm as full throttle that is low, the engine is rated at 3600 and should make that with the normal 15x12 propeller. 
Raise the drive leg and let the engine go to full rpm, pull out the manual and confirm my unloaded rpm memory - 3850. 
Water is from the seacock in the starboard hull, there is no overheat danger running the engine with the leg up (and you want to test the pump / leg anyway).

If the boat capsized, and I'd love to hear that story, then the engine might be unable to deliver full power, and the propeller was changed to FOOL a buyer who wasn't paying attention to rpm vs speed. To my knowledge only 3 Gem's have capsized, all while being chartered bare boat. If that was a charter boat that 900 hours is a lie.

A Gemini with that weight loaded on it should float with at least one inch of hull between the water line and the two white drain holes from the rudder locker, check that - then take a torpedo (small) level and check for trim fore and aft. She could be low in the bow, or low in the stern.

If the flotation chambers where full you'd be WAyyyyy down in the water - that's over 2000 pounds even fresh. It would also be very noticeable if just one were flooded.

Almost all Gemini's list to port about 1 degree when no one is onboard - that's the battery weight. A 2001 105MC hull will have 1 inch of immersion per 450 pounds per hull (900 pounds to the inch if you load her exactly even).
Walking from one side to the other should rock the boat in her slip.

If the hulls are out of alignment that's a whole different problem and a walk away boat. I presume it would need lasers to determine that from the outside but a survey would find twisted bulkheads and beams. She'd also leak like a sieve because her deck would be warped.

Good luck - get the story on the capsize and shoot me a PM please. 
If you need more input / feedback try the yahoo group or you can find me at Anything Sailing Forum - same username, I'm a moderator over there.


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## TexasWill (Apr 24, 2010)

We did sail during the sea trial, but I know there are far to many variables during sailing to be able to tell if we were going any slower than I would have expected. To the best of my knowledge we at about 45 degrees into the wind. The wind was about 9-11 knots, and we were sailing 3-4 knots. Then we tacked switching the wind off the port side (still at 45 degrees) and kept the same speed. Then we motored back. 

We did wind the engine up to 3500 RPMs , but she didn't sound like she liked it very much, and it did get us right at 5 knots. This was a very brief period (maybe 20 seconds) the rest of the time it was 3200RPMs and 4.8 knots or 2700RPMs pushing us at about 4 knots. 

To be honest, I don't care much if it is a fault with the engine becuase I don't plan to use it much...but if the performance hit was something wrong with the boat that affected the boat likewise under sail, then it would be a major issue.

The boat was never chartered and was capsized by the current owner in the lake she is in now. He said he was used to sailing monohulls and it got away from him. He showed me the $78,000 in reciepts and the post accident survey and eveything seemed on the up and up. 

She is a perferct boat for me and my family, and I really want everything to work out. I really want us to find out the issue next tuesday and you all are helping very much.


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## bljones (Oct 13, 2008)

TexasWill said:


> To be honest, I don't care much if it is a fault with the engine becuase I don't plan to use it much..


I planned to marry a billionaire virgin nymphomaniac.
Funny how things don't work out the way you plan.

look, if this was a $5000 investment, and this was a 9.9 hp outboard that was clapped out, then I'd agree- ignore it. But it ain't.

This is serious money. In some parts of North America, that same money you spend on a Gemini would buy you a very nice house on an acre of land.
Would you pay the same amount for that house if the furnace didn't work, the electrical system was only 80 volts, or you only had cold water? Of course not.

It sounds like you fell in love with the boat. That's good- if you don't love her, she won't love you back. But that doesn't mean you need to get stupid.

if everything else checks out, hold back $5k, and/or, require the seller to have the engine diagnosed and repaired as a condition of sale.


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## TexasWill (Apr 24, 2010)

bljones said:


> if everything else checks out, hold back $5k, and/or, require the seller to have the engine diagnosed and repaired as a condition of sale.


I agree completely...If we find out what is wrong, I will definitely expect the seller and I to come to some kind of financial agreement on what it will take to make it right. My only fear is that we will not find out what it the issue is.


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## MMR (Oct 5, 2007)

> To be honest, I don't care much if it is a fault with the engine becuase I don't plan to use it much...but if the performance hit was something wrong with the boat that affected the boat likewise under sail, then it would be a major issue.


I'm not an engine expert, but it seems to me that there are serious problems if you can't make more than 5 knots w/o the engine complaining.

While I know that you intend to sail and not motor much, you need to consider that if you need power NOW and FAST to get yourself and your family out of trouble, its not the sails that you will turn to, its the motor.

Consider the summer storm that blows up suddenly as you are 1/2 way on your way home. You HAVE to drop sails because the storm looks severe. You bettered have full confidence in your motor to keep the boat facing into the storm and steady through gusts pushing the hulls around. 5 kts, straining, on a nice day, AIN'T GOING TO CUT IT.

Sounds like you love the boat. I know we love ours, but rethink the motor issue. You and your family's safety WILL rely on it. There are other Gemini's out there....

EDIT: Another point that hubby just mentioned; the engine also provides power via the alternator for battery charging, etc that could be compromised or less efficient if the motor is underpowered or damaged in some way. Just one more reason to track down exactly what is going on......


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## chucklesR (Sep 17, 2007)

TexasWill said:


> To the best of my knowledge we at about 45 degrees into the wind. The wind was about 9-11 knots, and we were sailing 3-4 knots. Then we tacked switching the wind off the port side (still at 45 degrees) and kept the same speed. Then we motored back.


It is not just the motor then, it's a deeper issue.

9-11 kts of wind close hauled should get you 6 kts or better. 
This isn't me bragging on my boat, this is the very real performance expectations.
This is a polar chart done up by one of the owners (_Isis_) - a owner who is well regarded, an aeronautical engineer, and a personal acquaintance of mine. I have tested it to the limit of my ability and the winds - it's real.










The example given is a good one - at 40 degrees apparent and 12 kts of TRUE wind you can and should expect 7.3 kts of boat speed, clean bottom, decent sails and proper trim a given. 
I've topped 10 kts in 16 true, GPS and log confirmed, including photo's on this forum- and I'm loaded to cruise, dinghy, AC etc. 
Three weeks ago, with a 15 month old bottom paint job my Admiral (MMR posting above) and I topped 6.5 kts in 12kts apparent - "light" loaded, no dinghy on the davits, no bedding, light liquids on board.

The polar uses jib and main - Isis doesn't have a screecher. I was using mine when I busted 10 knots, but not in the example above.

I am not aware of a lake capsized Gemini by an owner. I'd appreciate it if you PM'd me the name and hull number - I don't ask for me; there is a club called the Gemini Gem's, which consists of many of the owners. We'd like to know the story as it is pertinent to us (any Gem's story of a capsize is good to us for information purposes).

78k in receipts for a 2001? That is a seriously large amount of repairs for a Gemini. I paid 145k for mine new in 2007 (More with options -23k in add ons - 168 total). Current base price is 192k. 
_One Note_, a 105M sank at the pier under snow this year 5 miles from my slip, it was totaled for less than that. Just saying.

I don't want to spook your deal, if you like the boat you like the boat. I love mine, minus some quality control issues. 
I was told there was a Gemini thread here with some speed issues, figured I'd present some info.


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## 2Gringos (Jan 4, 2008)

the repair invoices didn't have any line items for 'ballast', did they?

Is there a way to measure draft, or freeboard? what else but excess weight or incredible drag could make it that slow under both power and sail?
One big honking barnacle?

I would be extremely interested in knowing where I can find info on the bareboat charter capsizes. We have our first charter on one in a few weeks. 

What does it take to flip one of these? Not reefing enough and tripping on a centerboard?


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## chucklesR (Sep 17, 2007)

2Gringo's,

To my understanding, one flipped in San Diego two years ago. A bareboat skipper, wife and child onboard, no injuries.
He was going downwind in 25 knots, full sail and screecher - pulled in sails to gybe and turned 90 degrees (broad side on) with sails tight; and got hit by a 4 foot wake at the same time. 

To flip one you have to get one hull up past 19 degrees (it leaves the water at 18 degrees of heel). At that point you have wind under the hull. If you do nothing you will go over. 
By the chart above, that takes full sail in 28 knots of true wind 90 degrees off the wind and the sails have to be in tight so the pressure does not bleed off as speed (i.e., all heeling force). 

Testing at PCI says at 85 degrees it will come back down right side up, if there is no wind. Ha. 

I've sailed mine close hauled in 22 kts with jib and main full. I was heeled about 6 degrees; I took a reef in the jib by 1/3 and leveled out to 3 degrees and gained 3 knots of speed. 
The designer recommends no more than 7 degrees of heel should be allowed. 

Following the reefing points - most importantly - on a catamaran you reef for the gusts not the steady wind. To be clearer, if the forecast is 15-20 an gusts to 25, you reef as if it's all 25 (first in jib, first in main for certain, 2nd in jib if you are going to wind). 

And you always mind your heel. It's a skinny cat. Skinniest one on the market. 40 foot mono's have the same beam.
4 are circumnavigating, many have crossed the pond. 
No boat is safe in unsafe hands.


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## sailingdog (Mar 19, 2006)

I'd point out that the hulls can't be misaligned unless the bridgedeck was severely damaged and they had to re-join the two hulls to some degree. The two hulls and the bridgedeck's lower half are made in a single mold AFAIK, and the deck is a single mold as well.


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## smackdaddy (Aug 13, 2008)

Hey chuckles! Sup dude?

I drove a Corsair 31 this weekend. Freakin' fast. 17 knots downwind with a screecher (Code 0).


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## TexasWill (Apr 24, 2010)

I may have had the wind speed mixed up( to be honest I wasn't really looking at the instruments that closely) but armed with your chart I am sure we can get some very accurate readings this tuesday. Thanks, chuckles, I now feel confiedent that between myself and the surveyor we will be able to tell if anything is wrong under sail. I feel much better already. 

How hard is it to achieve these speeds? Are these expected speeds or maximums? How much of a margin could be generated by sails not properly trimed or any other error a novice sailer may make?


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## chucklesR (Sep 17, 2007)

Smacky : life is good - kudo's on the B.S ad 

TexasWill:

Polar charts are projections of performance based on getting it right. Racing skippers use them to set goals. The maker of that chart gave permission to use it (copyright) but not the full write up. A reasonably skilled and attentive skipper with reasonably not blown sails and reasonably loaded boat should get within 10% or so. 
If in the example of 12 kts true you aren't making 7.3kts and instead make 6.5 I'd call it a good day. BUT it should make at least 6kts.

Suffice it to say, the sails are 9 years old, the skipper is a factor (familiarity etc). The standing rigging needs tuning etc.. it's not a racing boat.

10kts true should get you 6; Point up, trim, then fall off to a reach. *If I can't make 2/3 of wind speed on a lazy haul at 60* off I've had too much Rum or there is a bikini nearby.

My demo sail sold me on the boat, 6 kts of wind outside Annapolis; main and screecher we made 4kts at 35 off the wind. Sailed a circle around a schooner that was slapping and flapping trying to make enough way to turn.

One other note, this might help with fairness of helm. The boat should balance out with almost no weather or lee helm at all. If she has rudder position indicators on the auto helm note them - sailing hard into the wind should be one bar on the indicator, no more. 
If it doesn't have a indicator all is not lost: pop the rudders up and eyeball center, put a piece of tape on the wheel. Hard into the wind should be no more than 1/3 turn of the wheel. 
I can almost always play the sails and get neutral helm. 
Heck you can sail totally using the traveler to turn the boat if you want and know how. I do it all the time (sitting on the hammock).
You should pop up the rudders anyway just to check that both are tracking.


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## sailingdog (Mar 19, 2006)

One possible problem that can be an issue is if the rudders aren't parallel to each other. That can cause severe drag and slow the boat considerably. You really want to check that the rudders are aligned with each other. If work was done to the boat's steering system, this could easily have been screwed up and not checked.


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## TexasWill (Apr 24, 2010)

We had the Survey yesterday and it did include a haul out. The bottom was spotless, the centerboards and rudders we all in good shape and aligned. The surveyor measured and poked and said there was nothing wrong with the hull that could cause the slowness. I did get some measurements under sail. The surveyor said the rigging was very loose, and that may account for the slow speed under sail, but here they are;

90 degrees, 12 knots of true wind. 5.2 knots boat speed
70 degrees, 10 knots of true wind. 5 knots boat speed

We tested with a portable Tac and the engine was matching up with the instrument reading.

2000 RPM 3.3 knots
3000 RPM 4.7 knots
3600 RPM 5.2 knots

We also tried to get a read from the portable tac on the back side of the transmission, but the measurements were all over the place, and over half the time that tac didn't even read. We are thinking this means the transmission is slipping, but we need to get an engine surveyor to verify it. Thoughts?

-Will


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## kd3pc (Oct 19, 2006)

Will 

we looked at the Gemini very closely and did quite a bit of sailing on them...something is VERY WRONG with this boat...your surveyor, unless he has looked at TONS of 105s is not going to discover what is wrong with this one.

it should not be that slow...under sail or power.. Even with a rookie like me it should easily do 6-8 with 12knts of wind...

You have been given lots of reasons to walk away, I would do so - there are plenty of 105s out there that will sail circles around this one and probably be a dream to live with.

Your call, but please don't let the time/survey/lust get in the way of the facts...this boat is not right.


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## sailingdog (Mar 19, 2006)

Did they replace the prop on the boat??? The Gemini's I've been on do about 6 knots or so at 3000 RPM IIRC. 

Loose rigging could account for the poor performance under sail...


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## 2Gringos (Jan 4, 2008)

Is there a way to find someone who is an expert on that Sonic drive leg, and ask them if there is anything mechanical in there that could slip and still be operational?

Hmm....can you turn the prop without turning the engine?


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## sailingdog (Mar 19, 2006)

The sonic drive leg is a pretty basic beastie... I took one apart last December to re-build it... It is basically just gears, shafts and a universal joint type mechanism. Either it works or it doesn't. If it doesn't, it is because some of the gears are busted or missing teeth.


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## T34C (Sep 14, 2006)

TexasWill said:


> We did sail during the sea trial, but I know there are far to many variables during sailing to be able to tell if we were going any slower than I would have expected. To the best of my knowledge we at about 45 degrees into the wind. The wind was about 9-11 knots, and we were sailing 3-4 knots. Then we tacked switching the wind off the port side (still at 45 degrees) and kept the same speed. Then we motored back.
> 
> We did wind the engine up to 3500 RPMs , but she didn't sound like she liked it very much, and it did get us right at 5 knots. This was a very brief period (maybe 20 seconds) the rest of the time it was 3200RPMs and 4.8 knots or 2700RPMs pushing us at about 4 knots.
> 
> ...


Chuckles- Correct me if I'm wrong, but should you be able to sail faster that 3-4 kts in 9 -11 kts of wind? I can do better than that in my 37 year old monohull.


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## ebs001 (May 8, 2006)

Something is definitly wrong. The RPMs appear to be right maxing at 3600 no load and 3300 under load. The prop is therefore the correct one or you won't get these readings. So it's not the motor and it's not the prop something else is slowing the boat down. Two knots is significant and the fact that speed through the water and speed over ground are the same means it has something to do with how the boat is going through the water. Something is holding it back. You have ruled out a dirty bottom. The dagger boards will slow you down a bit (someone posted maybe a 1/4 knot) but not 2. The only other variable that I can see is how much wetted surface the boat has. So how does it's freeboard does this Gemini and how does that compare to others?


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## T34C (Sep 14, 2006)

With this unknown issue affecting the boat, why would you continue to even consider this. There are lots of Gemini's out there, if you really want to buy one why not look for another that hasn't flipped and doesn't have issues like this.

I have a sneaking idea the hull is toast. Why take the chance?


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## TexasWill (Apr 24, 2010)

All, 

Thank you very much for you inputs...I have sent the seller and my broker the following e-mail:

"I have reach the difficult decision to withdrawal my bid for "XXXXX" based on her inability to achive the expected cruising speed under power. I do not feel it is my responsibility as a buyer to pay for engine surveyor and mechanics to travel to fix a problem on a boat which I do not own. I have invested over $1000.00 in the boat for survey expenses, haul out charge, and 3 trips to see her, and think it is best to cut my looses. I do not want to pay another $300-$400 to get someone to look at the engine and transmission when that may or may not be the case. Not to mention what could be $1,000's in repairs.

I love the boat, but the bottom line is there are many more boats that fit my needs just as well, and this was just has to big of a questions mark. I apologize and wish you the best of luck in selling the boat. I know you have others in line behind me. I would be glad to sell my survey to any prospective buyer for 1/2 my cost of survey and haul out($375.00). 

If the boat is repaired and the other buyers do not pan out, I would consider putting in a different offer

-Will"

How many licks does it take to get to the tootsie roll center of a toorsie roll pop? The world may never know!


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## Fstbttms (Feb 25, 2003)

No need to apologize or explain yourself to the broker. He's the one trying to foist damaged goods on you. He wasn't doing you any favors.


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## davidpm (Oct 22, 2007)

I'm disappointed. I was looking forward to finding out what the problem was.


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## 2Gringos (Jan 4, 2008)

Me too.


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## Pau Hana Daz (Oct 28, 2007)

Based on the description/info, I'm going to guess that this is hull #723.

If it is (and it sounds like it to me) - She's listed on Yachtworld for about 20% less than others in her age range.


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## davidpm (Oct 22, 2007)

This is a long shot but could their be some flexing of the hull going on that would kill the speed?


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## rustyrusty (Mar 28, 2010)

*Slow 105Mc*

I must be a bit slow too ive been looking at this boat for the last week and cant get the broker to send me any info after I asked why it had new rigging he wont answer my calls. Has anyone found out what is wrong with it?? I would love to know but thanks for all posting I was just ging to travel half way around the world to repeat the same disapointing process..
Rusty in Brisbane.


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## therapy23 (Jul 28, 2007)

I wanted to know too.

I was going to say look at the rudders but I guess you got it all looked at.

Mine pretty much follows the polar chart..........if I pay attention.  

Oh well.

Best of luck in your search.

PS If anyone finds out the real deal please let us know.


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## therapy23 (Jul 28, 2007)

PPS

Thanks for the polars chuckles.


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## rustyrusty (Mar 28, 2010)

*Slow 105Mc*

I just got a line from the Droker and he said this Boat has a 12' visor on the front windows and this and the stac pac could be what is slowing the boat down I have seen a lot of these boats with asun visor on the front windows any one got any thoughts on this.


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## kd3pc (Oct 19, 2006)

yeah sure it is the stack pack....

get real...why are you even looking at this boat...??


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## rustyrusty (Mar 28, 2010)

*105Mc slow*

25000 reasons why im still looking at it. But I am also concerned that there might be some long term problems with it being under water like corosion in parts that are not easy to get to. Lots of bits not made to ever be in that much water they might start to corrode and give trouble. Im not sure if this would be an ongoing problem with this boat. I have emailed the builders they must have an interest in this problem it must be in there interest to get find out what it is.


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## sww914 (Oct 25, 2008)

I'm thinking- upside down boat, water everywhere, rust in the cylinders, low compression, down on HP, slow boat. Maybe it ran for a couple of minutes upside down with no oil pressure? Just a worn out engine now. Pure speculation, but that's my theory. We'll probably never know now.


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## rustyrusty (Mar 28, 2010)

*slow 105Mc*

Something is definitly wrong. The RPMs appear to be right maxing at 3600 no load and 3300 under load. The prop is therefore the correct one or you won't get these readings. So it's not the motor and it's not the prop something else is slowing the boat down. Two knots is significant and the fact that speed through the water and speed over ground are the same means it has something to do with how the boat is going through the water. Something is holding it back. You have ruled out a dirty bottom. The dagger boards will slow you down a bit (someone posted maybe a 1/4 knot) but not 2. The only other variable that I can see is how much wetted surface the boat has. So how does it's freeboard does this Gemini and how does that compare to others?
That has been covered I think in this... The broker told me it was only 1/2 a knot they got up to 5.5knots he said extra weight on the boat and the wind loading of the 12' sun shade on the front windows and the lower buoyancy of the fresh water ??? not sure about that I thought it would mean the boat would sit lower in the water and that would be the reason. It would be slower but pic show it isnt sitting lower in the water. I would expect a bit more from a surveyor than what has happened. I would like to know what he thought about it.


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## kd3pc (Oct 19, 2006)

the broker is trying to sell the boat...read the older responses, this boat ought to scream...all that broker stuff is crap.

The builder will have NO interest in "fixing" this, someone else chose to fix it, when it should have been scrapped. The builder only offers a one year warranty to start with, why would they volunteer to fix someone else's screwup.

Just be glad that previous lookers have uncovered this problem, and it is a problem, defective repair or some such.

Run away from this broker and this boat, neither are honest about this boat. Talk to Performance Cruising or test sail one of their new boats.


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## chucklesR (Sep 17, 2007)

therapy23 said:


> PPS
> 
> Thanks for the polars chuckles.


My pleasure.

Hope you have as much fun living up to them as I do. It's not easy, but it is possible.


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## chucklesR (Sep 17, 2007)

Rusty, 
If you are in Brisbane, save your travel dollars for a closer Gem and take it out for a sail. 
Less buoyancy because of fresh water causing a speed reduction? BS. 
Ask for a measurement from water to top of deck at the center most stanchion, starboard side and PM it to me. I'll take mine the same place today. 
I'm cruise loaded as heavy as I get, half load on water and fuel right now. I'm showing 3 inches of original black bottom paint above the water amidships, less aft because of my dinghy, and full lockers aft (extra batteries on port side yada yada). My stbd cabin is remodeled as a pantry with 200 lb plus of pots, pans, soda's, and food. Port cabin is general storage, 200 lb plus of chairs, tables, grill, and various stuff. I carry a lot of extra back aft; I'd balance it out but prefer the bow to be light so I don't bury it in a power boat wake.

I'll repeat, flat water, no wind, 7.2 knots at full RPM - did that just last weekend. 2800 rpm; 6.0 to 6.2 knots depending on wave and wake.
Not 5.5

I'm not trying to kill the sale of this Gem, it's probably still a sound boat. My thought is the hulls got out of alignment when it capsized and that is slowing it down, or - having given it a lot of thought:

Gemini's aren't exactly built to high standards. There is a lot on non-encapsulated, non-sealed wood used in the construction. A capsize would have soaked it - it might be wet and heavy. It's been years, it might have twisted when drying. Other than weighing the boat when empty I don't know how to check that - and weight can vary. PCI says either 8,600 or 9,600 depending on who you ask.

It's a lot of might. I'm not a surveyor.

If you want to reach me, best way in on Anything Sailing Forum


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## thesnort (Jun 2, 2007)

Rusty, I'm guessing you're in Brisbane, Australia and not Brisbane, CA. In any event, in either location, this is a Gemini too far. The transportation costs would be very high.


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## stuartbell (Nov 14, 2004)

*Achieve Boat Speed*

My Gem will not achieve full boat speed with the boards down. Raise the boards and see how you do.

How are you measuring boat speed? The speed log is a worthless instrument for measuring speed, it only is useful for attracting grass and growth. If you are using the GPS, you must average the speed in both directions to achieve a true reading.

/Stu


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## 2Gringos (Jan 4, 2008)

While I would dearly love to find out what is going on with this particular Gemini.....I would have to add my vote to haul butt to some other Gemini without any mysteries.


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## FunInTheSun (Jul 6, 2010)

We were planning to head up to check this boat out. It is only four hours from us and I was excited to find a freshwater boat. I'm glad we found this post to hear the true story about the boat. The broker told me that it was caught in high winds on the lake and a few shrouds were damaged, he also said that the hull had a small gouge from hauling the boat out. Not that it was completely capsized and had a hole in the hull. The broker is a liar. Like everyone else said steer clear. I guess it is back to the boat search for us.


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## svHyLyte (Nov 13, 2008)

If the yacht was flipped and had hull damage, I wonder if the bridge deck might also have ben torqued up. If the hulls are out of alignment, the boat will move through the water something akin to the way a vehicle with a bent frame "sidewinds" down the road. It wouldn't take much misalignment to induce extraordinary drag between the hulls--ergo, reduced speed capability.

FWIW...


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## therapy23 (Jul 28, 2007)

FunInTheSun said:


> We were planning to head up to check this boat out. It is only four hours from us and I was excited to find a freshwater boat. I'm glad we found this post to hear the true story about the boat. The broker told me that it was caught in high winds on the lake and a few shrouds were damaged, he also said that the hull had a small gouge from hauling the boat out. Not that it was completely capsized and had a hole in the hull. The broker is a liar. Like everyone else said steer clear. I guess it is back to the boat search for us.


I'm 40 hours away.


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## QuickMick (Oct 15, 2009)

is this boat on lake ray roberts? if it is it is on my dock. pm me if you have questions and ill share with you what i know.


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## QuickMick (Oct 15, 2009)

First off I believe that the boat may have been bluewater _before_ being moved to fresh. From what I hear, yes she was _fully_ capsized on the lake when a storm blew up under too much sail. Fully capsized she fried (from what i hear) all of the electronics. dunno about any mech. damage. that being said, the owner does take meticulous care of her. again, i have not heard this from the owner, but from residents of the lake so some of the facts may have gotten distorted over time. I believe she is called the 'Winddancer'


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## ElaS (Jul 14, 2010)

*I was eyeing that boat too!*

Not that I am as ready to buy a boat quite yet, but I started looking already to have a sense of what's out there, and how the boat market moves. I may be getting more serious buying in a few months.

Thank you for sharing the saga, and thanks everyone who helped.

I too am seriously in love with 34' Gemini 105M, even though I haven't sailed one yet, only read accounts of those who had and seen pics of every nook and cranny from every angle.

They cost bit more than I was hoping to spend (and this one was of course so much cheaper, ha!), and I imagine I may end up spending still more to do some necessary modifications and mayb add equipment I desire. I am actually contemplating a partnership with an individual or a couple, to share ownershop and sail together.


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## QuickMick (Oct 15, 2009)

If anyone is still interested I learned that the Gemini sold. 100even.


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## kd3pc (Oct 19, 2006)

Someone has been hoodooed, as we say in SW VA....

Too bad they had not seen all the information presented here. There is something major wrong with the boat...surveyor didn't notice...insurance company may have grounds to not pay...

Oh well...


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## QuickMick (Oct 15, 2009)

watch out for that hoodoo voodoo.... thanks kd3pc, i just learned a new word!!


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## aferlazzo (Jul 7, 2005)

As someone who is a potential future Gemini owner, I hope the specific problem with the subject boat is eventually identified and the cause of the problem determined. I fear the new owner may be stuck with a boat that has a very serious flaw.

Does anyone recall what the asking price on the listing was? It appears the listing is no longer on yachtworld.


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## Pau Hana Daz (Oct 28, 2007)

QuickMick said:


> If anyone is still interested I learned that the Gemini sold. 100even.


The boat in question is still showing on Yachtworld as available: (2001 Gemini 105-M Sail Boat For Sale - www.yachtworld.com.

The recent Gemini sale for $100,000 is a different vessel (Pat's Cat in AL).


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## QuickMick (Oct 15, 2009)

the owner is from whom i got the information, dont know a much better source than that...unless (which i have no idea why anyone would) made it up, or the contract fell through.... i believe orig. ask (again info from owner) was 105


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## QuickMick (Oct 15, 2009)

also, i dont know how quickly yachtworld removes listings, or if they possibly wait until delivery so as not to have to repost if something falls through...
i just called the yacht world broker, he said under contract last week, done deal


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## Pau Hana Daz (Oct 28, 2007)

I stand corrected. Still curious about the speed issue - Wonder if the buyer found the cause.


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## therapy23 (Jul 28, 2007)

DWJensen said:


> I stand corrected. Still curious about the speed issue - Wonder if the buyer found the cause.


Send em over to the Yahoo Gemini site.

Everyone there is helpful.


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## Pau Hana Daz (Oct 28, 2007)

It was brought up there a few weeks/months back.


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