# Harken MK-IV Furler - What I like...



## Maine Sail (Jan 6, 2003)

Hi All,

Last spring I installed the new Harken MK-IV furler. It was a brand new model so I did not want to be premature with a one season review. Well, after a full season, all be it short compared to many in warmer climes, we have put about 2100nm on it with zero issues. It has worked flawlessly and it installed easily.

One feature I really like is the ability to keep and have access to a head stay turnbuckle.

This is how user friendly the Harken MK-IV really is:

*Step one: Loosen these four bolts and pop the retainer plate out off the corresponding notch on the foil (you do not need to take them all the way out, just loose, a NICE feature to prevent losing the bolts):*








*Step two:** Remove this pin and slide the drum up the foil and snug down the previous four screws to hold the drum up and out of the way:*








*Step 3: Adjust your turnbuckle! Yes it's that easy!!!*









*P.S. The ONLY thing I do NOT like about this unit is the CRAPPY furler line it comes with!! Harken are you listening? This has been a MAJOR complaint with just about everyone I know who owns a MK-IV. This black line with red tracer SUCKS!!!*


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## Faster (Sep 13, 2005)

We're into our first season with this furler.. installed it over the winter. So far no problems either, but at this point we are using it strictly as a furler, not a reefer.

Definitely agree with Hal re: the supplied furling line - a replacement is on the list. It would be nice to see Harken respond to this complaint.


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## Maine Sail (Jan 6, 2003)

*We reef..*



Faster said:


> We're into our first season with this furler.. installed it over the winter. So far no problems either, but at this point we are using it strictly as a furler, not a reefer.
> 
> Definitely agree with Hal re: the supplied furling line - a replacement is on the list. It would be nice to see Harken respond to this complaint.


We are using ours to reef and it works great. It seems to keep a decent furled head sail shape too. Highest winds reefed so far have only been in the high 30's..


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## Rockter (Sep 11, 2006)

It looks well-built there Hal.
On the Shaeffer, it's diffilcult to get to the turnbuckle.


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## Maine Sail (Jan 6, 2003)

Rockter said:


> It looks well-built there Hal.
> On the Shaeffer, it's diffilcult to get to the turnbuckle.


Schaefer's are well built but not as user friendly and surprisingly more expensive. I had one, Schaefer 2100, on my old Catalina and it worked great but when it came time to buy a new one the Harken had had features and price!


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## labatt (Jul 31, 2006)

We've got a Harken Mk IV and it seems to "slip". We have two reef marks on our genoa. We'll reef to the second reef, and after a couple of hours it will "slip" to the first reef. Here's what our rigger said when I asked him to look into it:
_
The new Harken furlers have a really nice independent tack swivel- the extrusions rotate with the drum, but the tack is free to spin until the luff 'catches up' with it. I think when furling, the sail is rolling up ok and leaving the tack behind (as it should) to flatten the sail during reefing. But, later on with more wind, the sail rolls tighter and tighter giving the result of more turns needing to be added. It would appear that it is slipping, but it is really just getting a tighter roll on the extrusions. Does this make sense?

In short, it is working fine but you may need to pre-roll a few more turns than you think necessary to accomodate this tightening.
_
Personally, I don't like the fact that my sail slips in heavy wind.


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## T37Chef (Oct 9, 2006)

*Agreed*

Our new Harken Unit 2 Mk IV installed July 2007 has been working flawlessly. Everything halekai36 said I would agree with 100%. It is that easy, when I moved the line to the port side I had to adjust the drum, easy and took less then 2 minutes!

One note, I should have raised the height of the drum due to the proximity to the anchor & roller, otherwise love it!

BTW...I inquired with Harken about the crappy furling line and was very pleased with how they reacted to my inquiry...here is their response (I removed names & email addresses and start at the bottom which is my original email, the others are the replies from Harken!

*******************************************************
Hi Michelle, our customer Shawn is one of about 20 who have complained about the line. It was developed to be as strong as the old MkIII line but smaller in diameter and less expensive.fficeffice" /><O></O>
I think it is time that we get our salesperson from Yale Cordage to give us a visit to talk about our customers concerns. Please set up a meeting within the next month.<O></O>
Thanks Michelle and thank you Shawn for contacting us about this problem.<O></O>
<O> </O>
Greg 
Senior Engineer - Furling Technical Manager

Harken Inc.
<O></O>
<O></O>



​
*Sent:* Wednesday, January 23, 2008 10:06 AM
*To:* Shawn
*Cc:* 
*Subject:* RE: Unit 2 Line<O></O>

<O> </O>
Shawn,<O></O>
Please let me know how this proceeds as adjustments are employed. Customer feedback both positive and negative can be a very useful tool for improvement. Thanks again.<O></O>
Jim,<O></O>
<O> </O>
Jim 
Tech Service Group Leader<O></O>
<O></O>
Harken Inc.<O></O>

<O> </O>
*From:* Shawn 
*Sent:* Tuesday, January 22, 2008 6:17 PM
*To:* Jim 
*Cc:* ffice:smarttags" /><?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com







Dan </st1ersonName>
*Subject:* RE: Unit 2 Line<O></O>

<O> </O>
Jim,<O></O>
<O></O>
Thank you very much for taking the time to answer my question and explain the rational behind the line chosen. I should have clarified that my main grip with the line is the grip it doesn't have. Being a cruiser most of the time, I don't wear gloves, I feel a line sold on a cruising furler should be easier to grip, especially when wet  

Nonetheless, I will be sure to regularly check everything you advised me too.<O></O>
<O></O>
Regards,
Shawn<O></O>
<O></O>
<O></O> 
<O></O>
<O></O> 
<O></O>
<O></O>
-----Original Message-----
*From:* Jim 
*Sent:* Tuesday, January 22, 2008 3:23 PM
*To:* *Cc:* <st1ersonName w:st="on">Dan </st1ersonName>
*Subject:* FW: Unit 2 Line<O></O>
<O></O>
Shawn,<O></O>
Good after noon, sorry to hear of your dissatisfaction with our choice of the furling line used in the new MK1V and cruising furlers. On the other hand I am happy to hear the kind words regarding the performance, construction and design of our units, thank you for that. I would like to answer your question about the choice of line and offer a couple of ideas that may help you better manage the headsail furling line. For many years we sold a double braided Dacron line with the furler as the furling line. It was selected for its strength value and a size diameter that could be easily hung onto with the assistance of the ratchet installed as the last block in the lead block system. When the manual furling redesign came along we looked at all of the options available and tested dozens of materials, constructions and diameters from well known cordage manufactures while staying within the strength limitations we needed to meet. I was involved with that testing. We tested some stiff lines, some flexible lines, double braded and single braided lines and we even tested a line with two distinct different diameters in the same length of cordage much like a tapered line. We set and furled and set and furled all day, changed the line out, make notes and move onto the next line. At the end of the exercise we found that there was very little difference in performance between these very different lines, they all worked very well. When it was all said and done we decided on a single/solid braid line which was slightly smaller than the double braided line we replaced. The single braided line is stronger than the line we used to use and just a hair smaller in diameter with approximately the same hand hold and feel. <O></O>
Having explained all of that. There are a couple of things in the rig that can cause difficulty furling. The most common are a halyard that has too much tension on it causing excessive friction in the ball races in the halyard swivel and not enough tension on the head stay which will also make things more difficult. If you feel that the head stay is even a little to slack put a couple of turns on the turnbuckle body and slack the halyard .250" or .375" and try it again. There should always be a ratchet used in the furling line lead block system and the ratchet should be mounted at the furthers location aft. The line should lead aft through the ratchet and then back forward covering as much of 180-degrees of the sheave as possible. The way this works is that hauling out on the sheet to set the sail automatically charges the furling line back onto the spool as the sail sets. As the sail sets it drags the furling line over the ratchet sheave which is set so the sheave cannot turn in the direction the line is moving while it charges back onto the spool which impedes the line going back onto the spool which forces it back on the spool in a much more orderly fashion. When it is time to furl the sail the furling line is hauled on which causes the sail to be furler around the foil system. Because the sheave can only turn in the direction of the line as the furling line comes off of its spool it is assisting you hang onto the furling line at a ratio of 15:1. It is not reducing the load at all but the faceted sheave turns only in the direction it needs to to furl the sail, it makes the load on the furling line much easier to manage by hand. <O></O>
<O></O>
<O></O>
<O></O>
<O></O>
<O></O>
Jim Tech Service Group Leader<O></O>
<O></O>
Harken Inc.<O></O>

<O></O>



​
*From:* Shawn 
*Sent:* Friday, January 18, 2008 8:24 AM
*To:* [email protected]
*Subject:* Unit 2 Line<O></O>

<O></O>
Hello,<O></O>
<O></O>
I have recently&#8230;August that is, purchased and installed a new Unit 2 for my Tartan 37. I am very pleased with its performance, construction, and design&#8230;with the exception of the line that comes with it. It is crap, really bad! Why put such a line on a Harken product then charge $2000 + for it. I don't get it&#8230;.please explain. <O></O>
<O></O>
You can read on Sailnet here http://www.sailnet.com/forums/showthread.php?t=39946 how many others feel the same.<O></O>
<O></O>
Shawn


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## PalmettoSailor (Mar 7, 2006)

I'm considering the recently introduced Harken Cruising furler as a replacement of the Hood continous line furler that came on my Catalina 36.

From what I can gather, the "Cruising" unit is a no frills version, but offers the same design reliablity and ruggedness of the MkIV. The difference between the units seems to be the crusing version lacks features that racers would use like the removeable drum for full hoist sails and it comes with a single groove round extrusion vs. the aero shaped 2 groove extrusion of the Mk IV. The price difference is about $800. I can't see the above features adding that much value for our use, but if there are any signficant internal design differences it might be worth opting for the Mk IV.

Anyone know anything about this new offering from Harken?


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## TSOJOURNER (Dec 16, 1999)

One word of warning about the MKIV. The "tang" of metal connecting the head swivel to the halyard has shown a tendancy to fail. As in, mine did fail halfway through the Hook race. Harken responded immediately and sent a new (re-designed) swivel assembly at no charge. $43 to pay the yard to retrieve my halyard, along with the shackle and broken tab of extruded aluminum that formerly connected to the swivel car that came down rather unexpectedly with the sail. That, and two hours of personal labor and problem solved.

According to Jim at Harken, the Unit 1 and Unit 2 MKIVs have had the problem, apparently due to an underdesign in the interests of limited weight aloft. I bought mine in March 2008; no clue if/when all the units on the market have the older design versus the new one. I just installed the re-designed unit last Saturday, so far, so good.

While I was disappointed that the failure occured, I will say that Harken stood up immediately and took responsibility for the issue without even a hint of denying there was a problem. So yes, I'd buy the unit again, but I would find out which swivel car I was getting...


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## labatt (Jul 31, 2006)

Midlife - From what I was told, and having spoken to Harken about it, the "Cruising" furler is not anything like the Mk IV. It was designed to meet the price point of the production boat manufacturers that wanted to say they had Harken equipment on board. It is not built to the quality of the Mk IV and should not be compared to it.


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## T37Chef (Oct 9, 2006)

*Look twice*



labatt said:


> Midlife - From what I was told, and having spoken to Harken about it, the "Cruising" furler is not anything like the Mk IV. It was designed to meet the price point of the production boat manufacturers that wanted to say they had Harken equipment on board. It is not built to the quality of the Mk IV and should not be compared to it.


I agree 100%!

Look at them side by side, you'll see the differences. The cruising unit also only has one track instead of two in the MK IV.

I don't understand the logic in even producing a product like this under a brand name like Harken. It reminds me of John Deere producing the Home Depot'ed version of their lawn tractors...brings the whole brand down so they can earn a few more $$$ to satisfy their shareholders.


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## PalmettoSailor (Mar 7, 2006)

T37Chef said:


> I agree 100%!
> 
> Look at them side by side, you'll see the differences. The cruising unit also only has one track instead of two in the MK IV.
> 
> I don't understand the logic in even producing a product like this under a brand name like Harken. It reminds me of John Deere producing the Home Depot'ed version of their lawn tractors...brings the whole brand down so they can earn a few more $$$ to satisfy their shareholders.


Two tracks matters not a whit to me since I don't change sails often, or in race conditions where a few seconds or minutes extra time taken swapping sails makes a difference. I'm a bay crusier with a 17 year old crusing boat. All I want is a reliable furler, that allows reefing. I don't care about the racing features or the .02 of a knot the aero foil provides.

However hearing that the quality of the units are that different is troubling. The Harken crusing unit is less than the MK IV, but its not really "cheap". It is in the same price range as crusing offerings from other lines like Profurl. I spoke to my local sail loft and he says he's sold a few of these units and the owners are pleased. This guy is a member of the YC where I crew and supports the local racing fleet. He has a good reputation so I was inclined to follow his advice. I guess I'm going to have to contact Harken and do some more due diligence before making a decsion.


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## T37Chef (Oct 9, 2006)

Just offering some or the differences I could think of off the top of my head without looking at the stats for both, which I am sure your capable of doing yourself.

What are the quotes for the MKIV your getting? I ask because my marina is a Harken Dealer, and gets the best prices I could find anywhere up and down the bay. Maybe because I am a slip holder, maybe not, but if I remember correctly, I paid just over $2100.00 installed.


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## T37Chef (Oct 9, 2006)

The cruising units are fairly new and really have not had the opportunity to prove themselves one way or another. Hell, all furlers have had their problems I'm sure.

If there is one thing about Harken that I am confident of, is that they stand behind their product. If you have problems with it they will address it.


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## PalmettoSailor (Mar 7, 2006)

T37Chef said:


> Just offering some or the differences I could think of off the top of my head without looking at the stats for both, which I am sure your capable of doing yourself.
> 
> What are the quotes for the MKIV your getting? I ask because my marina is a Harken Dealer, and gets the best prices I could find anywhere up and down the bay. Maybe because I am a slip holder, maybe not, but if I remember correctly, I paid just over $2100.00 installed.


I need to do some more research. The Harken Cruising unit #2 or the Profurl Basic were quoted at $2600, $3365 for the Mk IV all prices installed.


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## Maine Sail (Jan 6, 2003)

*For me..*

For me the choice was very easy as I was able to see them side by side and all the Parts and pieces.

#1 The MK-IV has four more races of Torlon bearings that never need lubrication than does the Cruising.

#2 The MK-IV has unique independent upper & lower swivels. These swivels allow the head and tack to lag behind foil and allows the center of the sail to furl first for a much better reefed shape. With two extra rows of Torlon bearings in both the upper and lower drums that support this feature the sails furl easily even under load. That helps aid in a better sail shape when reefed and it WORKS! This is worth EVERY penny!!

#3 The adjustment factor is a BIG plus!

Is this stuff worth $397.00 more to you at MAP? I don't know but I gladly would have paid it and I did..

Pricing on a Unit 1, at MAP (minimum advertised price), shows a $397.00 difference between the MK-IV and the Cruising Furler. You DO NOT need a Unit 2 and a Unit 1 is more than enough for a C-36. I am running a Unit 1 on a 17,500+/- pound 36 footer with a 150 and it performs absolutely flawlessly and I've sailed her reefed in 40+ a fair number of times..

If you are being quoted an $800.00 difference your guy with the "good reputation" may not be treating you totally straight. Even the MAP difference between Unit 2's is only $615.00 not $800.00. There is ALWAYS more room than MAP pricing too. This is an EASY install and perhaps you may want to consider doing it your self to save some cake..

Using the "add to cart" option at PYacht, a reputable on-line retailer, the pricing is as follows;

MK-IV Unit 1 = $1359.89
Cruising Unit 1 = $1066.41

Difference = $293.48 (this is a far cry from $800.00)

MK-IV Unit 2 = $1965.60
Cruising Unit 2 = $1517.88

Difference = $447.72 (still a long way from $800.00)


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## T37Chef (Oct 9, 2006)

midlifesailor said:


> I need to do some more research. The Harken Cruising unit #2 or the Profurl Basic were quoted at $2600, $3365 for the Mk IV all prices installed.


Call Oak Harbor Marina, ask for Ken, get a quote for the MK IV Unit 1 or 2. While your at it, ask him the differences between the two and other brands...he will gladly offer his opinion.

Oak Harbor: <?XML:NAMESPACE PREFIX = SKYPE /><SKYPE:SPAN class=skype_tb_innerText id=skype_tb_innerText0>(410) 255-4070 </SKYPE:SPAN><SKYPE:SPAN class=skype_tb_imgR id=skype_tb_img_r0 style="BACKGROUND-IMAGE: url(C:\DOCUME~1\USER~1.YOU\LOCALS~1\Temp\__SkypeIEToolbar_Cache\e70d95847a8f5723cfca6b3fd9946506\static\active_r.compat.gif)"></SKYPE:SPAN>


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## J36ZT (May 18, 2008)

All I can say is the MKIV Unit 1 on a J/36 performed its trial run flawlessly, even with the crappy line supplied...no problems in both the furler and reefing modes. It was easy to install; took about two hours total to assemble onto the forestay even with reading the instructions step by step.

Amazingly, the best price I found for the MKIV was through Sailnet!

I don't know enough about the differences between the cruising models of furlers to make a judgement call. But, what I do know is Harken has a good reputation when it comes to furlers, and the MKIV has the features I felt would best suite my needs.

...but, that crappy line that it was supplied with HAS GOTTA' GO!

Skipper, J/36 "Zero Tolerance"


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## PalmettoSailor (Mar 7, 2006)

Thanks for the great input. I should add that I'm still waiting on a e-mail break down of the figures I gave and that we did discuss replacing the forestay as part of the install. Since he gave these as installed figures, my assumption is those prices include a new forestay.

Also, I appreciate the input on the Mk IV Unit 1 being adequate. There is a big difference in price there, and my boat is right on the dividing line per Harkens online guidelines.

Finally, Pyachts prices seem too good to be true. They are $300-$700 less than Defender (I got the real price not MAP) depending on the unit. ($410 less on the Mk IV #1) That big a difference hardly seems possible, but its apparently true.


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## T37Chef (Oct 9, 2006)

Depending on what you go with, you may want to consider what you may need in addition. I got two more 7403 and one additional 7401 lead blocks for my boat.


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## jrd22 (Nov 14, 2000)

Halekai- thanks for the info. on the MK IV. I just installed one on our Brewer 40 (unit 2) and altough I haven't had time to use it much, I'm very happy so far. I agree about the lousy line they supply with it, I can't get a good grip on it and have had to use the winch when reefing. Did you install the roller lead kit, we just ran the furling line through rings on the outboard side of the stanchions and I'm wondering if there is a significant reduction in friction with their lead kit? I was pretty sold on the Schaeffer, but my rigger convinced me that Harken was the way to go, and so far I am very satisfied. 

John


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## PalmettoSailor (Mar 7, 2006)

I wanted to thank Halekai and T37 for the input on the MKIV. It put me on the right track and after speaking to Harken, I know what furler I'll be installing; A Harken MKIV Unit 1. I'll need an extra foil and connector and the correct toggle, but other than that I should be good to go.

The jury is out on having my sailmaker install it, or going the DIY route. The quote is down to what I consider a semi-reasonable amount ($700) over the P-yacht materials cost and that includes a new headstay so I figure about $450-500 labor cost.


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## J36ZT (May 18, 2008)

Midlifesailor,

You may want to double-check the length of the forestay as compared to the overall length of the MKIV Unit 1. The "COMPU-SPEC" advised me to order an extra foil length and connector that I ended up not needing.

With the forestay off the boat, the MKIV can easily be assembled in an hour or two. I'm the kind of person who's reluctant to pay someone $75+ to follow an instruction manual, turn an allen wrench, and squirt some 5200 down some holes...so I did it myself. The only really technical part of the installation comes when/if you have to cut the final foil (hacksaw and file are not included in the kit). Really, it's that easy to get the MKIV onto the forestay. I didn't have to get/install the line kit, but can guess this might take an additional hour or two.

Fair winds/following seas,

Marshall
Skipper, J/36 "Zero Tolerance"


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## T37Chef (Oct 9, 2006)

J36ZT said:


> squirt some 5200 down some holes


I think you meant "Lock tite"


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## Maine Sail (Jan 6, 2003)

T37Chef said:


> I think you meant "Lock tite"


No, he did mean 5200. Harken supplies 5200 and a syringe to squirt in the screw holes and between the foils.

I used 4200 as 5200 is not even allowed on my boat..


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## J36ZT (May 18, 2008)

Yep, everything is included in the MKIV kit except a hacksaw, file, and a pair of plyers.

Otherwise, it comes complete with a tube of 3M-5200 (more than you'll need), a 20cc syringe, allen-wrenches, all the hardware and assorted pieces of the MKIV, and the installation guide. Oh, I forgot one other important item...about 75' of the cheapest crappiest line that has ever been invented.


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## 121Guy (May 6, 2007)

*Harken*

In my experience they are one of THE BEST companies in the marine industry.

Their customer support is only exceeded by their design excellence.

121 Guy


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## T37Chef (Oct 9, 2006)

My bad...The 5200 must be new, I still have the tube of locktite supplied with mine when purchased...summer 07


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## LifeWorthLivin (Aug 30, 2006)

*Don't believe the hype*

Replying to an old post here, but I would just like to respond to some statements that I find incorrect or misleading so this will be a little lengthy. Looking at a product on a web page or in a catalog and seeing it in person are very different things, and from reading as much information that I could find on the web about the Harken Cruising furler, I found that 95% of people who had an opinion had never seen one in person. In my search to choose the right furler, I read everything I could find and talked to 3 different technical people at Harken before finally taking their recommendation and ordering the Cruising Unit 2

First, let me back up and give the important info. This furler is going on a Passport 47 which is a big, heavy, cruising boat which I plan to take offshore, so my first requirement was robust construction. There has been some talk about pricing here, which is where the Cruising Unit 2 really makes sense for me. Then MKIV Unit 2 extrusion will only fit over 3/8" wire because it's designed to be lower profile, so I would have to step up to the MKIV unit 3 which is almost twice as much as the Cruising Unit 2 which will accept my 7/16" wire. So this was the first big sell for me, but I was very worried about construction given the difference in price. So, I called Harken 3 times to talk to different people who all said that they would spec the Cruising Unit 2 for my boat or a brand new Passport 470 for that matter. Their explanation was that the MKIV units are more expensive because of the extra engineering that goes into them to make them lighter and better for racing and that racers will just pay more for lighter stuff. Also, with my rigging wire size I got caught in a scenario where I would have to spend much more if I wanted the MKIV features. Here are the differences that they quoted:

*MKIV*
-Lighter extrusion sections to reduce weight aloft with 2 sail tracks, aerodynamically shaped to disturb flow less
-Furling drum is plastic in 2 halves so that it can be removed and the sail tracks can be used like a normal luff track for racing
-Upper swivel is lightened to reduce weight aloft
-Independently swiveling tack for better sail shape when reefed

*Cruising Unit*
-Stronger extrusion sections with single sail track, rounded for easier furling
-Heavier, stronger upper swivel
-Furling drum is Aluminum with a plastic top plate

So the main feature for me to consider was the independent tack swivel thing which was tempting, but not at the expense of durability, and not for twice the price. So, I decided to trust the folks at Harken and ordered it along with the quite pricey long link kit that raises the drum off the deck so that it isn't in the way of anchoring gear. Upon arrival, I can tell you that I was impressed. With most of the parts being matte black, it can look kind of plasticky in pictures, but that is all black anodized Aluminum. The extrusion pieces are beefy and very nicely machined. The toggle is a massive piece of cast stainless. Both swivel units are really nicely machined, black anodized Aluminum. It was installed last weekend and I am very pleased with the construction and operation of this unit.

In conclusion, I would just like to say that while the internet is a great resource and there are many good people out there with good information you obviously have to take much of it with a grain of salt. Especially with something like a furling unit where you can't typically just go down to the nearest marine store and "kick the tires" and very few people have actually seen things side by side, apples to apples. Calling Harken directly was really the clincher, and I had to get 3 of their employees to tell me the same thing before I would believe it. I hope that this helps anyone else looking for the same info. I think Harken makes good stuff and both are well made, they just have a different audience.

K Stewart


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## MarkSF (Feb 21, 2011)

I recently suffered a nasty halyard wrap at the top of my cruising furler. Not Harken's fault, the installing boatyard ignored Harken's installation instructions which clearly say you should have a halyard restrainer if the angle between halyard and forestay is less than some no. of degrees.

So when installing either Mk IV or Cruising look closely at the halyard and ask yourself if it might ever get caught up on the furler. The recommended halyard restrainer is only about $50 anyway and it sure beats bobbing up and down in the middle of SF bay wrapping the jib around the furler by hand. In worse weather it could have been VERY entertaining.

Also the furling line is much easier to get along with if you have Harken's recommended ratchet block. It makes unfurling the jib controllably and progressively much easier when the wind is strong.


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