Hobie Cat Forums

Hi,
has anybody experience with changing the rotation arm position? On the older Tigers it was mounted above the boom. As far as I know from the 2009 version onwards the arm was mounted directly at the lowest point of the mast (together with the lower cunningham block).
Is it possible to do change that on a 2007 Tiger, which additional parts do I need on the mast? Is it the same arm?

Stef

Hi Stef,

It's an easy change and I'm in the process of doing it right now on my 2007 Tiger. You just need a longer bolt at the bottom of the mast, two 16mm micro blocks, and two micro cam cleats. Find the latest instruction set (2012 version) and it shows you the whole setup.

Mark

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1989 Hobie 18 Magnum "Rhapsody"
2007 Hobie Tiger

And you'll need to install a reinforced grommet in the front portion (center) of the tramp and some cleats on the hulls to control the system same was they are on the Wild cat - just have a look at an owner's manual for tips on rigging.

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Jacques Bernier
http://www.hobiecat.com/
http://www.facebook.com/HobieCatCompany

HI!!! i have a 2008 tiger, but with a nacra mast, and i put the rotation arm in the base mast. It works very well. If u need pics, let me know

Gonzalo Argentina

Thanks to all your answers!

@Mark and Jaques:
can the original bolt that helds the rotation arm be used or do I need a different on?

Please post photo as I may relocate my rotation arm.
I always felt that it's original location above the boom worked poorly.
Years ago, I relocated the pass through hole on my 21SE with the intention of moving it and did not finish.
I drill a new hole, installed a new compression sleeve in mast and installed the new cover plates and picked up a new stainless bolt. But stopped before removing the arm as it is connected to the diamond wires.
Any info would be appreciate.
Simplicity and functional is where I want to end up.

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Bill 404 21SE

Hi Stef,

No, you can't use the original bolt for the mast rotator. The diameter of that bolt is larger than the one used at the mast base. You have to get a new bolt for the base that is longer than the original so that it accommodates the width of the rotator arms on both sides.

Mark

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1989 Hobie 18 Magnum "Rhapsody"
2007 Hobie Tiger

Here are some pics of the lowered rotation bar from our club boat. Can't take credit for the conversion - it was already done when we received it.







You can find the higher res versions here: http://imgbox.com/g/wZYLvtd5Fm

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Jeff R
'88 H18 "Jolly Mon"
Sail Michigan's Great Lakes in 2013
cramsailing.com

Thanks for the photos, but my real question is how is the rotation arm in rigged and how does one operate this setup and when?
Thanks.......

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Bill 404 21SE

Hi Bill,

You can see how it's rigged in the latest version of the Assembly Manual here:

http://www.hobiecat.com/support/pdfs/tigerassy.pdf

Mark

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1989 Hobie 18 Magnum "Rhapsody"
2007 Hobie Tiger

Not sure if this is the proper way, but I can at least relay what we've got and confirm that it works.

As mentioned in previous posts, the arm is mounted to the lower cunningham blocks. There are spacers on either side to accommodate the reduced width. Sounds like a smaller diameter bolt would be required. I've had good luck finding parts like this at Fastenal.

Vertical height of the arm is controlled by a line that runs up to the gooseneck. You want the arm below horizontal and fairly close to the tramp but not touching.

We added a reinforced grommet to the tramp just aft of the tramp pouch. Line is led from the cleat on one side, under the tramp, up through the grommet, through the block on the end of the rotation arm, back down through the grommet, and over to the cleat on the other side.

This works OK. This setup seems to place a lot of pressure on the tramp although our grommet reinforcement is quite robust and no evidence of tearing. Also, the line seems to always get unbalanced. Too much on one side, not enough on the other. There is probably a better way but I haven't researched it well enough to make any changes. One thought I've had is to attach a couple of small blocks to spectra lines under the tramp (terminated at the hulls some place) so they can take the force of the 90° turn up through the grommet.

Finally, as for when to use it, the general rule of thumb I've heard is this: Upwind, arm should be pointing at the side stay. Can start to rotate toward the rear crossbar as the wind comes up to depower - perhaps slightly forward in very light air. Downwind it is released so the arm points as far forward as possible.

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Jeff R
'88 H18 "Jolly Mon"
Sail Michigan's Great Lakes in 2013
cramsailing.com

The system you guys are describing is the same system that's stock on the H20. In my experience with the 20, this is a less desirable system than one that's controlled from the boom (I actually modified my 20 away from this system). There are some issues with the tramp mounted systems-

As described above, the lines have a tendency to get pulled all to one side if you're not careful. When that happens, the only way to increase rotation is to climb to the side with all the line and release the cleat. This isn't always feasible in high wind if the side with the line happens to be the leeward side.

Also, with the cleats located on the deck/hull, the rotation control is easy to adjust while on the trapeze, however, it is quite difficult to adjust while sitting on the hull due to the awkward angle of the line. We also found that we rarely adjusted the rotation while on the trap. It is typically a set-and-forget adjustment depending on point of sail.

Last, with the rotator control running off the boom, the rotation automatically changes with changes of trim angle. When it's run from the tramp, the mast rotation is fixed relative to the boat and doesn't self-adjust. In other words, with a boom mounted system, you travel out and the angle of mast rotation relative to the sail stays constant so you don't need to make any adjustments. With a tramp system, you travel out and the mast stays fixed meaning you are now under-rotated and have to re-adjust.

Just some things to consider.

sm

Agree with SM. I prefer my H18 setup.

There may be an advantage to the lowered arm, but I haven't figured it out yet.

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Jeff R
'88 H18 "Jolly Mon"
Sail Michigan's Great Lakes in 2013
cramsailing.com

A few comments that I don't see in previous posts, based on my having moved the mast rotation arm to the base of the mast on my 2006 Tiger:
1. I purchased a new rotation arm/wishbone with smaller holes to exactly fit the smaller bolt at the mast base, and narrower to exactly (with a little bending) to exactly fit the width at the base of the mast. I think I bought it from Murray's.

2. I much prefer the rotation arm at the base of the mast for the following reasons in addition to those stated:

a. I considered the arm sticking out and sometimes moving rapidly from side to side to be somewhat of a safety hazard.

b. This allows attaching a hand-held marine-band radio to the boom.

3. I attached the cleats for the rotation control using the threaded holes that were originally used for the deck strap for the original spinnaker block attachment points. This required using medium-sized cam cleats where I would really have preferred micro-size, but with the Harken cleats with top cover, they have worked out okay.

4. I installed the rope that goes diagonally from the end of the arm up to the boom gooseneck through a piece of 1/2 inch (I think) pipe. I saw this on another Tiger; it doesn't make much difference, but does provide a smooth surface for the spinnaker sheet to slide across, and is easier on the foot when applying positive mast rotation with my foot.

Russ S., Hobie Tiger 1696

The main reason that I see for having the mast rotation adjustable from the hull is for racing purposes only. Where upon rounding the weather mark the crew has their hands full with easing jib, raising daggers, easing cunningham and raising the chute. While the skipper is driving and easing main sheet and traveler they can ease the mast rotation also (easy to reach).
This allows the team to change gears quicker at the top corner.
Everyone will pretty much have to figure out on your own what works best for yourself.
I like mine on the deck since I used to sail a 20 and will be changing to a 2:1 purchase because I sail in 15+ almost every time out (similar to the WildCat).