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[Twolanerider]

Several weeks back had reason to have the tranny case out of the red bike (the 05).  So the primary was completely off.  Saw something worth sharing for anyone else who took part in the GP Designs bearing support group buy quite a few of us did a few years ago.

When the GP bearing support had been in the bike about 20k miles I had it down for a loose comp nut.  The original .020 shim between the extension shaft and the rotor was beat down to about .010".  The GP designs kit also adds another .020 shim farther outboard.  It was damaged also though not as much.  Averaging about .014 but still retaining most of its shape.

The comp nut had been loose only a very short time.  So doubted it caused much of what was seen then.  But couldn't discount the shared events. 

This time, however, it's about 22k miles later.  Comp has never again been a problem.  Everything was replaced to spec when last apart.  And comp was of course still tight.  Something obviously not quite as it should be though.

Pictured is the inner shim between the extension shaft and rotor.  It's .003-.006 and of course badly deformed.  Can't beat it down that much and retain shape.  The outer shim added by the GP kit was again .010-.012". 

All the remaining compensator parts were within spec and otherwise ok.  Something loose enough to let it beat though.  Never felt a vibration nor heard anything.  But it's obviously not right.  This time had run long enough that teeth in the center of the rotor had started to wear leaving it loose on the crank.  Crank is fine but replaced the rotor.

When it went back together this time I put all the original compensator parts back in.  I recognize the output of this engine makes the idea of what the GP Designs bearing support offers a good idea.  But something isn't working in Bristol Fashion in the compensator or it wouldn't beat these shims.  So it's back to a full compensator, no more external bearing support and keeping the finger crossed it never eats itself for lack of a Timken left side bearing.

[hogasm]

Don I have seen this on bikes without the G P Design support.

comp nut not tight.

[hd-dude]

Don I have seen this on bikes without the G P Design support.

comp nut not tight.

Yep.

[Twolanerider]

Have seen it before with loose comp nuts also.  This time, or at least the second time, it's a circumstance where I'm sure it was tight though.  

First time saw this in this bike was when it was taken down because I'd heard/felt the comp nut loose.  Hadn't been run that way long.  Not long enough to make it look like the shim had been victimized by a planishing hammer on PCP anyway.  But I don't dare discount the coincidence as I know it had gotten loose during that cycle.

This time it never had though.  And was tight when I disassembled it to fix the tranny.  So even with a tight comp nut it had done what's pictured in a little over 20k miles.

No way to get feeler gauge or other shim stock inside the assembly to see if there's gap that shouldn't be when assembled.  Also not going to worry about it.  Went back together with the stock comp parts and called it good (enough for now).

In another 25k or so it'll likely be time to change the primary adjuster shoe.  When open the primary for that will inspect it again then.  Just posted the incident for anyone with the same parts.  If they've got the outer cover off sometime might choose to go just a bit deeper and do a prophylactic look.

[hd-dude]

Not doubting the nut was tight but interesting that it got beat up so bad. Must be something wrong with the stack that allowed a slight bit of movement to destroy the shim and rotor.

Do you notice if things are smoother with the comp assembly back in?

[Twolanerider]

Do you notice if things are smoother with the comp assembly back in?

Jim, would like to say for sure I noticed some difference before and after but honestly can not.  Was busy while messing the tranny repair and got it done on the occasional hour or so of an evening over a couple weeks or more.  So enough time in between I can't say my butt really knew for sure.

The GP part went in while the engine work was done a few years ago.  So too many changes at that time to say any one thing felt different.  I was fortunate in that I never picked up any of the vibration that MJ and a couple others picked up when you honcho'd that BP group.  So I didn't have any bad "feel" to lose by putting the compensator back in.

What I think I've noticed are a couple of small things.  It feels less "abrupt" at hard take off from a stop.  I also think neutral is a bit easier to find.  Not while stopped but when decelerating like coming up to a toll booth.  Not sure of either. Those are just the impressions I think I've noticed.

Hopefully by next fall or winter will be ready for the primary shoe so will have an excuse to check the stack again.  In the mean time won't worry about it unless it gives me reason to.  The damaged rotor was a good reason to install a 45 amp rotor that I'd had stuck in a drawer for a long time looking for a home.

[hd-dude]

Thanks for the feedback was just curious. I still have mine in and several of the locals here do as well. Only one had the vibration problem locally that ended up removing the support. I still have one of these units on the shelf to find a home for......

[Twolanerider]

Thanks for the feedback was just curious. I still have mine in and several of the locals here do as well. Only one had the vibration problem locally that ended up removing the support. I still have one of these units on the shelf to find a home for......

I'd like to keep it in mine too Jim.  Really like the bearing support way out on the end of the shaft like that.  But after what is likely a repetitive issue here decided to go without.  Don't want to eat a rotor every 18 months. 

Can't say it won't go back in sometime.  But want to see a mileage cycle without it first to at least isolate things.

[Twolanerider]

 As an unexpected aside to conclude this thread have to unfortunately comment on the company.   Have over many weeks now left several email and voicemail messages all saying I'd like to be a customer and buy a part.   Want to get a couple of the shims.  

No response from the company.   At all.  Too bad.....