Low friction fork bushes

jseng1 said:

I'm not seeing wear on the stanchions when using non metallic bushings.

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I have seen wear, on the disc side the chrome disappeared on the front of the stanchion from the twist and dive action of braking. There was only one distributor of Turcite in the UK and they had premium pricing and now seem to have vanished.

I applaud your idea and ability, nice job! Making the bushings must be very satisfying and yield a great sense of accomplishment. It would be easy to say that the material cost and the application of your talent doesn't add up to a very good value proposition, but the intrinsics are priceless and as pleasurable, in many respects, as dawning a helmet and leaving nagging issues behind. Do read "Shop Class as Soul Craft".

For those of you, myself included, that don't have the resources or ability to do such fine work I recommend that you look hard at the NYC Norton low friction bushing kit; my fork assembly moves in and out with the aplomb of a slide trombone.

Yes its mean on the wallet. There may be wear but I haven't seen it myself. My stanchions show chrome wear from the bronze bushes so I turned the stanchions 90 degrees and so far no visible wear since 2009.


Note:
"Turcite-B is a different animal. Its coefficient of friction is about 1/3-1/4 that of Delrin AF. "
Hence the low wear.

I turned the prototype bushes on my manual lathe (now made by CNC) and the fine machine marks are still visible after 50,000 miles.

I have a set of Jim's turcite bushings in my bike right now, no complaints at all, but some stiction that was reconciled by switching out the never leak seals with stock and running lighter fork oil

acadian said:

I have a set of Jim's turcite bushings in my bike right now, no complaints at all, but some stiction that was reconciled by switching out the never leak seals with stock and running lighter fork oil

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+1 0n switching from the always leaking Ariete to the Leakproof high stiction seals, and then back to stock.

I had to fettle the Turcite bushes a bit with some wet dry wrapped on an old fork tube so they didn't bind with my new.tubes.

After all that...joy.

Unfortunately all Norton fork tubes are not the same diameter. Stock stanchions range from 1.356” to 1.359” but some aftermarket tubes are out of spec and can measure too large and cause binding at 1.360+" . Note that Esmerela custom fit the bushes to her particular stanchions.

Longer bushes or alum spacers for avoiding top work beautifully but only if you plug the 1/8" holes at the bottom of the stanchions (most people miss that). Alum spacers should be fixed (slit and expanded) so they stay at the top of the fork leg and won't slide downward.

Esmerela is on the right track when tightening up the clearance of the damper cup and top collar to improve rebound damping and I applaud her for the fine machine work in making bushes etc. The photos below show how you can modify the stock damper parts to get the damping results that Esmerela achieved. For those who don't have machine tools you can DIY - These inexpensive damper mods along with the slippery synthetic bushes transform the performance of Norton forks.

Drill and sleeve the top collar with 3/8" ID KS hobby shop brass tubing (use red loctite).



Use a cone (carpenter plumb bob shown with socket underneath) and tap carefully with a hammer to swell the open end to .680″

RoadScholar said:

I applaud your idea and ability, nice job! Making the bushings must be very satisfying and yield a great sense of accomplishment. It would be easy to say that the material cost and the application of your talent doesn't add up to a very good value proposition, but the intrinsics are priceless and as pleasurable, in many respects, as dawning a helmet and leaving nagging issues behind. Do read "Shop Class as Soul Craft".

For those of you, myself included, that don't have the resources or ability to do such fine work I recommend that you look hard at the NYC Norton low friction bushing kit; my fork assembly moves in and out with the aplomb of a slide trombone.

Click to expand...

I was wondering if anybody had tried the NYC / Cosentino kit, thanks for the feedback RoadScholar.

Cheers,
cliffa.

gortnipper said:

+1 0n switching from the always leaking Ariete to the Leakproof high stiction seals, and then back to stock.

I had to fettle the Turcite bushes a bit with some wet dry wrapped on an old fork tube so they didn't bind with my new.tubes.

After all that...joy.

Click to expand...

I thought the Ariete seals were supposed to be the dogs danglies?

I did the mods of the front fork as specified on JSEng's website, except for the Turcite bushings (could not get this material locally, and was unaware of the Delrin alternative) and fitted the longer bronze fork bushings, and found a remarkable improvement in front fork action. so recommened imo.

All
Thanks for your kind comments.

I have allways used standard seals in the Commando, oddly enough the Ariete seals work fine in my t160

cliffa said:

I thought the Ariete seals were supposed to be the dogs danglies?

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So did I. They leaked like a sieve.

gortnipper said:

So did I. They leaked like a sieve.

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Counterfeit?
I found Ariete seals better than std.
Even riding over rough, unpaved roads, they never leaked.

Maybe. IIRC, they came from ebay but had the lubrication sachet.

I suspect most of the Ariete seals on ebay are counterfeit not unlike NGK plugs.

cliffa said:

I was wondering if anybody had tried the NYC / Cosentino kit, thanks for the feedback RoadScholar.

Cheers,
cliffa.

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I just installed a set on my 850 MKII. I'll report back when the bike is on the road again.

acadian said:

I have a set of Jim's turcite bushings in my bike right now, no complaints at all, but some stiction that was reconciled by switching out the never leak seals with stock and running lighter fork oil

Click to expand...

I tried the leakproof seals many years ago. The sticktion was bad enough that I had to rebuild the forks all over again and replace the leakproof seals with stock seals. It the case of leak proof fork seals - the cure is worse than the disease.

jseng1 said:

I tried the leakproof seals many years ago. The sticktion was bad enough that I had to rebuild the forks all over again and replace the leakproof seals with stock seals. It the case of leak proof fork seals - the cure is worse than the disease.

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Thats what I’ve been told before by people who I tend to listen too.

But I’ve never tried them myself.

Add me to the list of folks who tried Leakproof seals in the past on Commandos and found them to have way too much friction.

Ken

Leakproof seals ? are'nt all seals intended to prevent leakage ? Never heard anyone ask "can I have a pair of leaking seals please "
Just wondering.

I use the Ariete seals on both of my bikes and they dont leak.
I have JSM Turcite bushes in the race bike, had stiction for awhile and some chatter in corners where the throttle position was neutral, only to find the stanchions were out of parallel slightly(side view) .
Had a crash that created the need to replace the fork stanchions , sorted the parallel problem again and the forks work a treat.
Both bikes run the Lansdowne needles so can run lighweight oil as well.
Regards Mike