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Lukens
06-14-2015, 09:03 AM
Trying to install new pin in my clutch fork. Without a BFH, I see no way that it will project through the shaft. The pin's tapered, the bore's tapered, and I've removed any burr that might be interfering. What am I missing?

Russ

37800

M_Pied_Lourd
06-14-2015, 09:17 AM
Hi Russ,

The pin doesn't protrude all the way through the shaft I believe.

I took some video of mine when I was doing my 59 a few months ago if it will help.

It is towards the end of the video...

https://youtu.be/9H4LI35oTK8

Cheers
Tush

Marvin Gruber
06-14-2015, 10:30 AM
Do a dry run, put the fork on shaft and install pin. Bet it will pull itself into the fork woth several threads,

Marv

Lukens
06-14-2015, 10:31 AM
Chef,
Watched your video - I always enjoy them. Something is amiss here. My pin is a Moss part no. 596-055. Their description is "heavy duty"... not sure if that has any bearing on the problem. Regardless, I'm 100% positive this pin will not fit the current geometry. I can't get the first thread started in the fork. I'm not yet ready to press (beat)?) the pin in until the threads grab. Furthermore, I've seen numerous diagrams showing the pin going through the shaft and into the backside of the fork.
Stumped,
Russ
37802

Lukens
06-14-2015, 10:36 AM
Marv,
I've tried the dry run. I've got the shaft on my bench so that I can cross drill for a 1/4" bolt. I'm pretty certain that if I can get a thread started, I'll strip it right out of the fork. Thinking maybe I'll chuck the pin in a 4-jaw chuck and polish the diameter.

Lukens
06-14-2015, 11:07 AM
Bingo!
When I put the pin in the fork (without the shaft) it fit well. I decided not to polish down the pin. Instead I found the taper on a rat tail file to be "close" to that of the pin. By holding the file in a vise and rotating the shaft by hand, I was able to get a good snug fit. Now the assembly looks to be right. If it's not perfect and I don't think they ever were, I've got the added assurance of the new cross bolt.
Thanks for all the quick responses. Obviously you guys like me, hold your church in your garage.
37803 37804 37805

titanic
06-14-2015, 11:51 AM
Lukens-You might find this article interesting about the fork pin. The small end doesn't even fit the hole in the "far"side of the fork. https://www.buckeyetriumphs.org/technical/clutch/ClutchShaft/ClutchShaft.htm
Berry

Lukens
06-14-2015, 01:03 PM
No offense Barry but that article clearly shows that the pin does protrude into the far side.
Reread your post. Yes, the pin doesn't come close to "fitting" the hole, but it does protrude into the hole. I can only assume Triumph drilled to that depth to allow for inconsistencies in the taper fit.

Geo Hahn
06-14-2015, 01:14 PM
I think he means that it protrudes but is not a fit (no contact).

titanic
06-14-2015, 04:31 PM
Right (thanks Geo.). It just dawned on me that the pic. in the posting by Luken is from the Buckeye article. I think Nelson made a bushing to fit the smaller end of the pin.
I march to the beat of a different drummer and made a straight pin the dia. of the hole in the far side of the fork. The dia. was about .323"(I think) and the hole in the near side of the fork was enlarged to match. I used 4142 steel (not heat treated) and it has been in place for at least 15 years, without a problem.
But next time the trans. is out, I will do the aux. 1/4" bolt trick.
Berry