How do adj. yolks work?

Yoniboi · Post by **Yoniboi** » Fri Dec 19, 2008 12:39 pm

NOT the basic principle obviously.

No, what i want to know is...

The excentric adjusters, how 'clever' are they? Do they change the angle of the triples as well as the offset from the stem, or do they just rely on everything flexing a little with the forks through them?

Have i explained myself????

Imagine the fork as stock. Everthing aligned. OK. Now I want to steepen the head angle so I 'offset' the top triple. Now the top triple and the bottom triple are not aligned. The front is a little more 'forward' than the bottom.
Are they still perfectly parallel? Or have both angled slightly so the forks aren't forced to go from the top to the bottom????

If you still don't understand, tell me and I'll write this again when I'm straight

Cheers
John

Post by **Hooligan** » Fri Dec 19, 2008 1:19 pm

john,

the eccentric inserts that are placed in the top and bottom clamps offset in a pair, keeping the forks parallel to the steering stem/headstock. the rake/trail is altered by moving the forks closer/farther from the original location.

Yoniboi · Post by **Yoniboi** » Fri Dec 19, 2008 1:21 pm

Then there are alternatives because I've definately heard of some that are used to alter the angle, not just the offset....

Thanks for getting back so quick
John

Post by **Hooligan** » Fri Dec 19, 2008 1:32 pm

hmm. i wonder how much you could really offset the angle without biding the whole assembly in the bearings/headstock/locknuts.

by moving the offset forward and back you are effectively altering the rake and trail.

Yoniboi · Post by **Yoniboi** » Fri Dec 19, 2008 2:07 pm

That's the point.

After riding the Spondon, the FZR is a supertanker that takes half the Indian Ocean to turn around in.
As my plan this winter is to change the fork on the FZR, and the new one will undoubtedly be shorter, I'll have to have a stepped top triple made up anyway so I figured that while I was at it, if I had it offset on purpose I could get the angle tightened without chopping and welding the frame (which I'm not going to bother doing)!

Of course the bottom triple will have to twist slightly to take the fork, but as I've heard of people straightening bent triples with nothing more than a scaffold pole and a little care..... I could go the other way and bend it a little, or not even bother, depending!

John

Sable · Post by **Sable** » Thu May 12, 2011 2:15 am

Yummy eggs

rgvlc · Post by **rgvlc** » Thu May 12, 2011 3:03 pm

The adjustables I had simply had an insert in the top and bottom yoke that could be rotated 180 degress giving different offsets. I dont think there are any that actually alter the rake angle of the forks, the only way I could see that working would be to have inserts in the headstock that would effectively seat the bearings at a different angle from the stock rake.

McFizzer · Post by **McFizzer** » Fri May 13, 2011 1:58 pm

When I talked to Steve and read up on here on the PJ he had just machined the top nut and had a bushing made that pushed the top triple foward a mill or 2 and it brought the rake down to like 24.5 degrees or somewhere abouts that.

My question on this is, on the RU forks, you can't pull them up, can you machine the top triple to allow the fork leg through? or would you have to throw the actual leg on a lathe as it's got a step in it for the handlebars to rest on.

I'd also like a pair of adjustable triple but for the price....mehhhh I'm looking into picking up a set of 07+ R1 forks to bang on..