"Grimeca front disk brake conversion for Rally 200 with SIP PK Fork"

"Grimeca front disk brake conversion for Rally 200 with SIP PK Fork"


          

I recently bought a pk fork conversion from SIP along with the new Grimeca classic 20mm disk brake, bitubo front PK shock & full hydraulic kit with master cylinder at lever. I started off by test fitting everything and found that there are a few fit issues. The first I have already remedied--and that is the shock base mounting holes are at a different distance on the pk than they are on the PX (for the which the kit is designed for)--but I gave the hub to a machinist friend of mine and he machined the top hole on the hub to match the shock. Now that I have mounted the shock base, I have run into two more fit problems--#1 the top shock mount is 8 - 10 mm in too much (Refer to photo--Notice that the top of the shock is not centered in the mount hole)

As far as the top of the shock goes, I know that I can force it in, but it will not seat in the center of the top mount and I am assuming that it will not go up and down properly due to the enormous tension. I could move the top mount outward, but then I think I will interfere with how the fender will mount. Has anyone come across these same problems. If so--I would greatly appreciate the help.and

My #2 fit problem is that the bitubo's second tube blocks one of the mount bolts for the caliper (Refer to photo).

 I have filed down the head of a button head screw but have not quite cleared it, and it looks like I will either have to file the inside base of the shock or file the hub screw mount--I am reluctant to do either. As far as the top of the shock goes, I know that I can force it in, but it will not seat in the center of the top mount and I am assuming that it will not go up and down properly due to the enormous tension. I could move the top mount outward, but then I think I will interfere with how the fender will mount. Has anyone come across these same problems. If so--I would greatly appreciate the help.

This is a bit late, but the caliper mounting screw that was behind the bitubo, I had a machine shop machine the screw hole to accept a flat head countersunk screw.  Problem solved. 

Regarding the top of the shock not centering in the mount--I elongated the bottom screw mounting holes on the Bitubo shock, so that the top of the shock could be tilted into place.

I have been running this setup now for 3 years and am very pleased with it.  It actually stops when you want it to and it does not dive when you hit the brakes hard.

How did you get on in the end, did you get it sorted?

I'm thinking of getting my Rally 200 converted but dont know where to start?

cheers, Chris

Thats gonna be amazing once you get your fitting sorted. Looks really clean!

I'll be installing the classic Rally fork/disc combo next week. I hope it works out with the new heavy duty spring up front. I wish Bitubo would make a dampener for the old rally suspension.