Best calipers and rotors for FZR600 fork swap

[Nobade]

Hi all, new guy here but not to bikes. Got myself a '75 XS650 I am in the process of restoring, and have replaced the extra long chopper forks it came with with a set of FZR600 forks. I have been trying the search function to find threads about this, but no definite answers yet. The question is, what is the consensus on the best calipers and rotors to use with a spoked wheel? I have a decent machine shop and can make quite a bit to make things work, but of course the closer to bolt on the better. Wanting to use dual front discs. What I can't tell is are there any calipers available that will bolt up to the fork's bosses and not hit the front wheel? Or is everything going to have to be custom? Thanks!

 

[gggGary]

I think the fizzer parts (blue dot calipers) will all bolt and play if you use rotor to wheel spacers. Not sure of the thickness needed. Motolanna makes a 10mm rotor spacer with the rotor centering collar. Others do not have the collars on their spacers.
search fzr forks for some threads. I saw 13mm mentioned for the spacers. back of caliper to spoke clearance can be a gotcha.

 

[Nobade]

Thanks for the reply, I got the triple trees installed/mocked up today so time to do some careful measuring and start cutting metal. I am looking forward to seeing this thing live again!

 

[gggGary]

Would love to see what you come up with, please do post with pics and dimensions!

 

[Nobade]

I am very curious to see what I end up with also. Will certainly post pics once it's up and working!

I did get the All Balls conversion bearing kit in, and it works well with no machining needed. Using a Seca II top clamp to get a handlebar mount. Time to rebuild the forks tomorrow, then figure out what I will have to make as far as bearing spacers for the smaller axle and fit the narrower wheel into the wider forks.

 

[Scotchmist]

I've trying to do the same conversion at the moment. Instead of the ubiquitous 'blue spot' calipers I'm running the original FZR600 calipers as they suit the bike a better. Using a spoked XS650 wheel with custom spacers the back of the FZR caliper hits the spokes. You'd probably need an extra 5mm of clearance which I'm not sure is possible. My solution is to use a larger disk (320mm) than the FZR used from a Ducati and make a custom caliper mount that moves the caliper a little further up the fork leg. Combined with a 17mm disk spacer there seems to be plenty of clearance (c.5mm) between the rear of the caliper and the spokes. Still at the mockup stage at the moment. Here's my thread...
http://www.xs650.com/forum/showthread.php?t=41880

 

[Airwolfie]

I got the USD's on my bike. Blue dot is tight on the spokes, but I shimmed about 1mm off the fit surface on the caliper's mounts, and beveled the back a bit where the spokes hit and it's fine now, very close but works well. Done about 200 miles already and no hiccups so far.

The spacers for the discs vary between 11- 15mm, you have to measure yours to suit. I used some nice aftermarket discs for the Yamaha FZR or Genesis. You will also have to get bearings to suit the bigger axle, they are about, but you got to look. The place I got mine off does not do them anymore. Don't forget the dust seals!

 

[Scotchmist]

I finished my FZR swap a few weeks ago. Definitely not the most handsome of installations but I've got loads of room (c.4mm) clearance between the caliper and spokes and used the larger 320mm disk off a Ducati.

Pictures here...

http://xs650.freeforums.net/thread/16/xs650?page=3

 

[gggGary]

Sharp work there Scotchmist.

 

[retiredgentleman]

Scotchmist:

Well done indeed! Real nice machining. I'm a big fan of having up-graded brakes.