1999 Rock Shox SID XC compatibility with modern disc brakes?

豐JEDIMINDTRICKS

Dirt Disciple
Noob here and thinking of buying some 1999 Rock Shox SID XC forks to go on the Rock Lobster Team Tig SL frame I've just bought. Just wanting to know if the disc mounts are compatible with more modern disc brakes or would I need to be looking at older disc brakes? Any advice would be much appreciated
 

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So, I'm reading that modern disc brakes aren't compatible with these older forks without adapters as these forks will have an old international standard mount. So now my question is what is the newest series of Shimano LX/XT or XTR disc brakes that will support these forks without serious hassle?
 
I have no idea. Complete noob here. Just was what I read from Google AI, which says using adapters can cause serious problems too, but from my experience of Google AI, it appears to talk complete nonsense most of the time
 
You should find easily IS to PM adapters. If you are using 160mm, you'll fid easily a 160mm IS-to PM front. BUt check that it is a front one, for rear one I think they are slightly different. All barkes came with IS in the late 90's early 00', but around 2010 everybody changed to PM due to easier centering capabilkities. BWith IS you need a set of shims for adjusting the caliper laterally.
 
You should find easily IS to PM adapters. If you are using 160mm, you'll fid easily a 160mm IS-to PM front. BUt check that it is a front one, for rear one I think they are slightly different. All barkes came with IS in the late 90's early 00', but around 2010 everybody changed to PM due to easier centering capabilkities. BWith IS you need a set of shims for adjusting the caliper laterally.
Now I'm confused. So they are IS mounts on the forks I posted? Thanks for the reply btw
 
They are an IS mount. 51mm between centres.
other standards existed at the time including formula which was a smaller distance between centres and post mount where the holes are turned and threaded.
SID didn't come with formula mounts, not many forks did and not in 99.

you need the adapter posted above, but depending which brakes you buy, they may come with adapters already.
 
I have a few SIDs of that era with modern discs on them. Lots of adapters available to fit whatever configuration of caliper mount you have and whatever rotor size you want.
 

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