Brake Question

[Carl Walichnowski]

So I purchased a top hat in order for the back disc brakes to fit/work. Now the issue is the caliber now hits where the chain is so that’s not working. Has anyone experienced the same issue & if so how did ya fix it? I was thinking a bigger disc would allow me to raise the caliber and that’d make it fit? Anyone try this? Any help is appreciated.

 

[gary55]

Yah you gotta get a disc large enough and sprocket small enough so the sprocket don't interfere with the caliper. Your on the right track. I use a jack shaft setup so I don't have this prob. with my rear disc. I'm sure someone will chime in soon who has tackled this prob. and can shed some light on specific sizes that work.

 

[dparenti13]

I literally just ordered 203mm rotors and a top hat adapter yesterday. You need a rotor large enough in diameter for the caliper to not hit the top of the chain on the sprocket. The spacing between the rotor and sprocket just needs to be wide enough for the chain to not hit.

 

[JerboaJohn]

just chime in that mbrebel has various disc spacers if you need side clearance.
this was a big reason I didn't do rear disc on my roadbike bcs a 40T isn't small enough than 203mm disc to clear. 38 might just clear the caliper but I couldn't go smaller n lose my low end.
I avoided the issue with my cruiser bcs the ghettobike hub mounts the disc on the freewheel side

 

[dparenti13]

I run a 36T and I'm pretty sure that a 203 will clear it by a good amount, I'll let you know when I get the adapter in.

 

[Spare_Parts]

I have a MB Rebel adapter with a 203mm rotor and 36t sprock. The caliper clears but it's close. You either have to remove the caliper or the master link to get the chain off. That is with a 410 bicycle chain.

Each adapter is a different offset so one may work and another won't.

 

[Spare_Parts]

Rear rotor clearance

• Spare_Parts
• Jun 16, 2018
• 1

With the MB Rebel sprocket adapter I ended up with only 1.5mm clearance!

 

[Old Busted Hotness]

I put my caliper in the rear triangle away from the chain. It's tight, but it fits.

Welding required.

 

[Spare_Parts]

I did the same on the new bike.

Rear caliper mount

• Spare_Parts
• Dec 16, 2018

 

[Old Busted Hotness]

Also, that hole in the sprocket is for adjusting the brake pads.