PDA

View Full Version : Rear disc caliber location

alancw3
11-30-2018, 08:51 AM
i was looking at a used disc gravel bike that had the rear caliber located/mounted on the nondriver side rear seat stay. looking at other bikes the rear caliber is located in the rear triangle (possibly called flat mount). probably more appeasing esthetically but my question is from a performance standpoint. does the triangle location provide better stopping? thanks all for any input.
tigoat
11-30-2018, 09:09 AM
Yes and no. If a moment is produced by the rear brake caliper mounted on either place, then I would say the chainstay would flex less (stronger) than the seatstay. This could be quantified on paper but on the road you will likely not able to feel the difference. The rear brake caliper looks nicer nested (like flat-mount) in between the rear stays.
David Tollefson
11-30-2018, 09:10 AM
I've built both. No performance difference to my discernment, though the seatstay location usually requires a gusset tube between the seatstay and the chainstay at the upper mounting bolt. I prefer the seatstay location, though.

This is not dependent on mount type. Chainstay mount is not, by necessity, flat mount.
oldpotatoe
11-30-2018, 09:58 AM
One consideration is if you want a rack or rear fender.. Chainstay mount makes it a lot easier altho there are racks and fender struts made to go outside seat stay mounted caliper.
alancw3
11-30-2018, 10:47 AM
Yes and no. If a moment is produced by the rear brake caliper mounted on either place, then I would say the chainstay would flex less (stronger) than the seatstay. This could be quantified on paper but on the road you will likely not able to feel the difference. The rear brake caliper looks nicer nested (like flat-mount) in between the rear stays.

thanks for your input; exactly want i was looking for.
d_douglas
11-30-2018, 12:37 PM
My everyday commuter is a 15yr old titanium Redline that has an old school ISO mount on the seatstay. Never had a problem and the bike has been used a lot. I put a rack on this year for the first time ever and I need to find the 'right' rack to make it around the caliper itself - that has been the only drawback.