Boxerworks.com

I’m the proud new owner of a 1978 R100/7. I actually don’t know which variant it is…it has had a mediocre cafe racer build at some point in its life. Almost nothing on the bike works, so I have a lot cut out for me, though it does run and shift gears!

I’m trying to decide if I want to stick with the single, ATE brake or upgrade to dual discs in the front. I just bought a pair of Brembo lower fork sleeves from a dual disc R100. Will these fork sleeves fit on the stock tubes from the 1978 single ATE brake front end?

If I can get these to work, I’ll upgrade brakes and switch to spoked wheels (it currently has Lesters). If not, I’m just going to rebuild/refurbish what’s on there.

Thanks, excited to be part of the club!

Delaplanet
Oakland, CA
USA

Welcome to the forum! What year are the sliders from? Tubes changed diameters at some point. The usual way to go is to add a second fork slider to accept a second ATE caliper...you'd have to find one from an RT or RS or something like that from that period. You'd also have to look into brake lines and maybe a new master cylinder. I can never figure out what diameter of master cylinder is needed once you've added the extra volume. You might want to add a handlebar master cylinder to get rid of the under tank one.

IMO the single ATE can be pretty decent if you understand what you have. There's a way to align the pads to get pretty optimum braking.

Kurt in S.A.

Yep, it’s just pretty hard to find a right hand fork for the second ATE brake.

It seems after measuring that the inner diameter of these brembo fork sleeves is too big - 38.6mm, and the ones that are on there are 36mm

The thing has already been updated with a handlebar reservoir/master cylinder, but the brake is TERRIBLE. I can rebuild the ATE caliper (seems pretty easy) but I want to replace all the hand controls and grips with the Walzwerk stuff - not sure if their master cylinder (designed for dual calipers) will work with the single, ATE. I emailed them…will let you know.

This may be the way to go, this seller has a good reputation as far as airhead parts. https://www.ebay.com/itm/265292027843?h ... Sw629hLVOB

I have bought a lot of items from him over the years.

Yep, I’m watching it

Maybe this chart will help:

http://www.vintagebrake.com/mastercylinder.htm

Tom