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View Full Version : alteration for coaster brakes ?



Gerald_G
07-02-2008, 08:57 PM
Has anyone considered running two diagnal braces from the fork to the crank instead of a bent bar over the top of the tire ?

This would allow for coaster brakes.

Any thoughts ?

robertwb70
07-02-2008, 09:21 PM
Normally the chain stays (the horizontal tubes that go from the axle to the cranks) are there in addition to the top bar you mention so it would be no problem to attach the coaster brake anchor. The real question is whether or not it would be a good idea. Maybe someone that has tried it can tell us?

Gerald_G
07-02-2008, 09:25 PM
Ah - thanks for mentioning the word "chain". I'd not really considered where the chain would be. I'll carefully consider it before thinking of changes.

Does'nt the top bar normally weld on to where the brakes would mount ? I read in another thread somewhere that coaster brakes were not an option ?

robertwb70
07-02-2008, 09:43 PM
I see the problem now- it's just terminology -coaster brakes are the ones in the hub that work by pedaling backwards (I think). Brakes that mount at the point where the forks "y" with a single bolt probably could be made to work by doing what you're thinking if I'm interpreting it correctly. It may be easier to use V-brakes or cantilever brakes since they mount on the fork tubes. Canti's would probably work best due to their cable arrangement.

I don't think there's any real need for brakes on these machines though, it drives me crazy every time I show someone my spincycles and they ask "where are the brakes" and "how do you stop".

If you put fixed wheels on the rear this would become an issue but with casters on the back even if you brake the front wheel the rear end is still going to come around, which is no different than just initiating a spin anyways- either way you stop pretty quickly but it does require some planning to control where you end up.

Gerald_G
07-02-2008, 09:54 PM
ah thanks again.

Your right, I am thinking of the kind with a cable and handle. I was hoping to re-use the brakes from the donor bikes. My plan is to make a changable arrangement on the rear for having fixed or castor wheels so I want brakes. I'll keep thinking / measuring.

robertwb70
07-02-2008, 10:16 PM
If you're stuck with caliper brakes I see 2 options off the top of my head

1-make the top tube go to the gooseneck instead of the top of the fork "Y"-this would entail making that brace at least partly movable/removable in order to be able to disassemble the bike- or not if you don't ever plan on taking it apart.

2-attach the brakes up near the bottom bracket, probably upside down on a bridge spanning the chainstays could be made to work, my LWB recumbent has V brakes in that area, but being so close to the cranks might make this option harder or even impossible you'd have to mock it up and see.

SirJoey
07-03-2008, 06:40 AM
Brakes were an absolute necessity for me, especially on this one, as I didn't really build a "SpinCycle" at all, but a SWB delta. In fact, I didn't even put casters on it.

I must credit "BikeFranklin" (Dave Stout) with the idea, as well as his kind donation of the parts that made it possible, but here's how I built my second "SpinCycle" as an 18 speed, & still retained a brake, by using a small suspension bike rear triangle as the front end:

http://img388.imageshack.us/img388/2941/07qm3.jpg

http://img388.imageshack.us/img388/4599/06kh8.jpg

http://img384.imageshack.us/img384/7131/sirjoeysigmedij1.gif