Brake improvements...

[pjmcburney]

I'm sure I've read it in a couple of places - can the GT750's stock (disc) brakes be improved by sleeving down the stock master cylinder?


I think 14mm is the go?

Any info appreciated - I'm wanting to improve my brakes but not go too far from stock.

[jabcb]

VintageBrake has cylinder ratio recommendations.
http://www.vintagebrake.com/mastercylinder.htm

[tz375]

If I read that correctly, a pair of single 38mm piston calipers will need an 14 or 15mm master cylinder to get in that sweet spot and a GT550 with a single caliper would need 10-11mm master cylinder.

A 5/8" master cylinder would only create a 11.46:1 ratio which is a little wooden and requires excessive force.

I upgraded mine from single piston single sided calipers to twin piston SV650 calipers and used a stock sized 5/8" master cylinder with light Honda CBR600 disks. Braking is much better than a stock bike in terms of feel. It's not too light which is an issue for those of us who have learned to grab a big handful of brake lever and squeeze it as hard as we can.

At the top end on the drag strip, my old bus is doing around 110 and there's enough brakes to haul that down for the exit road in pretty short order.

Braided lines are a must and it looks like a smaller M/C would be a good step.

[pjmcburney]

Thanks blokes.


I thought 14 or 15mm would be right - I'm sure it's been mentioned here before.

I already run braided lines.

Now, the MC sleeving is likely the easy part.
Anyone have an idea about what piston/rebuild set to use with a sleeved-down GT750 MC?

[tz375]

I guess that if you want it to look original, sleeving is the only way to go, unless you find a GT550 M/C in good condition. If originality is not an issue, grab a new M/C off ebay. Probably cheaper.

[pjmcburney]

Richard,


Is the 550 MC 14mm?

[tz375]

I don't have one, but I believe so. Ask Coyote Chris. He knows way more about 550s than I ever will.

[pearljam724]

Firmer fork compression vastly improves the stock brakes too.