Rearset leverage

[cowboysculptor]

This seems like a topic that has been discussed, but I haven't found a decent answer in the threads:

I installed a pair of Tarozzi rearsets on my '78 cb750f. The rear has disc brakes, and I'm finding I have no stopping power in the rear at all. It feels as if I'm not getting enough leverage with that short brake lever.

Aside from reinstalling the stock brake assembly (which in the case of my '78 supersport includes a long, ugly aluminum mount), what can be done about this? Would a larger master cylinder do the trick? Would I then also have to invest in matching calipers? Or is there another answer I'm not finding?

All help is appreciated, my hydraulics knowledge is mighty limited.

 

[Bozz]

How far is the MC shaft traveling?

Are you absolutely 100% positive that the system is completely bled?

Steel lines?

My rig work fine with only 8-9mm of shaft travel.

Your results may vary...

 

[Rattlecan]

Sounds like you still have some air in the system.
You can try and bleed them with the caliper off the bike, just place a piece of flat metal between the pads and lower the caliper to the lowest point you can, this way any air in the system will naturally move up twards the master, then you can crack the line bolt at the master by the top you may have soem air trapped there, and from that point you should be able to bleed the system in the conventional way.

You should be able to lock up your rear brake fairly easily as long as the clutch is pulled.

You can also invest in one of these brake bleeders for about $100 and they work awesome. They actually push the fluid up from the caliper into the master completely eliminating any air in the system.

http://www.brakebleeder.com/products/featured-products/v-12-diy.html

This is the cheaper model for most guys at home, and there is a pro model as welll which is really cool.

Hope this helps.

 

[cowboysculptor]

Sometimes the problem is something seemingly unrelated . . .

I pumped nearly half a jug of brake fluid through the system, but still the same results. I took it for a spin, and when I got back found that there was a tiny leak in an oil hose. That oil ended up all over the brake disc. It was lubricating the brake system nicely!

 

[VonYinzer]

HA! That'll do it. Glad you found out the easy way, and not from the back of the truck ya slammed into!

 

[cowboysculptor]

No doubt! SO, if anybody has a spare cb750 oil line kicking around . . .