Topic: 1978 CB 750F SS ComStar, frame, and brake rebuild questions... please help!!

[apetersonboy]

Hey, I'm working on breaking down my 750 comstars and I'm having some trouble getting the rear wheel apart. The mount for the rear brake caliper hangs over the disc and I see no way of removing it. I've looked all over the thing and can't figure it out! The disc comes loose fine, but that caliper hanger is just the last thing that needs to be done. But it won't be done.




Does anyone know how to get this taken apart? I need to paint the wheel, but I can't do so with the disc in the way. Any help would be appreciated!!


My next problem is the front wheel. The wheel came with a crack through the speedo drive. I split the crack open a bit to see the thing fully. See below...




Pretty sure it's unrepairable. I'll just order the whole used assembly on eBay I guess.

NEXT PROBLEM

I'm not sure whether or not I need to rebuild my brakes or not. I know I need new pads, but is an in depth rebuild necessary?




All three of the calipers (two up front, one in back) each have surface rust on the masters. Dunno if I should just scrub it off or what? THANKS!!!

[madmtnmotors]

Take the axle out of the rear wheel, the caliper bracket will fall off.

I'd pump the pistons out of the calipers for thorough cleaning/inspection. If the pistons and caliper bores are not corroded/pitted then just clean-em up and put them back together. New piston seals can be had for less than six bucks apiece from ServiceHonda though...

[apetersonboy]

Thanks for the help! I've tried removing the axel out of the wheel but its easier said than done. It doesn't budge! I've tried everything from Putting the nut on the end and pounding on it with a hammer to dropping the whole thing on the ground. Any ideas? And how does one pump the calipers?

[madmtnmotors]

Axle removal can be difficult when neglected to the point that corrosion has worked it's way in to the axle shaft. Having it pressed out might be good, many have used a block of wood (to protect the bolt) and a big hammer. Once it starts to move it usually doesn't take too much more effort to get it the rest of the way.

To pump out the caliper piston, reconnect the brake line and use the master cylinder to pump out the piston. Remove the pad clip from inside the bracket, then remove the dust seal from the caliper piston, then pump the piston out. You can also use a grease gun by replacing the banjo bolt in the caliper with a solid bolt, loosen the bleed screw, and use a grease gun on the bleed screw to pump the piston out.

[apetersonboy]

Thank you much. Ill give it a good beating when I get home with the wood and hammer idea. And when I pump the master out, does there need be fluid in the resivour? Or can you do it with just air?

[madmtnmotors]

Pretty sure fluid is required. Don't think you can build enough air pressure with the MC to push the piston out. Some have used compressed air, but the compressed air can launch the piston once it starts to move. Hydraulic pressure (MC or grease gun) is much easier to control.