New bike = new thing to tinker with.

[Nessism]

Classic source of air leaks is from the large O-rings sandwiched between the cylinder head and the rubber carb mounting boots. It's almost 100% certain that yours are leaking if they are the originals.

[salty_monk]

Also check the throttle cable is adjusted correctly & not holding it open a little... there should be about 1.5mm play in it.

Dan

[AceFrehley03]

Hey Dan -

The throttle cable has about .5mm of play in it, lol. It's pretty tight. I'll loosen it up a little bit and see where that gets me.

I'm getting it to start pretty consistently now, it's just that it likes to run itself straight up to 6,000+ RPM. Not cool. It gets started, tachs up, and gets shut right back down. A couple times I've gotten about 2,000 RPM and have used those times to check for vacuum leaks.

I'll tear the carb mounting boots off and see if I have an o-ring issue there. I haven't replaced it but I really wouldn't doubt that they are original. I haven't even had those boots off yet.

Another thing worth mentioning is that the idle screw has no effect absolutely. None whatsoever. From all the way out to all the way in.

I'll go adjust the cable first, see where that gets me, and then probably work on tearing the carburetors off (again, ugh) and see what's up.

Thanks all. Pics will come soon, I 'spose. I'm going to start documenting this thing, I'm at wits end.

[nabrams]

Another thing worth mentioning is that the idle screw has no effect absolutely. None whatsoever. From all the way out to all the way in.

That may mean your throttle pulley (the one the throttle cable attaches to) is stuck in a partailly open position. Verify that the throttle plates are FULLY colsed when you let go of the throttle.

[AceFrehley03]

Haha, victory! It turned out that it was a combination of intake manifold o-rings and the smaller o-rings inside the carb. Got the bike running, tuned, and now all is well.

Now that it's running and driving, I have assured myself that it has all the gears, the clutch is tight, front brakes work good.. and I lost rear brakes.

When I bought the bike all three brakes were frozen. The front two got rebuilt and they're fine now. The rear caliper was also rebuilt and put back together. I couldn't bleed it though because of the master caliper being frozen.

Well, I finally got the master cylinder out and apart and the cup is actually stuck inside of the master cylinder all the way in! I can't get it out with ANYTHING. Is there some trick to this I'm missing? I've used WD40, compressed air, I can't get it out with anything. I'm not going to ride the bike (far) without rear brakes because I live amongst a TON of hills. I'll take it down to put gas in it (<1 mi) but that's about it.

Any ideas? I've searched and haven't found much about actually releasing a frozen cup. Also, since I'm at it, the dust boot is torn about 1/8". Will that prevent the rear brakes from functioning, or will it just let them get dirty?

[nabrams]

Stuck piston in caliper: Very common problem.
First get it off the bike.
Measure how much piston is sticking out.
Then put a 2x4 piece of wood over the piston (the "cup"). Whack the hell out of it with a heavy hammer. Measure again. If it's lower (less sticking out), then you've loosened it.
Even if it's not lower you still might have loosened it.
Now hook it up to the brake line, bleed, and pump it out using the brake lever. Air is much more compressible than liquid and will have a harder time budging that piston.

[AceFrehley03]

Hey Nabrams. Thanks for the great advice. I managed to rebuild/reseal all of the calipers without issue. Front brakes are great now. I'm having a hard time with the rear master cylinder behind the side cover, above the right footpeg.

On bikebandit.com the blow-up diagram shows a spring assembly as being inside of the master but I can't see that. It's stuck inside and I can't get it out. I got the rod (the one with the half-dome top) out of the cylinder fine but I can't get the rest out. It's rusted in there. I tried blowing it out with compressed air but didn't have any luck. I'm probably going to have to use water and try to hydraulic it out, and find a few solid bolts to fit the threads. Any other ideas, or is there a trick to getting this thing out? I've practically bathed it in WD-40, have worked on it as much as possible and still have no luck. Any ideas?