Topic: SOLVED Newbie Intro and Throttle Issues--Revving out of control

[cheeseman]

Thanks Deltarider.  Yes, I did check out the ignition on that cylinder. It all looked good.

As this occurred immediately after I was messing with the carbs, I'm pretty sure that's the cause.

I'm just wondering if I should be targeting the main jet or valve/seat/float when I get them off again.  I'm seriously considering pulling that aftermarket junk off and just cleaning up the old main jets and using those. They were just a little corroded. And then get some quality needles/seats.

[IrocRuss]

I've been working on restoring a 1972 CB500 that I rebuilt the carbs on.  Bike wouldn't start (had aftermarket rebuild kit).  Posted a question about kit and HondaMan responded.  This is probably relevant to your issues.  On a second note (this is just my thought about cylinder that is cold), I had 3 of my 4 overflow tubes that were cracked, one was a more noticeable crack that went down the whole tube.  I wasn't clear if you fixed your gas leak to overflow tubes.  If one of these is cracked, and the float bowel level is always to low, I wonder if cylinder not getting enough gas for combustion?  Also on the float seats, they can get pitted (separate issue from dirt), one of mine was pitted fairly bad, I'm sure it wasn't sealing well.  I still haven't worked out the not starting issue, but seems the new aftermarket carb kit is the issue.  Here's a link to my original post:
[url][http://forums.sohc4.net/index.php/topic,182292.0.html/url]

[cheeseman]

Thanks IROC

Yes, I did check those tubes. Filled up the bowls before reinstalling and they held. I put the bowls back on the carbs and bench tested it by gravity flowing some gas into it from a gas can. They held.  After putting them back on bike and driving a few miles, one carb began to overflow, but not the "cold" cylinder. That junk seat or needle no doubt.

Thanks for the link--it helps.

Good luck getting yours running!

[newday777]

Any ideas on why the one exhaust pipe is cold?  Does that mean that cylinder is not working at all (it was before I messed with carbs). If so, would it be because the "new" main jet or needle/seat is not functioning?

Thanks for any input.

Did you set the float level when you changed the needle and seat sets? Float level needs to be checked/set with new needles and seats. Overflowing can be a float level issue or clog in needle seat from garbage/rust particles in the tank.