Author Topic: Honda C100 Running Problems  (Read 654 times)

Offline 1966g10

  • Posts: 15
Honda C100 Running Problems
« on: May 22, 2013, 20:48:24 »
Hello all,

I have a 1965 C100 and I got it from a guy that had it in his basement for 10 years. I got it running, changed
the spark plug, cleaned the carb real good. looked over everything. I can get it run. And thats about it. The carb adjustments must not be anywhere close, Its hard to start, then once you have the throttle pinned it will start and rev kinda high in netural. I wanted to let it stand alone and run before I tuned anything, but after about 45 seconds the RPM's slowly drop and the bike kills itself, every single time. Can anyone help me please?

Offline nrcb125

  • Posts: 280
Re: Honda C100 Running Problems
« Reply #1 on: May 22, 2013, 21:14:49 »
I had a similar problem with my CB125S when I picked it up. The brass float had small pinholes in them from sitting for so long, so the float would fill with gas and not float at all.

I'd say double check every part of the carb and also check the petcock.
'73 CB125S - current project
'99 EX500 - Race Bike

CB125S build thread (haven't updated in 5ever):

Offline AlphaDogCustoms

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  • Posts: 3359
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Re: Honda C100 Running Problems
« Reply #2 on: May 23, 2013, 08:46:33 »
You may still have clogged passages. The idle circuit can have a very tiny orifice in the jet that may still be clogged with varnish.

Did you set the float height?
...every dump I take is original too, and it doesn't smell any better because of it's originality.

Alpha Dog Custom Cycles
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I'm so old, I even know what ignition points are.