Motorcycle very high revving on startup

digger02, Mar 24, 9:18pm
I have just replaced the air filter on my 86 honda GL145 aswell as taking the carb off and giving it a good clean too. Now it only starts with the choke on and immediatle revs very high and loud, and the throttle makes no difference when operated! Any directions I could go to locate problem!

bellky, Mar 24, 9:27pm
oh heck i'll say it again. vacuum leak is my bet

motorboy2011, Mar 24, 9:32pm
the slide in the carb is not lined up properly and does not seat down all the way now! Prob getting caught on the idle screw.

had this happen on an ag100, made for an interesting start seeing it had no off switch!

flat_white_ltd, Mar 24, 9:32pm
Is the thoittle cable seated in properly both ends !
sure the carby slide isn't stuck open !
got all the jet / mixture screws back in !

digger02, Mar 24, 9:39pm
I put everything back as it was before when reassembling the carb. Is the carby slide the piston thing that comes down from the top which varies the air/fuel amount! I'm not 100% on all the mechanical terms. the bike will not idle when not on choke and just dies, throttle does nothing, even manually turning it at carb. thanks for help so far, I will check those things.

flat_white_ltd, Mar 24, 9:42pm
Yes, it is the piston thing.
also.there is a long tapered needle that sticks down from the bottom of the slide.
Make sure it's in the same position, if you can remember, as when you took it apart., & that it fits down into the jet ( the "hole") underneath without jamming the slide.

motorboy2011, Mar 24, 9:46pm
the slide is the round (or square) thing that comes from the top that moves up and town with the throttle, it has a pin coming out of the bottom of it, is the pin there!

digger02, Mar 24, 9:58pm
Thankyou for the explanations, I'm pretty sure the pin is still there, is it likely that the pin is not lined up even though the slide has gone into the cylinder! From what I can remember I couldn't see where the pin ended up as it is hidden when installing, it does have a spring on it though. The logic behind it suggests that the slide would be causing the symptoms ie: stuck in a wide open state. I will check all of that again and try assembling it again with special attention to that. Thanks very much

motorboy2011, Mar 24, 10:01pm
the pin should have a cir-clip so it will not come out of slide, when the throttle is fully closed, its tip will be in the fuel bowel

desmodave, Mar 24, 10:04pm
Im thinking the cable where it enters the carb is hooked up and not seating where it should or the cable has popped out on the throttle end.Eitherwaythe slide is being held up causing it to rev high.

desmodave, Mar 24, 10:05pm
Let us know how you get on

digger02, Mar 24, 10:06pm
Thankyou very much guys, I am slowly learning the basics of motorcycles, I will let you know how I get on, much appreciated.

skippy33, Mar 24, 10:34pm
,that would be my bet to,done this on mates old DT400,trouble was kick start was broken,so had to push start it,fired into life at full revs,left me standing on footpath,plowed into next doors letterbox,lol.

digger02, Mar 24, 10:49pm
x1
Yip guys it was the slide stuck in a funny position, took it off and lined everything up going back in and started no problem. thankyou so much everyone for your input on this I'm so stocked that I could fix it, I thought I'd stuffed it. Much appreciated everyone. all the best to you

flat_white_ltd, Mar 24, 10:56pm
onya !

rob_man, Mar 24, 11:04pm
Ah, the sweet smell of success.
George Harrison.

motorboy2011, Mar 24, 11:53pm
good man :)

therafter1, Mar 25, 3:58am
I wonder how many people on the planet have made this basic error the first time they ever pulled the slide out of a carby.

rob_man, Mar 25, 4:52am
It certainly rings a bell for me.