Unable to Restart when hot?

[sclay115]

Pulling into the garage tonight after about 20-25 min of riding, I stalled it coming up the driveway (sloped) and went to restart and it wouldn't start again...is this just a common problem with carbs in general? Or is there a remedy to this situation?

Steve

[andrewsw]

remedy? yeah, don't kill it

seriously, though, I never have problems with it not restarting. you've definitely got something going wrong there. How was she running otherwise?

[sclay115]

Oh it's running fine otherwise, a little hesitation in the lower revs, but I think that is just some fine tuning. It really runs likes a top though, haven't had one complaint besides the hot start issue since I got it running. Are there any obvious things I can check on it that might be the problem?


Steve

[andrewsw]

if you're getting some low end hesitation, that may be a mixture problem in the idle mixture screws, mis-adjusted float level, or maybe an incorrect pilot jet size. this assumes that there aren't other problems like worn emulsion tubes or slides or other actual "problems" outside of simple adjustment issues.  

what rev range is it hesitating in? how does it behave when blipping the throttle off idle does it stumble or do the revs hang high? is the air filter clean?

I would imagine that its possible to have starting problems if you're too far out in the idle and super-low-end range, but that's just a guess. I still think you might be facing and ignition CDI problem too, but others know more about these things.

these B4's are very sensitive to very small adjustments in the carbs, especially in the low end. but once they're right... sweeet.

[sclay115]

Well it's more like starting off in first, twist the throttle, nothing for just a moment, then it just takes off. Sort of strange looking on the road I’m sure. But I just ran into another problem today. Parked it outside my girlfriends place, and I get on it to go to work, and it wouldn't start. It would crank, but not fire. I got it firing once, but I could keep it running, I tried the throttle but to no avail. I’m guessing most of these problems are stemmed from one issue, the no hot start, and now the no cold start. Seems strange really. I’m going to try to swap the plugs first. oh, and the CDI box, has already been redone by whoever across the pond, it's got their label on the back, so that's a good sign at least, so now it's just off to check the coils/wires/plugs.

Steve

[andrewsw]

gremlins. its gremlins for sure.

A

[sclay115]

Seriously apparently so. Because now it runs/starts fine. I guess the carbs need to be tuned a bit more, but other than that. Runs great. And let me tell you what, it feels so awesome to be able to enjoy it.

Steve

[andrewsw]

     

[gallant_pilot]

hey buddy !

i know it has been years from this post but if u still on the forum,plz can u tell me what u have done to the carbs finally?
it seems that i have the same problem exactly and i dont know where to touch.

tx

[Squishy]

Turn the mixture screws in and see what happens.
Also check whether the choke mechanism isn't stuck.

[gallant_pilot]

mixture is set properly.
just realized when the bike is hot and fan is ON,it drains the battery which doent let the starter to crank it properly,the moment i leave the bike for few min,it starts.

[gallant_pilot]

by the way !

i found pinholes in my diaphragms in 2 of them.
what will it do to the bike and how can i fix it.
in this country we dont access the parts to replace them.
is there any kinda glue which i can use on it?

[Squishy]

mixture is set properly.
just realized when the bike is hot and fan is ON,it drains the battery which doent let the starter to crank it properly,the moment i leave the bike for few min,it starts.

How do you know his mixture is set properly??
Also your battery was drained it doesn't magically regain it by waiting a few min.....

[gallant_pilot]

mixture is set properly.
just realized when the bike is hot and fan is ON,it drains the battery which doent let the starter to crank it properly,the moment i leave the bike for few min,it starts.

How do you know his mixture is set properly??
Also your battery was drained it doesn't magically regain it by waiting a few min.....

as u recommended in my other post, i set it with regards to manual.stock setting.1.5 turn.i cant make it richer!
but about the battery,u might not believe,but in few minutes it will gain its charge back.i am also wondering how it might be possible.but the moment the engine is hot and i switch it off.then while starting the battery shows that it doesnt have enough power.after few minutes it cranks it nicely !

[Squishy]

mixture is set properly.
just realized when the bike is hot and fan is ON,it drains the battery which doent let the starter to crank it properly,the moment i leave the bike for few min,it starts.

How do you know his mixture is set properly??
Also your battery was drained it doesn't magically regain it by waiting a few min.....

as u recommended in my other post, i set it with regards to manual.stock setting.1.5 turn.i cant make it richer!
but about the battery,u might not believe,but in few minutes it will gain its charge back.i am also wondering how it might be possible.but the moment the engine is hot and i switch it off.then while starting the battery shows that it doesnt have enough power.after few minutes it cranks it nicely !

Well this topic is not about your bike now is it??