Choke or Not to choke that is the question...

[FREAKS_UK]

Hi to all you pit bike freaks out there Im kinda new to the pit bike scene i just got me a 125cc or maybe a 110cc pit bike was told it was a 125cc 2006 model is there anyway i can tell by looking at the engine if its a 125cc OR a 110cc??? and here is my MAIN question...This is from starting from COLD I turn the key on... I put the choke ON ( TURN UPWARDS ) then i hold in the front break and press the electric start and it does try fire up but then just seems like it dont wanna run proper without me giving it some revs but it still dont sound right??? Now if i start all over again and...Turn the key on...I put the choke to OFF ( TURN DOWN VERTICAL ) i hold the front break in the push the start and it starts up fine and maybe give it a few revs and it ticks over fine...So please can anyone tell me if its really such a BIG DEAL to use the choke and turn it ON??? cant i just leave my choke in the OFF position all the time??? Ive read so many posts on here about having to mess with the carbs and no one really fixing the problems they get same as me with choke i just thought i would post my own message in more detailed terms from a newbie and maybe other newbies will learn just like me

 

[Flarry]

Look on the right-hand side of the bore (at the front of the engine) and it has the engine size stamped onto it.

You dont have to use the choke but its usfull for starting a cold engine, if its not working then it needs some fine tuning, but you can warm it up by reving with the choke off just the same I guess.

 

[cass38a]

If you try to start it cold without the choke it will probably be hard. When i start my bike I use the choke to start it but I turn it off after only about 5 seconds.

Your engine should have a little casting showing 124cc or 107cc on the cylinder.

 

[FREAKS_UK]

Well as i cant even start or keep my bike running with choke ON does that mean i got problems? should the bike be running with a high idle speed when you have the choke ON? becuase when i slowly turn the choke from OFF to ON it starts to die out??? or maybe i got the choke settings wrong??? all i know is that when i set the choke FLAT (HORIZONTAL) the bike starts fine and idles perfect really slow idle just seems like it wants to cut out but it dont i see alot of posts about messing with the carbs and not many people having much luck maybe its best to leave the carb alone once you got the bike running ok even if when you turn the choke on it dies??? or maybe im wrong??? And to that guy who said about my engine size i found a stamp and it says I.X 107mL thats all? so what does that mean?

 

[cass38a]

It means its a 110.

 

[MILLPIT]

If it starts and runs fine without the choke then don't use it. All it does is give the engine more fuel than normal for easier COLD starting, and increases the idle speed. I do the same thing as Cas38a and only use it for initial startup and switch it off after bout 5sec.

 

[Flarry]

If it starts and runs fine without the choke then don't use it. All it does is give the engine more fuel than normal for easier COLD starting, and increases the idle speed. I do the same thing as Cas38a and only use it for initial startup and switch it off after bout 5sec.

Well actually, with the butterfly valve (like FREAKS_UK has and I have) it gives the bike less air which makes it run richer which makes it idle higher.

I have the same problem, I think it has to do with carbys with a butterfly valve, the chinese mikuni carbs have the butterfly valves and most of the jap made mikuni's have the plunger choke.

 

[pegleg]

It doesn't matter what sort of carby you have they all do the same thing, weather it be more fuel or less air, having less air changes the air/fuel ratio which means more fuel.
Once the bike is started, and it runs fine with the choke off, leave it off.
As stated by cass and millpit, it is only used as an aid to start a cold engine. If an engine is idling then turning the choke on will only restrict the air flow which intern will "choke" or "die out" an already running warm engine.
As the other boys have said, use it to start the engine if you need to and then turn it off after initial start-up. There is nothing wrong with your carby, it is functioning as it was designed too...

 

[FULL-ON]

I never use the choke and it starts first kick every time