Hey guys,

My main goal was to get the bike to at least idle and run. Now my goals are fine tuning the bike to run like back in 90's I recently noticed that this bike has absolutely horrid throttle response. When the bike is at low revs (around 1.5k rpm), when I give it throttle slowly, I can rev it like crazy. But when I give it throttle suddenly, it sputters and the revs drop to a point where it stalls. My 110cc pocket bike has better response :0 Is is because the bike is running too lean? Or do I need to re-sync the carbs? I've eliminated the vacuum leaks so that shouldn't be a problem. However, one thing I have to note is that I didn't have much gas in the tank. But I'm sure the float bowls were full at the time. Any suggestions on what is wrong?? Thanks

 

the carburators could be horribly out of sync, when you open the throttle, your opening the butterflies and if your a/f mixture blows your motor won't have a clue what to do with it. That or your spark plugs are bad and not igniting hot enough, or like me your coils blow...

 

Synced the carbs today and I'm still getting the problem. I think it might have to do with the pilot screw adjustment because I only see this problem in the 1000rpm to 2000 rpm range.

 

What are your mixture screws set at? It might be a little rich at idle.

 

I had the same problem. Once I could get the bike running it would rev like a motha! But if I tried to goose it, it would bog almost to the point of dying. I'm trying everything...let me know what works for you.
Fyi, mine was at 2.5 turns out on each carb before I had running issues and it ran perfect!!!

 

im jetted running 2 turns out. But if its dieing with throttle, check your air filter

 

Hello Everyone. I too have this same problem. My bike idles like a dream, "with no choke on" and as soon as i try to "suddenly" give it a good twist on the throttle it sputters and dies. Sometimes at the same time it's dying... it will give a "small backfire" and manage to make it back to an idle. I haven't changed the plugs yet so maybe that's the culprit? Would a contaminated air filter do this? Some tips on this would be very helpful. I'm trying not to spend... Thanks in Advance. and just curious what your status is on your bike subyman1440? Any Success?

 

Trust this coming from a guy that extinguishes all other avenues before buying parts...if your air filter looks good, buy new plugs. Even non-iridiums will wake your bike up! And your nightmare will be over. Btw, 2.5 turns out should be good...you can fine tune it from there once you get the new plugs in.

 

I had the same problem with a few quads I have been working on for my inlaws. The quads had been sitting outside for a year or so without being run and the carbs got all gunked up. I cleaned them and they would start and idle fine but as soon as the throttle was opened, they would die. I cleaned them both real well again, this time replacing all seals as well as the ones on the fuel mixture screw (the D shaped one next to the float bowl) and the air mixture screw. I sent them both to two and a half turns out (the air needed a little adjustment once it was on for proper idle) and everything turned out fine!

I would suggest setting the fuel mixture screws to default (two and a half turns out from being "lightly" seated) and see if that helps at all.

 

My problem was the petcock had been replaced and the stock screen/filter in it had been removed. there was a aftermarket inline fuel filter installed with waaaay to much slack on the main fuel supply line. i removed the tank/hoses and cut the extra slack back to where it would be gravity fed as it is supposed to be. put it back together and it fired
right up! NOW IT IDLES AND REV'S FINE....
LESSON LEARNED-DON'T FORGET THE SMALLER THINGS....