My 125cc moped, direct bikes scorpion I think, won't run without me constantly holding a certain amount of revs, if I just let go of the throttle the bike cuts out instantly. Any ideas ?
Choke on? is it a manual one? Or carb may just need some tuning if the idle screw has moved a little. Find a manual for the carb and see if you can adjust the idle speed. Basically it sounds like its not getting enough fuel at low revs or too much. If the choke is on or stuck open then it will run rich and may cut out on idling. If the idle jet is blocked or idle screw on the carb is set wrong then it won't tick over. Is it okay when cold or does it never tick over?
It's a automatic and yea I've cleaned the carb and it's all fine but that didn't fix the problem. It might be the choke then because when I I get it running for a bit I can let it idle without giving it revs but when I don't warm it up it cuts out every time ???
Pop the electric choke off herbie. when its in your hand and cold ( must be cold ie not been run in bike first) take a measure stick and measure how far down the plunger is from the rubber/plastic collar . now hook the choke to your scooters battery direct and give it 3-5 mins to heat up, take your measure stick and compare the heated measure value to the cold non heated value. heated value is more than the cold value = electronic choke is working fine and correctly. heated value and the cold value are the same or very near = this is your problem the electronic choke has failed and/or is failing this means it can either be stuck fully on or fully off and will cause starting/idle and issues with spluttering and HP power delivery. now if the above works out th e-choke is working fine, you need to look at the idle setting, sometimes what happens is over time with that throttle working 24/7 the cable stretches a bit and becomes a little slack, this inturn allows the cable adjusters to slacken off and unturn themselves , it can play havoc on a riders mind giving symptoms like a failing e-choke / incorrect idle setting / incorrect jet setting . to remedy the problem you need three hands so a buddy of the wife/gf will be of great help, get the scoot started and have the other half just tickle the throttle so its not bugging out. now check the carbs cable adjuster give it a tiny turn to tighten cable and lock it down via the nut. have the third hand let go of the throttle see if it buggs out. if so start up again and now adjust the throttle adjuster at the handle bars very tiny turn adjustments till it holds rpm idle nicley, then lock it down with the adjusters locking nuts and your good to go again.
