i've tried everything i can think of [bar one], to get this sob running right, but it will not rev over 3000 revs. it just starts sort of blubbering, gives and almighty backfire and then stops. i rebuilt the vm28 carb as a normal one, with the main jet where it should be, instead of in the floatbowl
![Smile :)](./images/smilies/icon_smile.gif)
i shortened my homemade header pipe by 100mm to the length i eventually worked out from jenning's book. i put 2 new pulser and primary coils on it, a cdi off a good running ts185, at the advice from a ts400 owner i went down from 180 main jet to 170, it was still flooding terribly. i lowered the needle to its lowest position and even dropped the float height by 2mm, from 15mm to 13mm. it's now stopped flooding and sounds a lot crisper - up to 3000 revs. i changed coil to a twin spark, it made starting a lot easier, but still 3000. engine has new mains and seals in it - i built the bottom end, then left it overnight with the crankcases full of parafin. in the morning, no leaks anywhere, so tipped it out and rebuilt the top end [new piston kit and bore is fine, measured the ring gaps and they were well below max]. the only thing i haven't changed is the supposedly good cdi - because i haven't got a spare
![Very Happy :D](./images/smilies/icon_biggrin.gif)
the engine will idle when it's warm at about 1500 revs and starts usually first kick. i've just run out of ideas why it won't rev over 3000
![Crying or Very sad :cry:](./images/smilies/icon_cry.gif)
any suggestions gratefully received.
cheers, dd.
p.s. i've ordered a new 160 main jet to try and it already has a new #25 pilot jet in it.
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