carb needles...........and the common prob of weak mixtures

[J1MS]

Its surprising how little difference there is between one needle jet and the next available size and how much it effects the running of the engine with a dellorto Carburettor.....My flat slide Dellorto was running a K5 needle with a 135 main and bogged down a little at third to half throttle nothing massive but it could be felt as a slight stutter, above this it then starts to run right.....By changing the needle jet from a 265 to a 264 which is a difference of only 100th of a millimeter narrower, the engine was transformed.....Some people change needles for ones which are shorter or longer and have different tapers (shallower or steeper) and these can have a far greater effect on the engine than the mere 100th of a mm on mine....but such a small change can make a big difference....The pug is a good colour, as it was before, but the engine is smoother and more responsive.....a 100 mile run out today helped with the jetting choice....

[RBG]

Yes mate.
1. yep 7K is about the lot. "I have a feeling that it could be the CDI" but not knowing the limit of the exhaust.

My Franspped Tourer would rev to 8000rpm according to my Pitsch Krober rev counter.

I changed the CDI to one supplied by AF, put an N2 plug in & ran it around.
Then dropped the clip on the needle to the 3rd position, it now runs sub 600C touching 600 on a long strait in traffic
It seemed to bog-down a little when setting off the 1st time but seemed fine after the run.

I've just given it hell in 3rd up into 4th & just short of 8k in top on the Tiny Tack.