Scooterotica

thanks very much for that ian , all help is greatly recieved ,

told been to by the fella i rebuilt this engine for that its meant to already have a t5 4th fitted

If it ran well with the PM then I`d try that on it again for comparison.
Both the PM and the SIP make peak power between 6500 and 7500 so shouldn`t be that different.
The fact it won`t rev out even in 3rd never mind 4th seems odd.

the pm is gone , its your old engine ivan bought off you years ago bofs , i really dont understand why it wont rev out in 3rd either

is your throttle working ok ,is it fully opening the carb slide when wound back fully

yeah sean pretty sure it is on idle to full open it will rev out quite cleanly

Try a different stator could be electrical and lt coil breaking down under load, relatively easy and quick to change over. Also does it tickover and idle ok?

bazman yeah scooter ticksover an idles ok plus scooter starts bang on one or two kicks

Ok not oil seals then , when it revs out in 3rd does it tend to feel sluggish/not revving out or missing?

its not missing , it flies through 1st an 2nd with ease once you put it into 3rd its feels tight with the more throttle you give it the tighter it gets , its like slamming your foot on the back brake an trying to open the throttle wont go anywhere