Hope this is the right place for this.
I have been asked to look at a mates stuart taylor with an older carb model R1 engine in it. I know less than Nothing about bike engines TBH but willing to have a look anyways.
So the symtoms are it starts runs and idles fine BUT on a trackday warm up lap ( and subsequently since ) it cut out when full throttle was applied and wouldn't start again ( well it might of but he got of the track and had to wait till the session was over.
It then started again Ok in the pits but always just dies when full throttle is applied.
He has had the carbs to bits twice and cleaned them etc and after reassembling the problem still exists.
Sounds to me like there is a lack of fuel ( i.e. no accel pedal pumped fuel) like you get on a car.
OR to much fuel and its strangling itself
OR tps at max throttle is wrong/faulty etc causing ign advance probs. ( coils have been changed already he says)
OR crank sensor issues ( i presume there is one or else how does it know when to spark )

Anyone care to advise on where to look first or anything common to these engines to look for?

Thanks in advance and don't be to harsh on me as I don't come over to the dark side very often

Start with plugs mate you wouldn't believe the diff a set of plugs makes.

Try driving the car at quarter throttle right to redline surely that should check TPS

hoping to look at it today or over the coming week. How is the extra fuel required during 0 to 100% throttle ( snap from 0 to 100) supplied by bike carbs?? Is it visible like say a 32 36 dgav?

Another thing to look at is if it has a open filter then the air compensation jet will need blocking off the jet is located in the carb near the butterfly it's the one in the middle at the bottom !!

Otherwise it will over fuel loads at about 5-6k