Backfire.

[GLscoot]

I am getting a little backfire now and again. I feel I needed a fuel pump with my set up, but I didn't fit it due to the fact I had already built the engine and wasn't prepared to split the casings to fit the pump. I will do this later on. So do you think this is causing the backfire as the engine is not getting enough fuel. I am going to fit a different carburettor to see if this helps.
24mm Stage 6 Carburettor
Reed Valve Manifold
60mm Crank
Polini 180 Barrel
Cosa Clutch
Giannelli Exhaust

[cit205]

You can buy 12v fuel pumps that you don't need to drill the case to fit.

Sure it's not electrical?

[GLscoot]

I'm using the Pinasco Flytech Stator kit which is supposed to set the timing automatically and I do have a problem with the battery frying the loom, so it maybe a wiring problem. Where can you buy the 12v pump from.

[cit205]

I had one from sip , but it was about 10 years ago so i don't know if they'll still do one. it just ran off the regulator output with no need for a battery.

[wack 63]

You can use a vacuum pump and take the suction feed off the reed block below the reeds.

[GLscoot]

Yes, I know that, but I'm using RD250 reeds and they are larger than the standard reed block. So I'm not 100% sure I have enough room. I've actually decided against the pump after reading that they don't last very long, it's estimated 200 hours riding time and they are also prone to leaks.
I've changed the carb to a Del'lorto PHBH where I can fit the fuel line horizontally In to the carb instead of vertically with the previouse carb. It has made a huge difference and the scooter runs fine. Just got to sort out the electrics now.