Right, my nc30 is up and running, taxed and MOT'd and runs pretty much perfectly most of the time, however.......... if I take it for a run its fine, runs sweetly, pulls well in all gears, nice and smoothly, then out of nowhere the power drops off and after a few hundred yards it dies completely. the 1st time it happened I put it down to a dud battery and reg/rec and have since changed them both, but the same thing happened the other night when I took it out with a new battery and reg/rec fitted. I have plenty of fuel in the tank, and the carbs have been cleaned and it runs fine the rest of the time. does anyone have any suggestions on what to look for?
once it dies, it starts up again and rides fine after a few mins before doing it again yes ? not trapped the tank breather pipe have you ? very common for them to not be routed correctly and they become crushed which causes a vacuum in the tank. the other thing - it is worse when hot ? if so then replace the vacuum pipe from the block to the fuel tap - they go soft and collapse over time again restricting the tap flow / starve the bike of fuel. do NOT be tempted by the HRC fuel tap mod though, you have been warned.
I echo what CRM says. The fuel pipes degrade and the inners collapse under heat. Had the same on my beloved GPX750 took me an age to diagnose as the pipes looked to be in good condition visually.
the fuel line is new, I have a tap repair kit on order to rule that out, will have a check on the breather / vacuum pipes when I get a chance, looking back both times it happened was just after id gone round a roundabout so could be related to that possibly?
not the fuel line - the vacuum line which makes the tap operate. from the fuel tap there is the main fuel feed, but on the other side of the tap is a smaller diameter pipe which goes to the intake on cylinder 3 if i recall - this always collapses and kills the vacuum and as such the fuel tap cant work. tap repair kit is a good idea, often some butcher will remove the spring and turn it around to simulate the HRC mod to allow better fuel flow or because they are too tight to replace the pipe. sadly this also does not shut off the fuel when not running. all it takes is one leaky float (and i bet you at least one does) and the motor fills with petrol. not good.
I'll get some hose ordered for the vacuum pipe and hopefully with that sorted and the tap repair it'll be ok. the short runs I've actually done on it have me grinning ear to ear. just gutted I'll be away for the next 3 sisters trip cause I really wanted to give it a run round there
hope you got 090's fitted for maximum grins ? 092's are fine for winter but have no place on a bike in summer.
