nc30 lost its top end power ! any ideas ??

[igoe1975]

Hello, riding my nc30 today giving it a good old thrash when it suddenly decided to lose its pulling power past 7000 revs ! It runs as normal at lower revs but as soon as you hit 7000 revs or so it seems as though its lost some power . It doesnt bog down or anything and does rev through to the redline just takes longer than normal and the engine / airbox sounds noisy , did notice before this happened earlier in the ride that at a constant throttle at about 7000 revs also that it wasnt holding a constant speed it was gaining and losing a couple of mph . Does anyone have any ideas as to what it sounds like ? Cheers

[Dynamohum]

Check the vacuam pipe from the tap to rear inlet first .

[Neosophist]

as above.

check vaccium pipe first (perhaps replace it if its old uknown conditon, its chepa and causes many breakdowns)

have a look in the tank see if you can see any obvious blockage.

secondly check the battery voltage at idle and some revs, make sure its not overcharging as that will kill ecu and alters how the bike runs

[igoe1975]

Thanks for your replies, mrs got me wall papering this bank holiday ! She'll kill me if i piss off in the garage working on the bike . Will have a tinker with it when i get a chance and let you know how i get on .

[igoe1975]

Ok, got a new vacuum pipe off rick oliver, fitted it and took the bike out quickly for a bit and the first time i accelerated on a short bit of road it felt like it was still not pulling properly but only managed to get to about 9000 revs because of traffic but as soon as i got on an open road and tried again it was absolutely fine so turned round and repeated the run about 4 or 5 times and all good ! Did check the old hose and looked fine although the new one definitely is a tighter fit , so thanks for your replies and suggestions .

[VtypeV4]

Nice one, another lives to fight a new day..

[Neosophist]

Ok, got a new vacuum pipe off rick oliver, fitted it and took the bike out quickly for a bit and the first time i accelerated on a short bit of road it felt like it was still not pulling properly but only managed to get to about 9000 revs because of traffic but as soon as i got on an open road and tried again it was absolutely fine so turned round and repeated the run about 4 or 5 times and all good ! Did check the old hose and looked fine although the new one definitely is a tighter fit , so thanks for your replies and suggestions .

dont rule out electrics.. multimeter on the battery and check voltage running and at 5000rpm (in neutral on the stand is fine... )

if its overvolting it can and will kill the igntion box eventually.

hopefully you already fixed the issue but much better to be safe than sorry

[igoe1975]

Yeah your right , will check it over the weekend .

[crookzy1]

Ok, got a new vacuum pipe off rick oliver, fitted it and took the bike out quickly for a bit and the first time i accelerated on a short bit of road it felt like it was still not pulling properly but only managed to get to about 9000 revs because of traffic but as soon as i got on an open road and tried again it was absolutely fine so turned round and repeated the run about 4 or 5 times and all good ! Did check the old hose and looked fine although the new one definitely is a tighter fit , so thanks for your replies and suggestions .

dont rule out electrics.. multimeter on the battery and check voltage running and at 5000rpm (in neutral on the stand is fine... )

if its overvolting it can and will kill the igntion box eventually.

hopefully you already fixed the issue but much better to be safe than sorry

Sorry to hijack the thread but mine seems to be doing this (hitting 15.3V+ at times). I have a mosfet regulator I think from an R6. Is there any alterations that can be made to it, or is the answer simply to replace it?