Arite my nc30 has a misfire all the way through the revs. I've ran out of idears on wat it could be I've cleand the carbs four times, put biger jets in checked the leads they, seem fine and are making a good spark, then new spark plugs to it.it also struggles on start up today it reved really high then cut out i don't think it has sumthing to do with the jet shorly them been bigger it should be puting more fuel into it if anyone could help i would be very grateful thanx

Hi,
Have you checked the choke cable is operating properly?

Hi Josh,

Find it a touch difficult to read your posts man.. Can you break it down a bit?

What was it doing first of all that make you start fiddling with it?

When did it start doing it?

What have you done, exactly, to try and solve it?

Bigger jets is not a cure for anything...

Stick about, you'll learn and we'll help you get it fixed.

sorry mate im not the best with computers well first its been stood for 10 years so me and a mate (who nows alot more bout these than me) have put
new plugs in
new oil and filter
cleaned the carbs and put bigger jets in to get rid of the flat spot that in these bikes
new inlet rubbers from the carbs to the engine block
drained the rad and fresh coolant in
it did seem like it was running on 2 cylinders but all the exhaust pipes are getting hot. there is a missfire all the way through the revs. i hope that's abit clearer its quite hard to ex plane.
thanx for your help

Right...

the biggest thing that stops these bikes working is flooding them. The plugs get killed and it is a very common thing.

What size jets have you fitted? IS everything else standard - exhaust, air filter and air box?

If so, you want to try 118/120 jets.

ALso, when starting the bike use full choke and no throttle. too much throttle will flood the motor and kill the plugs.

So...get them jets back to normal, get the plugs out the bike and dry them on a gas cooker (if you have one) Also, let the fuel evaporate out the bike for a ood hour.

Stick it all back together, full choke, no throttle...and 95% of the time..it will catch...and if it does, let it sit there nad get nice and hot.

Also, starting and stopping it without using it is also bad for the plugs.

Also make sure the carb rubbers are seated and sealing properly. Even a tiny air leak will cause running problems.

Choke enrichment circuit ? Did you taked all chokes out ?

arite ive took the choke cable n put it bk on the same. there a bloke on here that has the same proplem as me im goner try changing all the pipes first make shore no airs getting in

Dude..you need to put it back to standard and go from there.

Does it run now? On all 4?

If not, check the plugs.

arite yeah it runs on all four but when you give it sum gas it seems to bog then piks up with a missfire all the way trough the revs. im getting a race system so if i put the standard jets back in it will make it run lean wont it.
ive had all the plugs out and theres a good spark from them all, im goner try replacing all the pipes, just so i no theres no air leaks thanx