just serviced my nc29.
changed oil + filter, cleaned rad + fresh coolant
changed plugs, put ngk iridium ones in gapped to 0.8mm as per haynes.
basically the second i started it up after service didnt feel right.
it doesn't rev right at all, feels lumpy on tickover,
occasionally misfires and cuts out.
but if you get it past 4000rpm when your riding it fine and will rev cleanly to redline.
was reading threads below about valves and clearances??
its literally onli after i did the service...
cheers
Laz

I know it sounds bone, but check your plug caps are on tightly, something as stupid as that can throw it off. Have a feel of your downpipes, see if they feel equally hot on start up/idle. If not you know where your problem lies. Or it could be crap in your carbs, but really its just a method of elimination. Start with the easy stuff and rule them out 1 by 1.

At least that's what I would do.

the spark plug gap may be wrong as you have fitted ngk iridium plugs,the manual specifications will be for standard ngk plugs......just a thought



william

cheers martyn,
had another look today all the caps popped on nicely and its misfiring on one cylinder cant work out which...
william - very good point, cheers for that didnt reli think of it, i reckon a call to mr gf is the inevitable.
cheers
laz

Could be the HT leads (or just one of them) Check the resistance in them.

On my NC29 trackbike one of the Ht's got too high resistance and its got a bad idle...

whichever downpipe is cold will indicate the one that is misfiring....or coller than the others.

check the primary connection on the coil,i had this problem on the nc30.the connection kept popping off the coil and i had to make a new connection.


william