NC30 Running problem

[rabutcher]

I finally got to take my bike out, in 1st when it got to about 5,500rpm it was real juddery but would go through it, then in any other gear it wouldn’t go past 5,500rpm.
So I took the carbs out cleaned them adjusted the float height, took it out again still when it gets to 5,500rpm judders but will now rev past 5,500.
Under 5,500rpm it runs fine, revs ok in neutral, has new filter and plugs.
Only thing i can think is the carbs need balancing, but not 100% sure any input would be great.

Thanks in advance

Rob

[CMSMJ1]

This is the speedo disconnection problem.

Have you got a speedo? is it plugged in? if you have a derestriction box make sure that is plugged in too.


The rear cylinders cut at 5.5k revs if the bike senses no speedo...

get checking!!

[rabutcher]

thanks for the quick reply, yes i have a speedo, and it seems to work. there some small black box behind the clocks which is plugged in, in replace of the connector coming out the back of the speedo.

[wullvfr]

thanks for the quick reply, yes i have a speedo, and it seems to work. there some small black box behind the clocks which is plugged in, in replace of the connector coming out the back of the speedo.

the problem may lie within this,check it over and make sure everything is hunky dory.as cm says,the problem sounds like the "limp home mode" where the spark is cut to the rear two cylinders when it roughly hits 5000rpm.


william

[Drunkn Munky]

this happened on my nc35 all of a sudden whilst riding. turned out the exhaust had melted through the rear brake switch wire which somehow caused my indicators to flash fast and wouldnt rev past 5500. dunno why it caused the bike to do this but check your wires if you've checked everything else

[CMSMJ1]

thanks for the quick reply, yes i have a speedo, and it seems to work. there some small black box behind the clocks which is plugged in, in replace of the connector coming out the back of the speedo.

Plug the speedo straight in and see if it cures it. If so, you need a new 112mph derestrictor

[rabutcher]

thanks for the quick reply, yes i have a speedo, and it seems to work. there some small black box behind the clocks which is plugged in, in replace of the connector coming out the back of the speedo.

Plug the speedo straight in and see if it cures it. If so, you need a new 112mph derestrictor

Took it out today, and also balanced my carbs using the drill bit method. now run's fine

thanks again