Bike wont rev over 5k, help!!

[Tom1]

So ive had my nc30 for 18 months, completely stripped the bike, powercoated the frame, new end can (tyga maggot), new fairings, new speedo, different sprocket, changed oil and filter, new spark plugs etc etc.

Put the bike back together thinking it will be sweeter than ever, IT WONT REV! As soon as it gets to 5k it misfires like mad. As mentioned the only thing we have changed is the end can, sprocket, new plugs and oil. Before it ran perfect now its just a mess!

Ive taken it to a local garage to try and sort out, theyve stripped the carbs, re jetted to try and improve the problem but nothing changes. Im being told its the front 2 cylinders that misfire once it gets to 5k.

So we know what the problem is, but whats causing it?!

He's told me to try and get hold of a different CDI, while im getting a new one, is it worth me gettin the ignitech CDI on my pretty standard NC30? Could this be the problem?

Any suggestions, help would be pretty appreciated!

P.S This is how the bike was looking once we put it back together..

[Andy666]

Do a search for 'limp home mode'. IIRC, if the bike doesn't recognise a speedo, it shows your symptoms.

Hope that helps.

[Tom1]

I think your right! Read a few off the search sounds exactly my problem. Im mad in a way, spent £250 with a garage who couldnt solve the problem, now its at the new place which im sure will charge me a nice bill! All for connecting one wire to a 12v source....nice!

Thank you Andy!

[Andy666]

No worries, glad to help. Now get that bike back asap before they can charge you any more

Nice bike by the way, hope you can get some time in on it before the weather turns

[Tom1]

Haha i know, im gonna get them to dyno it while its there, get it runnin bang on.

Thanks anyway, i know its not to some peoples tastes on here, a lot prefer to see original but each to their own. Lets hope it doesnt snow later this month!

Thanks again ill let you know how it goes.

[Neosophist]

I think your right! Read a few off the search sounds exactly my problem. Im mad in a way, spent £250 with a garage who couldnt solve the problem, now its at the new place which im sure will charge me a nice bill! All for connecting one wire to a 12v source....nice!

Thank you Andy!

250!

anyone with any basic knowledge of these bikes know that if the speedo sensor is disconnected or broken (plugs in behind the clocks) bike will missfire over 5500rpm.

I'd demand your money back!

Can be sorted in 5 minutes

[Tom1]

Well the mechanic that worked on it said that he used to have one! They are robbing ******** tried to charge me £80 for 4 spark plugs! I wasnt having that. They sorted an oil leak out, balanced and cleaned the carbs and put 4 new plugs in, 4 hours labour apparently...

[Neosophist]

Oh I see. I thought that was just to tell you that the bike is broken.

Strip and clean carbs might take two or 3 hours if you include balancing and re-assembling.

Plugs should be around 40gbp a set.

Invest in morgan carbtube.. 60gbp and you can balance the carbs whenever!

When you get the bike back theres a plug that comes from the speedo, this is the speedo-sensor.. make sure its' plugged in and the wires have continuity (connection) back to the ignition box.

[Tom1]

I have a koso speedo fitted to the bike, will it still apply?
And will i need to buy the 'plug and play' box from rick to de-restrict the top end speed now i have different speedo?

Thanks for the advice..

[marti]

If youve still got the original speedo just take the chip out and tape it up and plug it back in