NC35 Racebike Carbie Issue - fuel in bowl, not in cylinder

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Suzuki416
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Bike owned: 3 x NC35, 2x NC24, NC29, RC46
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Re: NC35 Racebike Carbie Issue - fuel in bowl, not in cylinder

Post by Suzuki416 » Fri Jan 04, 2019 10:56 am

Rohin,

I just want to check what I'm reading - you don't think the bike is running on 4 cylinders, yet will rev to 12,000 unloaded... I'd suggest the mains are working fine - lol

I'll assume you guessed the misfiring cylinder was number 2 by the temp of the exhaust pipes?

I'd look at your idle jets on all the carbs & absolutely re-synch them..

RoninZX-10R
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Re: NC35 Racebike Carbie Issue - fuel in bowl, not in cylinder

Post by RoninZX-10R » Sun Jan 06, 2019 7:59 pm

Hi Suzuki416, yeah that's exactly right. When it's idling, and revving it a little to warm up the engine, it'll only run on 3 cylinders, number 2 won't fire for some reason (confirmed only from the temperature of the header pipe). I had the bike on a dyno yesterday and it ran fine all the way up to redline, so my guess is it's out of balance. I've borrowed a mates carbie sync tool so I'll have a look at that in the next couple of days.

I'm assuming when I sent my carbies out to get ultrasonically cleaned and set up for racing that they may have accidently turned the synchronising screw. I'll report back in a few days...fingers crossed I'll have it sorted quickly!

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gavins
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Re: NC35 Racebike Carbie Issue - fuel in bowl, not in cylinder

Post by gavins » Tue Jan 08, 2019 1:51 pm

Have you checked the float height as well? Have had similar issues with one cylinder not firing until it's warmed up and revved out - turned out to be the spark plug in my case.

RoninZX-10R
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Re: NC35 Racebike Carbie Issue - fuel in bowl, not in cylinder

Post by RoninZX-10R » Wed Jan 09, 2019 11:25 pm

Hi Gavins, yeah the float heights have been all checked and adjusted. I've swapped the spark plugs to other ones, but that didn't make a change, so I'm hoping it's the carbies being out of balance. Haven't had a chance to get onto it yet unfortunately.


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