nc30 rough idle when hot

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krisztian_andre
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Bike owned: MG v35 II, NC30, MG NF Mil.
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nc30 rough idle when hot

Post by krisztian_andre » Tue Mar 22, 2011 9:18 pm

The engine idles nicely until it heats up to the point that the fan starts, once that happens I have to adjust the idle speed up to 2k rpm or it would stall and the meter falls to 1k rpm around every 2 seconds as if it missed a few firings. Otherwise it does not lose power noticeably when hot. Carbs are balanced, it's an engine with around 70 000 km and has been like this ever since I had it (around 10000km). Is this normal with this milage or is there something I can do about it?

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skinnydog0_0
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Re: nc30 rough idle when hot

Post by skinnydog0_0 » Tue Mar 22, 2011 9:52 pm

Possibly valve clearences?
Have you checked them lately?
An NC is for life, not just for Christmas!

krisztian_andre
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Joined: Fri Oct 02, 2009 6:49 pm
Bike owned: MG v35 II, NC30, MG NF Mil.
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Re: nc30 rough idle when hot

Post by krisztian_andre » Wed Mar 23, 2011 6:40 am

Have to double check that with the mechanic, I told them to but they probably thought "what for" and just skipped it. I'm also suspecting blowby because of oil in the airbox and it's eating around a liter of oil in high speed operation per 1000km. I did that thing when you keep it 5000rpm for 15 seconds or so and the rev it up suddenly and there is black smoke not white/greyish. Compression is uniform around 10 kg/cm2.

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CMSMJ1
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Re: nc30 rough idle when hot

Post by CMSMJ1 » Wed Mar 23, 2011 7:08 am

WHy is it sittingon idle when actually is that hot? I'd turn the bugger off!!

I get the feeling an HRC air try might help and shield the carbs from the high heat if you are in high ambient..

Valve clearances..lol - Any mechanic that said "Why?" needs to go and sell ice cream...
IMPERATOR REX ANGLORUM

The V4 is the law..

NC30 - No9 - my old mate

krisztian_andre
Familiar Member
Posts: 484
Joined: Fri Oct 02, 2009 6:49 pm
Bike owned: MG v35 II, NC30, MG NF Mil.
Location: Germany

Re: nc30 rough idle when hot

Post by krisztian_andre » Wed Mar 23, 2011 9:08 am

HRC air tray yes or I could make something out of insulator sheets, the ones used to insulate the fairing.
He didn't say that it's not needed I just suspect because of the valve covers looked undisturbed after the initial service.

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