NC30 dyno 45hp :(

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krisztian_andre
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Re: NC30 dyno 45hp :(

Post by krisztian_andre » Thu Jun 14, 2012 1:38 am

lizard821000 wrote:stop posting and get to some bars, mama sans for sale.
I don't bother the bars and they don't bother me.

marti
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Re: NC30 dyno 45hp :(

Post by marti » Thu Jun 14, 2012 11:25 pm

I had an nc 30 that made 45hp on a dyno and it was traced to a bent inlet valve on 1 cylinder.
I would guess you have a similar problem, 1 weak cylinder

krisztian_andre
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Re: NC30 dyno 45hp :(

Post by krisztian_andre » Fri Jun 15, 2012 12:30 pm

marti wrote:I had an nc 30 that made 45hp on a dyno and it was traced to a bent inlet valve on 1 cylinder.
I would guess you have a similar problem, 1 weak cylinder
I see. Going back to dyno shop to get my a/f ratio graph and after that it's valve clearance, ignition diagnostic and carb setup. How did you find out about the bent valve?

Neosophist
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Re: NC30 dyno 45hp :(

Post by Neosophist » Fri Jun 15, 2012 1:16 pm

krisztian_andre wrote:
marti wrote:I had an nc 30 that made 45hp on a dyno and it was traced to a bent inlet valve on 1 cylinder.
I would guess you have a similar problem, 1 weak cylinder
I see. Going back to dyno shop to get my a/f ratio graph and after that it's valve clearance, ignition diagnostic and carb setup. How did you find out about the bent valve?
Neosophist wrote:After you've set the valve clearances and compression tested it you'll know if it's worn inside / valve are leaking.
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...

krisztian_andre
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Re: NC30 dyno 45hp :(

Post by krisztian_andre » Wed Jun 20, 2012 4:20 am

I got the a/f graph and it looks like a mountain range.

Image

krisztian_andre
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Re: NC30 dyno 45hp :(

Post by krisztian_andre » Wed Jun 20, 2012 6:07 am

The power curves were identical between the two runs with the major peaks and valleys corresponding. what I'm saying is that the variations doesn't seem to be random. Can someone show me a close to ideal a/f curve for a bog standard jap spec NC30?

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CMSMJ1
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Re: NC30 dyno 45hp :(

Post by CMSMJ1 » Wed Jun 20, 2012 7:44 am

Your bike is running far too rich - get some smaller jets in it for starters.
IMPERATOR REX ANGLORUM

The V4 is the law..

NC30 - No9 - my old mate

krisztian_andre
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Re: NC30 dyno 45hp :(

Post by krisztian_andre » Wed Jun 20, 2012 9:21 am

Question is, why is it so rich when all it's components from the exhaust to airbox and jets are standard? Can it be carbon deposits on the valves or a clogged exhaust? Carbs are clean btw.

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CMSMJ1
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Re: NC30 dyno 45hp :(

Post by CMSMJ1 » Wed Jun 20, 2012 3:54 pm

It can be rich due to atmospheric conditions. What altitude do you live at? What is the fuel quality?

There is no doubt it is far too rich. So, you make it leaner..which will make it more powerful, more efficient, cheaper on fuel and stop killing plugs...
IMPERATOR REX ANGLORUM

The V4 is the law..

NC30 - No9 - my old mate

krisztian_andre
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Re: NC30 dyno 45hp :(

Post by krisztian_andre » Thu Jun 21, 2012 8:46 am

I at sea level high humidity, 34 C temperature. It has 115 118 jets now, what size and brand of jets should I get?

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