Limp home mode?

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lizard821000
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Re: Limp home mode?

Post by lizard821000 »

does it happen all time mate? or just once warmed up?
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bikemonkey
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Re: Limp home mode?

Post by bikemonkey »

All the time, although I don't like revving it above 6k before the gauge hits 70
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CMSMJ1
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Re: Limp home mode?

Post by CMSMJ1 »

it has a 33bhp restriction too? This revving is all on the stand is it? Or ridiing it?
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bikemonkey
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Re: Limp home mode?

Post by bikemonkey »

Yeah, just to clarify everything:

33bhp restriction washers
Not re-jetted to suit (yet)
Acumen tempest cat 1 alarm and immobiliser
Standard CDI

Before my crash the bike revved and ran fine through all gears to about 10k then it didn't seem to want to go anymore which I'm guessing is the washers.

The current problem is the bike revs up to 10k fine in first (this is all whilst riding), then again in second, gets to about 8k in third and bogs me right down to 5.5k (feels like misfiring, power delivery jerky) then up to 4th 5th 6th wont let me rev above 5.5k with the same jerky delivery.

This happened with the speedo plugged in and disconnected.

As I said I'm going to do the resistor mod, and if that doesn't work then I'll have to think a bit harder.....
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Cammo
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Re: Limp home mode?

Post by Cammo »

Have you checked the simple things like battery connections, earths etc? It sounds like a connection might have come loose in the crash.
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magg
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Re: Limp home mode?

Post by magg »

The speedo rpm limiter does not know which gear is selected therefore when disconnected the rpm should be limited to approx 5500 in all gears and neutral. In neutral it should start to run rough at 5500 rpm and struggle to get much above. Your problem does not sound like the classic speedo limiter issue. How exactly did you crash?
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bikemonkey
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Re: Limp home mode?

Post by bikemonkey »

It was a lowside round a right hand bend, straight onto a grass verge.

I had crash bungs attached and they did their job well, the only things that were damaged were 3 panels, the screen and screen brace, the right front light unit and the crash bungs themselves.

I haven't checked earths and battery connections etc but I will, although everything else on the bike works fine, starts on the button everytime etc.
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Re: Limp home mode?

Post by magg »

Might be fuel starvation. Have you checked the fuel tap vacuum hose and flow from the tap. Might have been damaged or pulled the hose when you came off and only shows up on longer periods of high rpm.
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Re: Limp home mode?

Post by Neosophist »

It shouldn't rev past 5.5k in any gear (there isn't a gear sensor on the NC30) so the restriction affects all gears.

It sounds like the wiring loom has already been modded somewhere (or maybe ignition box has been modded)

Is the vaccumn pipe ok? It can often collapse as speed builds up and cut the fuel off which causes the shitty running.
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bikemonkey
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Re: Limp home mode?

Post by bikemonkey »

Well it sounds like the wiring is modded somewhere then because even with the speedo unplugged it let me rev past 5.5k.

The CDI is standard used unit from geoff, and I have an alarm fitted, can post up the wiring diagram of it if needed.

Where could the wiring be modded other than the CDI?

Just off to check the vacuum hose and electric/earth connections, shall post back soon....

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