NC30 wont rev cleanly past 5K RPM

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Sabre
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NC30 wont rev cleanly past 5K RPM

Post by Sabre »

Bought my VFR after it had been sittin up a few months very boggy and wouldnt go past 5K RPM.
Total oil/filter change with cleaned carbs and although it will revs out fully its still a little stumbly at 5K and i have to drop gears sometimes to pick up speed.
Any ideas whats wrong?
Def not dirt in the carbs

Cheers 8-)
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Sligeach
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Re: NC30 wont rev cleanly past 5K RPM

Post by Sligeach »

what makes you so sure its not dirt in the carbs?

did you totally empty out the tank after you cleaned the carbs? after a bike sits for a while water can seep in through the filler cap and into the tank, especially if left outside.

this watter can then makes it way to the carbs. also how through was the cleaning job you did?

and what was the condition of the carb rubbers and did you get them to sit right again?
wullvfr
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Re: NC30 wont rev cleanly past 5K RPM

Post by wullvfr »

+1 on what declan says...........

what exhaust system is on the bike also just out of curiosity,is it standard....aftermarket end can?????



william
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Jon
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Re: NC30 wont rev cleanly past 5K RPM

Post by Jon »

Is the original snorkel still in the front of the airbox?
Have you messed with the airbox lid in any way as they are sensitive to changes in the airbox/filter area?

They also have safety circuit built in that will make them run on 2 cylinders if the speedo and tacho are not connected.

regards
jon
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Sabre
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Re: NC30 wont rev cleanly past 5K RPM

Post by Sabre »

We used an entire can of carb cleaner and absolutley scrubbed them so they are def clean,my mate who is a big fat shit put them back on and they are well planted on the bike,carb rubbers are fine as are the seals (taken my CBR apart more than once sadly)
Could it be plugs?
Its really annoying!
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Sligeach
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Re: NC30 wont rev cleanly past 5K RPM

Post by Sligeach »

as jon says 5K RPM is significant as that's when the revs cut out if the speedo isn't attached, but if it will clear the 5K RPM eventualy its not speedo related.
did you take out all the pilot jets and everthing and use compressed air?
Sabre
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Re: NC30 wont rev cleanly past 5K RPM

Post by Sabre »

We took them all out but just used cleaner my mate had a compressor and ill take em out again and give that a try.
Some power outta the bike ruined by the jerkiness :-(
Thanks for all the replies!

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