Poorly NSR

**Mon Sep 12, 2011 10:01 am » Post: #1 » Download Post**

Rode my bike into work this morning and it feels completely different to when I rode it home from work the night before.

The powerband seems to kick in a bit later (around 9krpm instead of 8krpm), it has the slightest bit of resistance just before hitting the powerband and also seems to stutter slightly when releasing the throttle (the revs don't drop smoothly or quickly like they used to).

I have no idea what has happened overnight for this to happen. Has anyone else experienced this before?
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1996 MC28SE (Honda Flash), 24,000KM - Drilled airbox, HARC Pro pipes, TYGA Hi-flo reeds, special manifolds, Ohlins rear shock & steering damper - SOLD

1993 MC21SP (Winner's One), 10,000KM - Drilled airbox, wire splice - STOLEN!!!

1990 MC21SP (Cabin), 20,000KM - NC30 forks, discs, calipers - EN ROUTE...

**Mon Sep 12, 2011 9:13 pm » Post: #2 » Download Post**

Rev's not dropping tends to be a an air leak somewhere.
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Please do not PM me technical questions, if you can't find it on the Forum start a thread

**Tue Sep 13, 2011 8:01 am » Post: #3 » Download Post**

Did you refill the fuel tank the night you rode home?

Dirt in the tank may have partially blocked the fuel filter, which may mean the carbs are not filling quickly enough, which can result in lean running...
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball

**Tue Sep 13, 2011 8:05 am » Post: #4 » Download Post**

It does sound like something is causing it to run lean. Be careful! Possibly a blocked jet? Are you running a good fuel filter? The nylon mesh in the petcock does not offer much filtration.
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MC21 Honda NSR250. TYGA 300 conversion.

**Tue Sep 13, 2011 8:44 am » Post: #5 » Download Post**

Thank you gents.

I'll check the fuel filter on the weekend. I did fill the tank the day before the problem started so that must be it.

The bike had been sitting idle for a few months before and I replaced and cleaned the carbs, however I never checked the fuel filter.

**Tue Sep 13, 2011 12:00 pm » Post: #6 » Download Post**

Aha!

Might be corrosion in the tank from being stood so long, so have a good look in there with a bright torch.
_________________
MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball

**Wed Sep 14, 2011 7:21 am » Post: #7 » Download Post**

Dave Ett wrote:Aha!

Might be corrosion in the tank from being stood so long, so have a good look in there with a bright torch.

An Intrinsically safe torch if possible.