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Discussion Starter #1
Already posted this on www.superduke.net but thought I'd try my luck here as well.

I just did the TPS check as my bike has been suffering from low idle problems.
- Cleaned the Throttle Bodies with limited improvements
- Throttle free play has been checked by the dealer
- Diagnostics did not show any issues
- side stand switch cleaned and checked

My next step was to check the Throttle Position Sensors (TPS)
According to the manual they should be set at:
Front: 0.6v (closed throttle) - 3.8v (open throttle)
Rear: 1.0v (closed throttle) - 4.3v (open throttle)

When I checked I found that the front TPS (black connector) was showing 0.75v at closed throttle & 3.66v at full open.
Made some adjustments and the front TPS (black connector) was showing 0.64v at closed throttle & 3.51v at full open.

Did the 15min idle and she sits and idles fine.

After the 15min ECU reset I started the bike up again and she went up to 3000rpm, before dropping back down to 1500rpm. When I run the engine and I hold the revs at say a steady 3000rpm all seems OK but when i increase the throttle at 3500 or 4000rpm the revs start to 'bounce' up and down. (~500rpm up/down)

Went for a short test ride and the symptoms are the same plus it doesn't drop the revs below 3000rpm when I close the throttle in gear.
So went back to the house.

Why is it that when the TPS is within the parameters I still have this problem.

The rear was spot on at the first reading but now I do not get a open throttle reading (both 2nd valves do respond to throttle openings) -
Rear TPS at closed throttle is now 0.98 - no open reading.
Front TPS at closed throttle is now 0.64 - open reading 3.51v.

Any ideas?
 

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Did you make sure you made the readings with a hot engine?
Closed to be measured with engine running - open with engine NOT running.
 

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Discussion Starter #3
Made some more adjustments and with seemingly good results. (thanks for the reminder Pete.)
The bike is now running much better over the rev rang. I did not come across anymore revs bouncing up-down at 3500rpm.
(I replaced the battery as well and sprayed the BGC with plenty GT7 which I had in the shed. But I am pretty sure that the TPS adjustments were what made the difference.)

Needless to say I was delighted with the result so far and I put the bike back together. I wanted to take one last reading before closing the RH side panel on the airbox and going for a test drive. At that moment the fuel line burst at the point where it connects to the fuel tank!! The pressure in the tank must be quite high as it was spraying petrol all over the running bike. (My wife and 9 month old son were standing just 4 feet away) As quick as I could I switched off the bike and thankfully nothing happend.

On one hand it's bad luck - fix one thing/break another. But I am very glad it happend now rather then while test riding the bike!!!
Will have to order a new fuel line before I can finally find out whether the bike is now running as she should.

Will confirm back if the problems are now fixed pending fuel line replacement.
 
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