engine diagnosis

[simonm]

Hiya all.  A friend of mine is having a problem with his fazer and I was wondering if anyone could diagnose the issue from the evidence I have ?

Cheers

Issue: above 6,000 rpm loss of power engine sounds like it is misfiring/rough

Tried
: coils swapped with known good
: TPS swapped with known good
: plugs swapped with known good
: ignition unit swapped with known good
: breather tubes checked
: reg/rec swapped with known good
: all electrical cables checked for corrosion

Apparently the carbs have been balanced recently although I understood that normally affected low revs..

To all intents and purposes the electrical system seems fine.  The brakes, lights, cooling system, clutch and gears work too.

Any ideas please ?

[Dead Eye]

Have you checked the air inlet and filter as well as the fuel filter?

[BBROWN1664]

TPS swapped, but was it set up?

Does it have a restrictor kit fitted?

[positron]

I recently when thru something similar, and it turned out to be a clogged up air filter. Here's the thread with some solid sensible advice from Unfazed and others here.

http://foc-u.co.uk/index.php/topic,13563.0.html

[simonm]

Tps went to 10,000rpm and rotated back until it went to 5000 rpm and tightened.

[simonm]

Air inlet unblocked and air filter clean.  I'm assured the fuel filter is clean/new but that's a wildcard atm..

[simonm]

No restrictor kit AFAIK. The bloke doesn't think there is a restrictor fitted .

[chaz]

a mate bought a cagiva the one with the tl 1000 engine, it was only just run in when he got it, it wouldn't rev over a certain range, he was a mechanic and had checked all electrics etc, we thought it might be a broken valve spring?
It turned out to be a MISSING valve spring which had never been in. You just never know.