Grumpy Trumpy

[stiple]

Hi all,

I'm new to this awesome site and I'm hoping that beginners luck coupled with some good brains may help me with a really annoying issue i have with my 97 T509.

the symptoms are:

Burbling Idle - its just doesn't sound right, pops and sounds spluttery.

small throttle openings upon Accelerating and decelerating sound like its missing making it jolty in traffic, very annoying... when slowing down in gear (engine braking) it sounds normal until about 2k rpm's at which point it pops, surges forward and begins to stutter as mentioned above, occasionally it back fires near the 3k rpm's mark especially if you have a small throttle opening during the engine braking towards a corner following a few back fires it becomes sluggish in response.

Hesitant throttle when 'blipping'

Full open throttle openings - when opening the throttle wide open in 6th at low revs or under similar 'hard' working situations, it splutters, stumbles, pops and bangs and as soon as its past 3-4k rpm's its off like a rocket!

OK so i tried..

New Inlet manifold gasket.
New stepper motor.
New Vacuum pipes to the stepper (IACV) assembly.
New Crank Sensor, correctly adjusted.
New plugs.
new temp sensor.
Checked Coil packs, all read the same ohms, all have the same dwell reading whilst running.
Checked Valve clearances. - all spot on.
Throttle body sync 4 or 5 times!
Co level adjusted to the book, then up and down 1% using a gas analyser. - no changes, just gets richer.
tried multiple ECU engine maps using Tuneboy.
Checked Airbox for cracks and holes, and that all pipes are snug.
Checked each engine/speed sensor, ohms and for deterioration.
cleaned injectors
changed fuel filter, checked tank internal fuel pipes for tight connections.
cleaned one way ball valves located in the vacuum tubes.
Ran fuel system cleaner
checked exhaust joints.

Always use the best fuel I can get

Oh and the Plugs are the correct colour!

But still... the problem exists..........

Am i just missing somthing simple here? these bikes can't run like this from the factory???!

Its got to be something to do with the low speed running system, but I'm stumped.. interestingly the bike idles when the throttle body sync gauge is connected, should't it stall?? thats my only clue..!

Any ideas?

cheers in advance for any help with this deeply disturbing issue..

[denny]

Compression test?

[stiple]

Cheers Denny,

Forgot to mention that I had checked that too, got good readings..

thanks for the thought though.

[cave1]

What exhaust and what number Triumph map? I had some of your symptoms running the stock pipe with an older (1999 issue) dealer-installed map. So with the Tuneboy, did you switch between the latest available Triumph maps: 9852, 9853, 9854? There just don't seem to be a lot of custom tunes out there for the T509...

[OKcarburetor]

leaky injector?