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Discussion Starter · #1 ·
Hello from Belgium.., i have a tornado tre 900 in the workshop with a disappointing trouble..

When engine running at 3000 RPM for about 20..30 sec, with no load, the central exhaust tube is turning red at the output of the head..

This tube is badly rusted while the others are fine, this is why the owner came with it..
I think the exhaust valves don't appriciate this treatment.
The engine is running fine otherwise..

Does Anybody met the same trouble or can advise, as it is the first time i work on a tornado tre

Discussion Starter · #3 ·

I suspect a valve clearance to small on exhaust valve for the inner cylinder..

I will check tomorrow..

Discussion Starter · #4 ·
red header pipe

It is throttle body synchronization, the middle cyl is running leaner because that throttle butterfly is open further. Because the injectors release the same amount of fuel for all cylinders, if one butterfly is open further letting in more air, it will run leaner and hence hotter.

I have adviced a few forum'ers of this, this is a quick way to tell if the throttle bodies need sychronization, run the bike at night and see if one or two of the exhaust headers glow more red than the others.

I have tested this many times, I have always found the cylinder with the red header to have less vacuum on the gauges showing that that throttle plate is open further.

Discussion Starter · #6 ·
Re: red header pipe

I've made some work on this bike..
Here is the sumary of my experimentations.

Valve clearance were not bad, just exhaust valves on the center cylinder 0.1mm too large..
As i suspected clearance too small on exhaust, this is definitely not the reason of the trouble !!

Synchro as suggested by Johnny O is quite different..
I've discovered there are several ways to synchronise on this engine due to the idle stepper..

I tested before adjusting, and surprinsingly the center cylinder was sucking really more HG vacuum then the 2 others..
damned, just the opposite of Johnny O explanation..

I decided to work the following way :
I disconnected the 3 tubes coming from the idlling stepper, taking vaccum on the throttle body and synchronised the 3 plates perfectly..

Then i connected the 3 tubes (with Y and vacuum meter), with screw bypass closed, and synchro were off !!
I assume that there is a different pressure loss in the tree conections, y tried to correct the synchro by tuning the small airscrew, but couldn't achieve correct result.
I've been obliged to adjust one of the throttle plate slightly to be OK on 3 HG.

The 2 ways are :
- mechanical synchro OK, but total synchro out because difference induced by the stepper
- mechanical synchro out, but corrected by the difference induced from the stepper..

I choose the second, as it seems to me that is what the engine really pumps.
Workshop manual is quite poor about this..
We'll see once everything will be on and bike on the road..

Discussion Starter · #7 ·
Re: red header pipe

Very interesting, do you realise that if you moved the right hand butterfly during sync that the throttle position sensor may need reset by axone or tuneboy ?

Discussion Starter · #8 ·
Re: red header pipe

Yes, but i don't know how "sensitiv" is the TPS reset.

You have the RPM range divided in different "step",, and 1 or 2 degrees moved for TPS shouldn't make a step increase (I hope).
On bike like guzzi you offset on purpose to fool the ECU and increase fuel delivery a little.

Anyway you have no choice with those injected engines..

Discussion Starter · #9 ·
Re: red header pipe

Please let us know how it goes when you have it back on the road.
I have a run fault with mine,that the supplier can not sort out!
I have therefore been trying to find out about setting of the throttles.
I have been on the triumph forum ( and the way that I understand they set them is by the butterflys with the stepper tubes removed. It seems they dont worry if the sync is out a bit when the stepper is connected. If set as you did which is the way benelli say in manual, I would assume that when you open the throttle slightly the syn must then go out ? .
If some sort of valve were fitted in the stepper pipes you could set sync of butterflys, then reconect the stepper pipes and re sync with the valves in stepper pipes, then it should be perfect ?
One other thing I got from the triumph site is the stepper pipes could be blocked, or split, both of which would cause the sync to go out ?
did you have to remove the upper side fairings to adjust the throttles ?
sorry to ramble on, colin.

Discussion Starter · #10 ·

There is only one way to correctly synch the throttle plates, and that is with the stepper disconnected. I screw main jets into the vacuum lines to give the engine enough air to run.

I also set the bi-pass screws at 1 turn out at the minimum, I tend to find that it eliminates the off-idle lurch that fuel injected bikes tend to suffer from.

With the throttle plates synch'd properly, I can get the engine to tick-over smoothly as low as 700 rpm!

Discussion Starter · #13 ·
Re: synch

Answer to colin : to proceed you have to remove not only top fairing with ducts, but also tank and airbox (sync screws are underneath), and continue to feed with fuel..

I definitely love ducati pivoting tank...

I had checked stepper internal for free flowing..

For Johnny O : i totally agree with you, and that's the way i've synchro all bikes till now (see my blog attached with profile), but this one drives me (a little) crazy..
Anyway, without experiment on this engine, i will thrust you and rework "mechanical" synchro.. (bike still connected to vacmeter in the workshop)...

Discussion Starter · #14 ·
Re: synch

Well here is the results of the work..

The synchro must be ok now, as i have all 3 exhaust pipes turning red when revved 3000 RPM for 15..20 sec with no gear..
Difficult to check on the road because of rain for the 2 previous days..

So i assume that's the way the engine is mapped (ignition/fuel) at this running point by the factory..
I hope this alpha/N combination doesn't occur while riding..

Can somebody confirm that fact on other bikes..
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