XJ900 (1FX) float levels - Has my manual got it wrong?

Since installing the new motor in my XJ900 I have been playing around with the carbies in an effort to get the mixture right.
More details of this can be found here-
http://www.xjbikes.com/Forums/viewtopic ... art=0.html

Recently I have increased the main jet size from 107.5 to 110 and lowered the jet needle clip one position but I still think it seems to be a bit lean at cruising speed. After doing much research I have started to think that my float levels may be the problem which brings me to the title of this thread.

All the info that I have seen in Chacal's posts list the float bowl fuel levels as being 5mm +/- 1. This is the same as the genuine paper Yamaha manual that I have which lists the following models - 1FW,58N,58L. It does not list the 1FX model which is what my engine is.

However I also have an electronic manual that says the fuel level for the XJ900N 1FX should be between 2 and 4mm.
Does anyone know if that is correct? :?:
If that is correct my current float levels would be too low as I set them at 5mm.
And if so why is this different to every other XJ900 model?
Before I pull my carbies out again to change the levels I was hoping someone might be able to confirm if the float levels for the 1FX are actually different.

 

Re: XJ900 float levels - Has my manual got it wrong?

I'm wondering why you're changing the main jet from standard? Are you doing stuff with the air filter to cause this lean running? Not sure why the 1FX model is different but I would go as per the electronic manual...

 

Re: XJ900 float levels - Has my manual got it wrong?

Because with the 4 into 1 exhaust system that is on my bike it seemed to running lean. I noticed that when I took the old motor out the BS35 carbies on it had a much larger main jet than standard which I can only assume had been set up for that exhaust system. Chacal didn't seem to think I should need to upsize it just for the different exhaust but I wouldn't know for sure until I tried it. But now I am thinking of putting the stock jets back in and raising the fuel level as per the manual as long as the manual is correct.

 

Re: XJ900 float levels - Has my manual got it wrong?

I thought that lowering the needle leaned out the mixture and raising it made it richer ?????,
cheers , Murray

 

Re: XJ900 float levels - Has my manual got it wrong?

That is correct.
I lowered the jet needle clip one notch which in turn raises the needle and makes it a bit richer.

As for the float/fuel bowl level maybe I will just have to change it as per the manual for the 1FX to see what happens as it seems no-one else has encountered this before. :?: It just seems strange that it would be different to all the other models.