Hi Kev, I'm experimenting with your mods (O2 + fuel mod) which I installed a few days ago. I have a stage1 DNA air filter + removed snorkel (which corresponds to stage2 totally as far as I understand). And having great fun btw!

Air temperature is cold those days ( 6 to 8 degrees celsius).
I'm fiddling with the knob in the 4 to 6 o'clock range.

So far I experience:
- different sound (due to snorkel removal) with lotsa more low frequency rambling
- seemingly more power in the mid range (3500 to 6000 rpm)
- different kind of vibrations, somewhat "more rounded"
- very little less on-off effect, but so little improvement I could be wrong here

Past 6 o'clock A/F ratio seems to be too rich, but that's only an impression I can't further demonstrate.

Surging is still there where it used to be: a bit better in the low gears maybe, but absolutely unchanged from 3rd to 5th gear. Engine still thumps violently when giving full throttle under 3000rpm, just as it did before. I expected this to be smoothed out, am I missing something?

[QUOTE=Chenko;195306]Hi Kev, I'm experimenting with your mods (O2 + fuel mod) which I installed a few days ago. I have a stage1 DNA air filter + removed snorkel (which corresponds to stage2 totally as far as I understand). And having great fun btw!

Air temperature is cold those days ( 6 to 8 degrees celsius).
I'm fiddling with the knob in the 4 to 6 o'clock range. That is about right. It is quite hard to actually feel 0.8:1 A/F ratio this is the max the fuel mod can adjust, I have built the mod this way because of riders over fuelling their bikes & causing other problems with a t00 rich mixture.

So far I experience:
- different sound (due to snorkel removal) with lotsa more low frequency rambling
- seemingly more power in the mid range (3500 to 6000 rpm)
- different kind of vibrations, somewhat "more rounded" The different engine load will make the bike feel different.
- very little less on-off effect, but so little improvement I could be wrong here

Past 6 o'clock A/F ratio seems to be too rich, it would be but that's only an impression I can't further demonstrate.

Surging is still there where it used to be: a bit better in the low gears maybe, but absolutely unchanged from 3rd to 5th gear. Engine still thumps violently when giving full throttle under 3000rpm, just as it did before. I expected this to be smoothed out, am I missing something?

The fuel mod corrects the A/F ratio from the hardware that has been fitted like your filters, if we don't correct the A/F ratio the motor runs on the lean side.

The O2 controller controls the A/F ratio when we are cruising or riding around at light throttle openings, you should be able to lug the motor around in a higher gear at lower RPMs with the O2 controller.

There are a few other things that make these bikes feel like they are surging & would be looking towards the below items to be checked.

1/ Worn rear sprocket dampening rubbers are biggest culprit, grab hold of the rear sprocket & move the sprocket back & forwards, there should be no free play at all, if there is free play it will affect the bike cruises causing drive line shunt making the bike feel like it is surging.

2/ incorrectly adjust chain too loose.

3/ stretched chain, lift the rear wheel off the ground & support the bike in the air, place you hand under the lower chain & lift it up to the swinging arm, now turn the wheel slowly if the chain forces your hand up & down your chain is stretched & will make the bike feel like it is surging.

Unfortunately, everything mentioned was already checked:
1) sprocket dampening rubbers are brand new (changed them with last servicing)
2+3) chain tension is regularly checked and it gets cleaned and lubed every 500 or so kms

It really IS an erogation issue.

I was expecting the two mods to solve the surging (as many stated in the forums they would) but they seem to not do that in my case.

I'm pretty sure I installed them correctly, but anyway I ask: would the bike start at all if I installed them incorrectly?
Perhaps it is an exhaust issue, being I use the stock one?

I really would like to get rid of the obnoxious thumps I get when I open throttle below 3000rpm. :-(

The mods will not get rid of the obnoxious thumps you need to block your AIS pipe, the surging that the O2 controller fixes is at part throttle when the bike is cruising at small throttle openings when the ECU is in the closed loop mapping. The Fuel mod corrects the A/F ratio for hardware that is fitted like stage 1,2,3 air filters or & pipes.

As everyone knows I offer a 100% money back on any of my mods, only one person has ever taken up the offer in 7years. You are very welcome to post the mods back top me tomorrow in the condition you received them in & I will refund you the money that you paid for them upon receipt of the mods.

No, I'm happy for the other achievements, I'm keeping your nice mods thanks! :icon_burnout[1]:
I'll get rid of the AIS then, back to the garage!! :-P

I am sure your problem is the AIS still connected & running with an open air box, let us know how you get on.

Blocking off your AIS

XTZ
http://www.xt660.com/showthread.php?...d=1#post101266

XTX & XTR
http://www.xt660.com/showthread.php?t=5544

Does blocking up the ais pipe reduce the hard thumps when using the throttle in a high gear?

I thought that this would only reduce back firing or popping?

I thought that too, and Italian T�n�r� owners in the forums seem to think the same, nonetheless I shall verify it first hand since Kev seems to know this engine better than anyone.

A question: to solve thumps below 3000rpm in high gears, could one just block with a wall stopper the air entrance on the side of the bike, or should the AIS be removed completely?

I am a little skeptical, As all the reports only seem to mention the popping. I was going to plug it up during the holidays but not sure now.

I have a tenere too. Does anyone know if it is essential to remove the tank to plug it up? I have nt removed it yet on the tenere but I've hated doing it on all my other bikes. That dreaded fiddly fuel line. I know I'm going to end up shouting at the fuel line .

I blocked the AIS on my Tenere , i ended up removing the tank as access is very tight .