Daz, i thought it only effected the tuning in closed loop around 10-20% throttle, between 2200-3800revs.

My bike is running alot smoother than it did before all mods, so I am very happy with that outcome.

Other than that, a great post..

Hmm I'm not sure about the revs though, here Dynojet says 3500 - 6000 rpm:

http://www.xt660.com/showpost.php?p=57374&postcount=16

But still it should only effect up to 20% tps.

Hi Naz, yep thats what Dynojet say, but I think it was Kev who found my information........

Aha ok, I see.

From all the dyno runs I have done with 5 different XT's the best HP & Torque was from A/F ratios between 13.2:1 below 4000rpm leaning out to around 13,5:1.

16:1 is way to lean & have never seen a motor produce it's best HP at that A/F ratio. I suspect your exhausts are not completely sealed or are leaking or the CO dyno meter was not deep enough in the exhaust. I will PM you my email address please email me your fuel map to have a look at, I will be able to see straight away it the A/F reading is out. The dyno tuner would have tuned for the best result, I just think the A/F reading are not correct.

Hi Kev...i did check for any leaks and used paste for all joints on my new exhaust. But I will double check them.

I agree Kev...looks like the AF's are up the creek!

But she runs sooooo sweeeeet!!!!! and doesn't pop by the way, and the low end power/ running at low throttle positions is excellent!!

I am sure it runs well & nothing really for you to worry about as the dyno would have told the operator where the best HP was.

Have a look at one of my dyno runs, look at the last graph, the A/F ratio is at 14.7:1 in Blue is to lean compared to the green line at 13.71:1 now run up the line you will see the blue line is down in Torque & HP. See how it lost HP & torque with a lean A/F ratio.

http://i201.photobucket.com/albums/a...tx/xt660-2.jpg

I am sure you are going to have a sore face, from all that smiling, now go enjoy that bike.
:ytiller:

and I have just double-checked carefully, no exhaust leaks.:bunny: