Gems leaning???

[powder muncher]

I had my Apex stage 1 High boost setting lean out for no reason, burned 1/2 a tank of gas and was right on 12 to 1 wide open . Then all of a sudden it jumped to 13.5 to 13 .8 to one and even gave a lean pop.

Had to bump up bumped up altitude and started to bog.

Reset altitude back and added .5 on main jet and boost adder-- all was good again.

Easy to adjust but why would it move any one have insight into this or dealt with this before ?

Thanks.........

 

[yooper1]

Was there a temp change? I am right on at about 10 to 25 and warmer and I am fat.

 

[347strokin]

Was there a temp change? I am right on at about 10 to 25 and warmer and I am fat.

Or decrease in altitude?

 

[powder muncher]

No big changes at all, I ride the same area lots and never have to adjust it there, is all between 3000 and 4500 feet and temps were within a few degrees all afternoon. Once in a while if the temp drops a lot on the way down the fuel numbers go up to 12.5 - 12.75 to one WOT from 12 to 1
The lean out happened right on top at 4500 feet.

Almost wonder if I should keep a spar gems box?

Checked all connections ground the works all is A-OK.

I have about 500 km on the super by now is there a change in the blower as it wears in ?? friction drive working more efficient or so??

Thanks........

 

[quebecmoutainrider]

my gems did the samething..screwing up that is...it showed no boost for most of the ride..but it was still working..then when it did work it showed 17psi...nooo...but the next day after being in the garage heated..it was fine..could just be reading bad..have not had that problem since then..and by the way...the oxygen sensor will only last 1500 or less..had one for 1800 once..but they usually burn around 1000 k..might be that going..

 

[powder muncher]

Did the re calibrate on the O2 and it was right on.

It also lean poped so it all makes sense from that point.

I guess Just wait and see for the next ride and pay att on hard pulls.