06 M7 Top End Bog

[M8 Rider]

We went riding at Strawberry today with WAO. We have run into a top end bog that is intermitant. His 06 M7 runs great at 1/2 throttle or less some of the time. When it acts up it feels like a rev-limitter kicks in. No check engine light or codes seem to be present. We have checked the power valves and wiring the best we can. The only modifications that have been done are HPS can,Speedwerks sigle pipe,and .010 milled cylinder head. HPS can has been on since new and cylinder head\pipe were done this season. Any suggestions? Thank you for your help!

 

[drosichu]

Some of the M7's do not like aftermarket cans so try putting the stocker back on and check your clutching. If your buddy normally rides at different elevations you might need to adjust his primary weights

 

[W A O]

06 m7

Some of the M7's do not like aftermarket cans so try putting the stocker back on and check your clutching. If your buddy normally rides at different elevations you might need to adjust his primary weights

This sled has never had a stock can on it and for three years it has run great
This started last week an it ran great for about 2 1/2 3 hours,RPMs on a good climb would hold good at 7950-7980. And then it fell flat on its face so we took it home.


We cleaned the powwer valves same we put the stock pipe back on and nothing,then we thought about the tail light short so we diconected the tail light leads and it started to be intermittent,about every third time you pin it it runs great or very close but the other times it will go to 7100-7200 RPMs and then fall back to 6200 or so.
Could this be an electrical problem and if so where to start, ran all day yesterday with no hand warmers or thumb and lights on low beam( i think) and no tail lights so what? any info would help we are trying to look at this with an open mind. thanks for your help

WAO