Help, mechanical gurus

[eyefish123]

I have a 2015 660 Pro. Carl's 660 kit and clutching. Rode today and sled will not get close to max RPM. Running at 5500 RPM and pin the throttle and sled just dies and bogs at about 6400 RPM. Can ease into throttle up to about 7000 RPM and pin it and falls right back down to 6400 RPM and just sputters and backfires. Power valves were just cleaned. Is this a TPS issue? Thanks guys. I know there is a lot of knowledge out there and would like to take advantage of it before next weekend since our snow is going fast.
Thanks Again

 

[sled_guy]

Has it been running ok and just started this?

You say the valves were just cleaned, check them again and make sure they are sealing up and actually working.

sled_guy

 

[eyefish123]

Sled has been working well until the last few weekends where I have noticed a loss in rpm. Had clutch balanced and tried weight and spring change with little help. Noticed throttle cable has no play so will fix that. Also disconnected tether. Problem gets worse later in the day.