My last jetting question - 07 WR450

I am 95% there with my jetting. Finally... after much trial and error... no off idle bog, no sputtering, no backfiring. The bike runs strong, crisp and smooth through all gears UNTIL I am going faster than 50 mph. I am experiencing some sputtering at constant throttle and backfiring when i let off on the throttle. What factors would cause this?

Altitude: sea level

80-90F avg. Temp

GYTR fuel screw 1.5 turns out

R&D Power pump w/ ALJ set at 40

168 Main

45 Pilot

JD Red needle, clip in 4th position

DR D full race exhaust

All free mods done

Thanks

incorrect jetting.

I am 95% there with my jetting. Finally... after much trial and error... no off idle bog, no sputtering, no backfiring. The bike runs strong, crisp and smooth through all gears UNTIL I am going faster than 50 mph. I am experiencing some sputtering at constant throttle and backfiring when i let off on the throttle. What factors would cause this?

Altitude: sea level

80-90F avg. Temp

GYTR fuel screw 1.5 turns out

R&D Power pump w/ ALJ set at 40

168 Main

45 Pilot

JD Red needle, clip in 4th position

DR D full race exhaust

All free mods done

Thanks

Check this out. No resolution but some suggestions.

http://www.thumpertalk.com/forum/showthread.php?t=636373&highlight=stutter

I am 95% there with my jetting. Finally... after much trial and error... no off idle bog, no sputtering, no backfiring. The bike runs strong, crisp and smooth through all gears UNTIL I am going faster than 50 mph. I am experiencing some sputtering at constant throttle and backfiring when i let off on the throttle. What factors would cause this?

Altitude: sea level

80-90F avg. Temp

GYTR fuel screw 1.5 turns out

R&D Power pump w/ ALJ set at 40

168 Main

45 Pilot

JD Red needle, clip in 4th position

DR D full race exhaust

All free mods done

Thanks

when your doing 50mph i assume your only about 1/4 throttle and are in 5th gear right? two things....if it was me i would do a 48 pilot as 45 is stock and thats pretty lean and then i would check your throttle positioning sensor (TPS)...

incorrect jetting.

thanks smart arse.

Did you take off the AIS? That was causing backfire on decel for me. Removed it and have not heard a pop since.

Yes AIS removed. I will look into disconnecting the TPS and report back what i think.

I disconnected the TPS at the 3 pin connector under the tank and taped it up. Ran the bike and guess what... Problem Solved... I did not notice any loss in power either (mentioned in the manual and some TT members experienced this). Thanx for all the help.

I was going to tell you to fiddle with the TPS, but it appears you already have... I sure would like to know the other effects of disconnecting it.

I have heard you should keep it plugged in for off-road, but I cannot remember why. I ride about 95% off-road, but the 5% on-road can be annoying due to the "TPS Stutter" Please keep us posted.

Thanks.

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