Yamaha TRX850 Enthusiasts Forum

went for a ride out today and at 100ks an hour which is 3000rpm it seems to stutter, if you give it a hand full it clears then 5 mins later it does it again, its almost like a two stroke just before you hit the power band stuttering,is it anything to worry about as where going on a big ride out at the end off the week for 3 days any help or advice would be much appreciated ,Steve

Kiaora Foggy, 3000rpm is too low for 100kmh. Chuck it down 1 or 2 gears and keep it boiling. Mine doesn't like top gear anything under 3500rpm (17-42 combo).

Hey bro
Me thinks you need new needle jets (emulsion tubes)eh bro. Go for your run and give it the berry's eh.
Common problem old chum. Tubes oval out stuffing up your fueling on a steady throttle,feels like its running out of fuel.

Good luck and enjoy "Giving it the berrys":twisted:

Cheers, Al (Ex Southlander)

thanks for the replys, looks like im going to have to strip the carbs come the winter then but for now il just keep giving it the berries

Kevtrx849 wrote:Kiaora Foggy, 3000rpm is too low for 100kmh. Chuck it down 1 or 2 gears and keep it boiling. Mine doesn't like top gear anything under 3500rpm (17-42 combo).

...................so I guess yours needs looking at too then

Really, i thought my flatslides were in pretty good shape. I run 17/42 combo and 100kph equates to about 3800 rpm, anything slower in top and it starts to lug and chug. Maybe my Over cdi is the cause but If rejetting works for you then go for it.

IMO the valve timing is pretty mild on these engines and stuttering at 3000 rpm (whether with flatslides or CV carbs shouldn't be happening. I've had a bit of experience setting up standard carb versions of these motors (different induction, jet kits and exhausts - 2:1 systems are a pig to setup) and they generally pull well from 2500 rpm and get into their stride around 4500rpm

Hmmm I have to agree,3000 rpm seems pretty sweet on my TRX and I`m running stock gearing with FCR41`s.

Maybe our thin heated oxygen is to blame. In the winter with denser air my bike is much more responsive and runs more crisply.I don't bother changing my jetting for each season.

Shouldn't really make much difference Kev - unless you're climing 2500 metres or more