Yamaha TRX850 Enthusiasts Forum

Hi guys im hoping you lot can put me on to something here...

Ive got my trx up and running and finally had it on the road for a quick 20mile spin.

Problem is it feels quite rough and vibratey whilst riding, and it feels like it doesnt even have the power of my old diversion 600.

At lights when warm it wants to stall (could just be the idle needs increasing) but the idle is also quite lumpy and can fluctuate 500rpm.

I think i have all the hoses on the right way round but i may check again, has anyone any further info?

Thom wrote:Hi guys im hoping you lot can put me on to something here...

Ive got my trx up and running and finally had it on the road for a quick 20mile spin.

Problem is it feels quite rough and vibratey whilst riding, and it feels like it doesnt even have the power of my old diversion 600.

At lights when warm it wants to stall (could just be the idle needs increasing) but the idle is also quite lumpy and can fluctuate 500rpm.

I think i have all the hoses on the right way round but i may check again, has anyone any further info?

When warm...quick twist on the throttle and it should go back dead on idle again...if chasing up high - to lean and if dropping and almost stalling - to rich.
How long have the carbs run without changing needles-needlejets

Hey mate, thanks for that, theres no stability in the revs after revving on leaving the bike, it bounces about all over the place, and like i say the power feels really low conpared to what i expected.

I do have a K and N panel filter and race cans but its been said thats perfect for the trx on standard jetting.

I couldnt tell you about the jets but the bike has 28kmiles.

May be worth stripping them down and having a look?

Thom wrote:Hey mate, thanks for that, theres no stability in the revs after revving on leaving the bike, it bounces about all over the place, and like i say the power feels really low conpared to what i expected.

I do have a K and N panel filter and race cans but its been said thats perfect for the trx on standard jetting.

I couldnt tell you about the jets but the bike has 28kmiles.

May be worth stripping them down and having a look?

Hmm, check the choke first...IIRC some has had problems with a stuck choke...then it will be struggling when warmed up!

ive just replaced the cable and all parts appear to move freely and are well lubed!

Thom wrote:ive just replaced the cable and all parts appear to move freely and are well lubed!

Ok, i´d double check it as it´s an easy thing...probably very worn tubes/needles then.

Cheers, could it possibly be kinked vacuum hoses from the inlets to the fuel tap/vacuum pump?

I'm thinking my RHS cylinder may have a kinked pipe now that ive scoured the forum?

Or maybe i need to strip and clean the carbs thoroughly...

I'd first check you hoses for kinks plus the tank breather hose as they are the easiest things to check. Could be a kinky pipe leading to fuel starvation.

After that, probably emulsion tubes which tend to go around 30k miles.

could i ask if anyone knows which vacuum hose connects where as ive had problems trying to find a diagram or figure out the order.

Thom wrote:could i ask if anyone knows which vacuum hose connects where as ive had problems trying to find a diagram or figure out the order.

Aren´t they so short you can´t put them wrong!? Either way one to pump and one to open up the fueltap up...

My problem comes from the fact one of mine had been cut and rejoined in the past (i think i may replace this with clear tubing i have lying around). So i dont quite know what goes where, somewhat trial and error.

L/h inlet stub to pump, r/h to small connector on tap if i remember correctly?

I've now noticed ive developed a fuel leak since its maiden voyage and having filled the tank full.

Hopefully its something simple like a stuck float valve but we'll see in a few hours

make sure that you DONT.. have the fuel tap on PRIMARY setting [horizontal] as you might find an engine full of fuel ..if you have a carb problem that is...the primary setting is to be used when the carbs have been run out of fuel all together and need to be replenished as soon as possible ...to be used with caution with some worn carbs these days...

alextrx850 wrote:make sure that you DONT.. have the fuel tap on PRIMARY setting [horizontal] as you might find an engine full of fuel ..if you have a carb problem that is...the primary setting is to be used when the carbs have been run out of fuel all together and need to be replenished as soon as possible ...to be used with caution with some worn carbs these days...

[pedant mode on] it's PRIME not primary [off]