Yamaha TRX850 Enthusiasts Forum

I bought a TRX a month ago and have ridden about 1000 km. I notice that when I stop at the lights that there is a strong smell of what I think is unburnt fuel. I've monitored fuel consumption and this is 13km/litre city and 20km/litre highway. I think this thing is running rich, and have others comment on this possibility. Recently changed the air filter, but apparently, this is not necessarily the source of the issue. Is this all typical and normal, or is there something I can do to make this thing run more economically than my Hummer.

90% chance it's your emulsion tubes in the carbs:

Basically they are the part that the metering needle runs in. They wear oval which results in rich running. See:

http://www.factorypro.com/products/Jets ... eedle_jets

http://www.factorypro.com/

Not expensive to replace, and a simple job as long as you are happy to take carbs apart.

Also see:

http://trx850.motomaniac.net/forum/view ... sion+tubes

Or search the forum for Emulsion tubes.

Oh and it's very common.

What Burty said. That was the fuel economy I was getting when I bought the bike. Now Its down to 180 - 190kms. And yes I've always had that wafty petrol smell coming from my bike. The bloody things run rich from the factory. Getting mine replaced this week with Factory Pro titanium kit (when it arrives ) Approx $190 for my kit or $130 for Genuine Yamaha. Try Bikebiz, Parramatta - they've a wealth of knowledge on TRXs. Their boss once built one with Ohlins everything and an Akrapovic 2-1. Don't know if they've still got it. I saw it under a sheet at the back of the shop a few years ago. Beautiful!

Bob

Hey guys, wonder if you can help regarding this fuel comsumption..

Mine also only does 200Km till I hit the reserve and it does smell of petrol a bit, a mate riding behind me last weekend said he was getting intoxicated with the smell coming off the bike…

Anyway, I should look at probably changing those emulsion tubes, air filter, balance the carbs…etc

Things is.. I've been told my bike has been Dynojeted…
The carbs are the standard ones, but my doubt is, if the bike has been dynojeted will the emulsion tubes be diferent from standard? Or will they be exactly the same and I can just go to Yamaha and order some new ones?

Is there also anyway of finding out of the bike was really dynojeted?
I'm thinking about doing the job this weekend…but want to be sure about what to buy so that I have everything I need when I start taking the bike apart..

Thnks!
JP

Pretty certain that the Dynojetting doesn't change the emulsion tubes. I would expect it to be needles and main-jets, maybe pilot jets.

You could ask Dynojet themselves. Other than that I think Phuk72 has first hand experience with the Dynojet kit on the TRX.

burty wrote:Pretty certain that the Dynojetting doesn't change the emulsion tubes. I would expect it to be needles and main-jets, maybe pilot jets.

You could ask Dynojet themselves. Other than that I think Phuk72 has first hand experience with the Dynojet kit on the TRX.

Is the correct answer

Hello again guys....

can anyone tell me which bit refers to the emulsion tubes?

I went to Yamaha, but not sure if it´s the bits marked 11 on the pic below...if it´s..they are only sold in one lot and it´s £27!!!



Can anyone confirm me which bit it is?

thanks!

Part 11 is the needle, part 9 is the needle jet block that holds the emulsion tube. Picture doesn't show it as a separate item but it is.
CYA, Kev.

cool!! so what I need is part 9 then? great!

The emulsion tube looks like the brass bit in this picture.



Removal is pretty simple, you have to get the carbs off the bike, the float chamber off and it becomes obvious from there.

In my experience the hardest part is actually releasing the screws to get the float chamber off. After a couple of times I replaced all the float chamber screws with hex bolts, as well as the top cover screws. Now I can get the float chambers off with an allen key which means I can do it in situ - well just so long as I release the carbs from the intake rubbers.

Yeah you do get the emulsion tubes with the Dynojet kit. Running rich is the main cause for sending riders behind you into a high... A few of my mates would complain about riding behind and getting dizzy! hehehe... But all good now, properly balanced and tuned my does about 280/290kms before hitting reserve.

(well, that's with a girl riding it anyway )

Mmmmhhhh…. So you say that you get the emulsion tubes with the Dynojet kit, but was posted before that the emulsion tubes are standard.

So what's the final answer guys?

Really need to sort this consumption out as it's only doing 190km to reserve now..

Call dynojet and ask.