Yamaha TRX850 Enthusiasts Forum

Hi Guys,

im having a bit of a problem here.
My TRX had some electrical problem because all of a sudden it started blowing the main fuse constantly i tried tracing the short bay unplugging everything cleaning the connectors(a few had some corrosion) and then pluging them back 1 by 1.
at the end everything was plugged back in with the main fuse still intact fired her up without the tank and it fired up right away
i thought ok it was probably the corrosion in the connectors. it kept shutting of as if it wasnt getting enough fuel(tank was not connected so didnt think anything of it).
fired her up a couple of times without any problems. and the it wouldt fire up anymore cranks i but doesnt even act as if it wants to fire up.
i measured the rectifier/regulator (youtube video) measures good.
checked for a spark there is a spark although it seems a bit weak(not too sure)
there is fuel getting into the carbs (checked the fuel drains)
opened up the carb to check the floats

im really at a loss here since i live in Suriname(south america) and as far as i know mines the only TRX here.
so nowhere to get spare parts to help find the problem.

im thinking of ordering a spare ecu spare rectifier and the relais but these will cost me quite some $ to get the here wouldnt mind if i knew this would fix the problem.

any advice would be very much apreciated.

Romano

I'd refit the tank back on and turn the fuel tap to the horisontal ( fuel tap bypass )
Then make sure the fuel vacume tube is on the tap as well.. ( this is the vacume line that is on the left carb manifold and runs to give vacume to the fuel tap to auto open..and with this line forgotten....will cause the left cylinder to run lean and misfire and stall.).
Also double check your connections and reaffirm earth wires.

I already reconnected the tank there is fuel going to the carbs.
i will recheck connections and grounding.
its also not the vaccuum these are all connected.
kinda cool backfiring when releasing the throtle in gear when the vaccuum is not connected.
thanks for your input.

So how has a trx gotten over to South America ?

alextrx850 wrote:So how has a trx gotten over to South America ?

i think imported from the netherlands.
i bought it local so not to sure .

did some more troubleshoorting today and this is getting stranger.
first try before i did anything on the bike it fired up but died right away (did this 3 times) after that nothing.
cleaned the carbs checked for a spark(i find the spark to be a litle weak of what im used to from 2 cycle engines)
checked all connectors it did act as if it would fire up once but nothing else.
after that i started removing connecters 1 by 1 and when i unpluged the 6 pin connecter from the dash it fired up right away shut down fired up right away again could even gas it (happy for the moment it seemed i had found the problem)
well hell no after that nothing anymore not even a cough with or without the connecter plugged.
i am really confused could i be the ECU???
i rellay can use all the help i can get.

There is a side stand cut out switch down on the stand base itself.
The wire for this runs up inside the front sprocket cover and could be chafing and earthing.
Otherwise if fuel is suspected, I'd buy an aerosol can of starting spray, ..spray that down the inlet chutes to the carbs,..be careful of a backfire.
Big chance it could be the side stand wire.

alextrx850 wrote:There is a side stand cut out switch down on the stand base itself.
The wire for this runs up inside the front sprocket cover and could be chafing and earthing.
Otherwise if fuel is suspected, I'd buy an aerosol can of starting spray, ..spray that down the inlet chutes to the carbs,..be careful of a backfire.
Big chance it could be the side stand wire.

i will check that out tomorrow i hope that that is the problem.
i dont think its fuel related im thinking more electrical since it started up right away when i unplugged the dashboard connecter

Meter your coils to check they are both OK.
They may start but usually fail once they get a little heat in them.

alextrx850 wrote:There is a side stand cut out switch down on the stand base itself.
The wire for this runs up inside the front sprocket cover and could be chafing and earthing.
Otherwise if fuel is suspected, I'd buy an aerosol can of starting spray, ..spray that down the inlet chutes to the carbs,..be careful of a backfire.
Big chance it could be the side stand wire.

im really confused now today i tried it with an aerosol can and it fired up wasnt running good but it started and i could gas it a bit so now all of a sudden it seems to be fuel related first the main fuse kept blowing that stopped now a fuel problem. this bike seems to have some gremlins in it any idea of what could be wrong with the carbs?
i have already cleaned them.

update :now the bike starts but backfires alot and doesnt keep running help help help!!!

Go into your personal settings and add your location to your side ID box Romano.
You might be close to someone who can call in.
Sounds like a couple of issues.

alextrx850 wrote:Go into your personal settings and add your location to your side ID box Romano.
You might be close to someone who can call in.
Sounds like a couple of issues.

Another update the bike starts now but initial start isnt what it should be takes a bit of cranking as soon as it's started it restart without hesitation.
Im starting to think my carbs have a problem I should probably look into another set online.
I will post my location but won't help as this is probably the only trx in the country.
So no help there I'm in this all alone

Good one Romano.
Be interesting to the local reaction to your trx when you get it running and out on it.
Being none about there.
Google Keyster trx850 carb kits.
They are what we use here in OZ, and work well...it's a full kit too with the jets and needles to do the job properly.
Also search on this site for the feedback too.

If it's been sitting a while it may just be fuel gummed up inside your carbies.
Think about what sort of fuel they use in South America too..
If it's an ethanol mix fuel, you may find a lot of degradation of rubber o rings and diaphragms.
May be worth your while to just systematically go through the fuel path, dismantle the fuel tap( it only a couple of screws) then move down to the vaccum pump again 3-4 screws, and check and clean each component and fuel / vaccum lines.
As Alex said, purchase 2 of the KY-0570 Keyster carb kits as they come with all new seals, o rings, needles , emulsion tubes and jets for the carbies.
http://www.ebay.com.au/itm/262228282694