A forum for owners of Yamaha TTR250 trail and enduro bikes!

barra8 · Member

White Smoke

Moose · Member

2006 TTR250.. Approx 10,000 k's.. This thing sat for a long time after blowing a clutch.. Finally got it started and huge amounts of white smoke came out of it. Mind you it had been cranked alot and about half a can of Start You Bastard in the carby..

Anyway it now starts 1st or 2nd go with kick and nearly every go with starter and idles and revs like a dream.no rattles.does not miss a beat. Funny thing is some days stuff all smoke and others a bit more.. When i say a bit more.. Little bit less than a 2 stroke..

Now the previous own has changed the muffler (from a Husqvarna of some sort) and I am not sure if he has been playing around with the jets etc..

Has anyone seen a fuel problem that will cause white smoke.. It is not thick like normal worn ring smoke if that makes sense.. Perhaps it just needs a good flogging since sitting..

TTRfan · Super Guru

Hi there Moose!

If your white smoke doesn't smell of burnt oil then it may just be simple condensation.

I think your idea of taking it for a good run and getting everything hot is a good one. That should make sure any residual water in the silencer is cleared out.

It's worth taking the airbox cover off first to check there isn't any water in there and that the air filter is clean and oiled. Also take the drain pipe off the bottom of the airbox (part 16 in the fiche pic below) and make sure its empty and clean. Also empty anything out of the engine breather condenser drain pipe (part 28).

Let us know how you get on wink

Brian

airbox fiche.jpg

Moose · Member

Thanks.Will give it a go.. I have a powercore 4 to get rid of the strange thing they have put on it.. Air filter has been thrown out it was that bad. :). The bike needs to be stripped down and have some work done to it but just trying to work out if the motor needs to come out before i start... Will put some decent fuel in it and give it a run...

Moose · Member

I cleaned all of the crap off the motor today from the oil leak. fixed the oil leak and threw out the crappy muffler thay had fitted. Put some decent fuel in it.. Could only really let it idle where it was but still blows smoke.. sometimes more, sometimes less.. At least it is rideable now.. Other than that it starts 1st kick or just tap the starter..
Will see if i can take it for a run..
I wont strip the tank, tap etc yet.. If it still blows after a run i will strip the complete bike anyway as it needs a lot of cosmetic work.. If i do that i might just re ring it anyway and strip the carb

Thanks for your help..

barra8 · Guru

Sounds like a plan. Glad your getting it all sorted

....................

Jarrah.

barra8 · Guru

That is correct...The intake system is very sensitive to changes so maybe it is running lean or rich?. To check this take your spark plug out & see if it has a white crust build up. If it is it's running lean.

If it's black it may be running rich unless it is fouled with oil. If it is fouled with oil there is two possible causes.

The rings are bad -would be blowing smoke mainly when hot & throttle is put on suddendly. (may be accompanied by low compression)
The valve stem seals need replacing- would be blowing smoke until warm. After warm it may only smoke occationally when throttle is opened suddendly.

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I would be finding out if it's running lean or rich after replacing the air filter ect. & go from there first though.

Merry Christmas.

..............................

Jarrah

-- Edited by barra8 on Tuesday 25th of December 2012 02:09:07 AM

Moose · Member

I am still hoping it is running too lean... The smoke has a strange smell but not that typical burnt oil stink..
Have been reading that air leaks after the carb and also having no air filter in it wont be helping... ??

Merry xmas everyone..

barra8 · Guru

Sounds like valve stem seals to me-easy fix ,cheap & worth checking. If it's just white smoke & nothing more than it should'nt be the problem.

Don't mean to go on & on so i'll leave you to it. Let us know if what you do does not help with the smoke.

........................

Jarrah.

-- Edited by barra8 on Tuesday 25th of December 2012 03:20:33 PM

Moose · Member

As i dont know the history of this thing and from the way they had the muffler set up on this i get the feeling that have been messing around with it but have no idea what they were doing.
Went to the shed today and flicked it over.. Started 1st go, no choke and idle was spot on.. Not sure if a bike had crap compression it would run this well.
Smoke - faint smoke after about 10 secs..

Will get my hands on an air cleaner tomorrow, pull spark plug and then if still there i will do the carb..

Let you know what happens with plug and filter

barra8 · Guru

Sea foam is for the valves...to clean them & also the piston ect.

You suggest the compression is good it is more likely to be a valve stem seal from sitting.

Lol mingle your funny. Suggesting that the tank does'nt need a flush after sitting lol. Don't see how you figured that out confuse .

By the way read my post before you go replying stuff like that.

Mingle wrote:

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No thats wrong jarrah, brian suggested condensation in the airbox, not water in the gas tank or bowl.

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I would like for you to tell me where i said there would be water in the fuel tank. I just reasured what Brian said. Then i said...

You may want to flush & clean your tank & filters in th petc0ck valve (if not already done).- I'll make it simple for you since you can't understand why the tank should be cleaned...This is because fuel turns into sludge when left to sit so it's best to flush it & put new fuel in (like it says to do in the manual) .

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Jarrah.

-- Edited by barra8 on Wednesday 26th of December 2012 12:33:50 AM

mingle · Veteran Member

No thats wrong jarrah, brian suggested condensation in the airbox, not water in the gas tank or bowl. If the OP had water in the tank or bowl it would'nt fire up or hold idle at all. water and gas dont mix, and the water stays on the very bottom. I believe the OP is experiencing a stuck ring. try some seafoam or marvel mystery oil. added to the oil or fuel. but you might just have to open her up and srap that carbon

barra8 wrote:

As Brian suggests......It could be water in the fuel. Clean all mentioned.
You may want to flush & clean your tank & filters in th petc0ck valve (if not already done).
If its fuel related (too rich) it would blow blueish black smoke & smell nice (unburnt fuel) .
If it was rings needing replacing it would also be blueish black but not smell so nice (like oil) Also the plug would be fouled with oil.
White smoke is not a drama & just means it needs a run (usually).
The valves may have a little bit of corrosion on them so when they heat up they burn it off ''white''. Not a big problem.
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Just check your not running lean because of the new exhaust (not saying it's the problem)
#147 main with #50 pilot jet is a good place to start with an FMF or larger pipe.
I'm using #150 main with #50.5 & it seems a little bit rich if anything but it's better to be rich than lean.
I just turn the air/fuel mixture screw out 2 1/2 to compensate & it seems perfect. Yet to ride it though....can't wait!
If you can let us know what main jet & pilot is installed that would be helpfull.
...............................
Jarrah.

-- Edited by barra8 on Monday 24th of December 2012 08:22:08 AM

Moose · Member

Thanks for all of the suggestions... Had plenty of experience with cars but have not really done much bikes other than real crappers that keep on going no matter what you do to them.
Did not know these things could be so sensitive to air leaks before and after the motor and that the leaks could cause so many different issues..

I now have decent fuel in it and will get a new k & N and then ride it to see what happens.. Only reason it has me stumped is because it only has 10k on the clock and compression seems to be great.

The Marvel Mystery Oil and Seafoam were an interesting read.. After 17 years in the motor industry (mainly parts) have never heard of it..
Were you thinking an oil ring is playing up .. ?

Moose · Member

The whole bike needs to be stripped, cleaned and put back together but rather than trying to deal with it later in a nice re painted frame i figured i would try and sort out the motor issue first. If i cant sort it i will be better off doing the rings and head while the motor is out. Carby aswell. I dont think it has ever been washed.
Will get some help later also with Jets to suit the Powercore.. I have been reading that you need to do the jets or it might run worse than having a factory muffler..

barra8 · Guru

If you want to fit an fmf or similar you will need to start at #147 main with #50 pilot jet and work your way up to see how much fuel is needed.

I'd say if the motor is good then #150 main jet with #50-#50.5 pilot jet would suit just fine.

It's good that you want to sort it before riding it. Good luck with it & if you need help i'll be here.

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Jarrah.

barra8 · Guru

An old trick that i use before stripping the motor (if it still runs) is to warm it up to operating tempreture (not too hot)

give it some revs.....

take off the airfilter.....

Using a little spray bottle with demineralized water (or filtered water) in it,squirt the water in while giving some revs making sure you don't squirt too much water in at once.

Wait until the revs pick up.

Do this slowly & you will see heaps & heaps & heaps of steam/black/soot/ect ect come out

It does work & i have done it many times. This just makes the job of re-building the motor much easier as it steam cleans everything.

If you want to spend money you can use sea foam... Subaru upper engine cleaner is what i use but water does work.

This is what it will look like when cleaning... http://www.youtube.com/watch?v=pdd-9fS-5Fo

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Jarrah.

barra8 · Guru

How cheap is cheap? & i'll buy some from you if you can get it cheap enough. (if it's cool)

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Jarrah.

-- Edited by barra8 on Wednesday 26th of December 2012 10:15:12 AM

Moose · Member

We use to sell this stuff to the Bike shops by the carton... Should give it a hit with that and see what happens.. I still have access to it cheap..