Dirt Bike advice

[Lorne Day]

Today I picked up a 2002 YZ250 for a steal from a friend. It was last ridden 2 years ago when he wrecked it and tore up his knee. Now his wife wants the basement real estate back. It has a pipe, jetting, intake, seat and suspension upgrades. He put fresh fuel in it and tried to get it started, but it won't fire up. Here's what I think that I need to do.

remove, clean carb (do I need to remove the jets?)

new coolant (what kind?)

oil change

What else should I do/look for or should I take it in for a tune up? I've worked on bikes before, but I'm not too keen on disasembling the carb.

Any advice is appreciated.

 

[Chris P]

spark plugs, wires, air filter, gear lube, check the chain, check the magneto for spark

 

[Ben Poche]

if it is a 2stroke it needs oil in the fuel their is no oil change needed. i say the same as chris p

 

[Mike Dziubina]

if the bike sat with the same fuel for that long you may want to flush out the whole system... and again, everything chris p said

 

[Doyle Ptak]

Lorne, You should be able to just clean out the gas tank, make sure you also chean the screen in the petcock if it has one. Re-fill with gas and 2 stroke oil mixture. Remove the drain bolt on the bottom of the carband let some gas flow thru to get the crap out of the settling bowl, replace screw. Pull the spark plug and clean. With the plug out you can ground it against the engine and kick the engine over a few times to make sure that you have a spark. Re-install plug and hopefully the bike will fire up. It's only 4 years old, no need to replace plug wire or coolant. As mentioned earlier a 2 stroke engine only has gear lube for the transmission and clutch pack, no need to change these either yet.



Let us know how it goes.

 

[Aaron Yarbough]

Yes, you definately need to remove the jets from the carb! It's not hard, they just screw out......that will allow you to clean them because I would bet that 80% of your blockage is there because the holes in the jets are so small they gum very easy and fast. THe larger arreas, carburetor bowl etc don't clog as fast because they are not as small but i'm sure they still need to be cleaned.



Lastly, I think the gearbox uses oil, not gear lube (a lot higher viscosity), Check with Yamaha to see what viscosity they reccomend. My guess is that it will be a 40 weight oil.

 

[Douglas Studdard]

All are great suggestions but use simple 10w30 in the crankcase, that's what the specs say from Yamaha. I ride and race both a YZ125 and YZ250, can't figure out which I like better? Also check and/or clean the air filter under the seat. You are going to play hell getting that carb boot off the back of the carburator so I would install a new spark plug, clean the airfilter, and change the gearbox oil and then turn the choke on and try starting it. If you just can't get it going from there then pull the carb.



The 02' is a great bike as that year will interchange with most parts from 02-06 for plastic and such. Of course the started the aluminum frame in 05 so that wont changeout with it. You can buy a complete plastic kit, I recommend Acerbis, for around $120 and make the bike look nearly brand new. I recommend www.Motosport.com for all of your aftermarket needs, ask for Josh ext 5619.



Thanks Doug.

 

[Brian Curry]

Clean Carb(main jet, pilot jet, emulsion tube,etc),change Transmission oil. Pull the mag cover off and look for oil or anything leaking from here. With it being parked for so long the crank seal may have turned to goo. If that is the case, replace the seal (easily done from out the outside). If after you get it started check the transmission oil every day . If the PTO seal is shot, the motor will suck in trans oil(if it is really smoking bad).

 

[Lorne Day]

Thanks to everyone for the advice. I'll keep everyone posted on how it's going.

Doug, I've ordered stuff from Motosport.com already and have had great service. I do need a new rear fender, so that's where I'll go.



Thanks, Lorne