20 Most Recent 2003 Yamaha YZ 250 - Page 5 Questions & Answers

Check the reeds pull the carb and take the 4 bolts from the intake and look at the reed cage and make sure they are closed

Check the points for proper gap and clean. The old school bikes used more than just coil and plugs. Also, often overlooked, check the kill switch connection. Often this is the case on Yamahas.

ALWAYS have a fire extinguisher on hand when working on carburetors.
Remove the water trap bowl at the bottom of the petcock, (gas valve). Is there any water or trash in the bowl? Drain a cup of gas from the tank. Is there any water or trash in the cup? Dump it, clean it and re-mount it, ( not all bikes have a water trap bowl ).

Drain the carburetor. There should be a screw on the lower side of the carb float bowl. Remove the screw then replace it after the fuel drains. Turn the gas back on and wait a minute for the carb to fill with gas. Install a new stock NGK spark plug and try to start the engine. If the bike doesn't start and run properly then shut off the gas and remove the carburetor from the engine.

Remove the float bowl and clean the entire carb with a spray carb cleaner from the auto parts store. Wear protective goggles to avoid getting spray in your eyes. Spray into all the little airways and fittings in the carb. Before putting the slide back in the throat of the carb, move the clip on the jet needle one notch lower. Put the rest of the carb back together, clean the air filter and install the carb. Let the float bowl fill then start the engine. This process should get you back on the road.

Please rate this solution. Thanks!

Repair manual

sounds like your going to have to split the casses to fix trany to me. sorry the same thing hapened to my 2001 blaster.

Here is a site with good info about modifying your bike. Thread My wr400 street conversion

just turn the gas off

check your shifting drum.may have left a pin out of the shifting drum.

Its not supposed to work on your bike "BUT" I have a 2006 raptor 660 CDI on my 02 warrior 350 and it works better than stock and is supposedly "non-compatible" with the warrior the only thing different with your bike and the 03 is the TPS

Without knowing all the variables here. How old is the clutch that is in the bike now? It may just be worn out, and need new fiber plates and discs put in it. Are all of the clutch springs the correct ones, or if they are old, might be time to replace them. When its slipping, what kind of riding are you doing ? in mud, sand, or on hard ground ? What size engine and bike do you have ? Is your clutch cable and adjuster the stock and correct pieces for your bike ? or aftermarket ? Have you had the clutch apart recently, and do you know for sure that you put it back together correctly ? ( See Service Manual ). Lots of variables to consider... without knowing, you might consider these things I have mentioned. Thanks.. Hopefully these will get you going again.

try youtube.com they have about everything

Oil rings are worn inside the motor.pretty much engine on it's way out.

strip gear box and check all selector forks and cogs for wear etc ! check gear lever shaft etc ! P...

As in all gears? Or just 1 spcific gear range? Might need to pull the transmission apart and have the gears "backcut" or just replace them entirely...

Springtime start ups after sitting up for awhile can be a problem. You have nothing to loose, spray some starting fluid into the air cleaner. That may be just what is needed for an easier spring start.

do you mean it sticks down after kicking ? if so the return spring or cog on the kicker are damaged ! remove side cover and you can see the problem ! P...

If its yz It is a 2 stroke and has on valves per say. It has a reed valve located between carb and head. Lots of times they need to be replaced or re-clearance (Make sure they are free of debri and flat on the housing.

hi there this could be a bad spark plug or the carbie jet blocked or if you have a fuel filter it could be blocked ,if the motor is smoking then may need new rings,at the worst you could have a broken ring which is not letting the piston move properly , hope this helps

Check and fix there in order: check spark plug gap and colour - replace if it has any cracks in the insulator;check air cleaner and clean thoroughly if at all dirty;remove and clean carby float bowl - if there is any sediment, replace or fit fuel filter, if there is "paint-looking" coating on anything, clean entire carby.

Your rear shock has oil in it that is a measured amount. But...also has a nitrogen charge. If this leaks out, you need to get the rear shock rebuilt.