I have a 2003 rm 250 and want too change the gearbox oil but am not sure what too use,I was told too use 10/40 motor oil but that does not sound right???

20w40 or 20w50 motor oil is just fine. Please, rate my answer. Thanks.

• A couple of things could be wrong. The clutch cable center wire could be frayed and catching up on the outer shell.
• The clutch cable is bent or has been hit and crushed.
• The outer and/or inner clutch hub is grooved and the friction plates are hanging up in the grooves.
• You changed the gearbox oil and put in synthetic oil or an oil with "Special" additives. Synthetics can swell the cork on the friction plates and cause problems. Only use 10w40 motor oil in the gearbox.
• A bad needle bearing at the pressure plate or on the shaft
• The clutch was re-assembled incorrectly.

Go to the following website for an exploded view of your clutch. Please rate my answer. Thanks.
www.babbittsonline.com/pages/parts/viewbybrand/default.aspx

Change gearbox oil, install a new spark plug. Check for spark before installing the plug. Remove, dis-assemble, and clean the carb by soaking it in denatured alcohol for 15 minutes then finish with a can of spray carb cleaner. Wear goggles to protect your eyes from the spray.
In stall a new air filter. Remove the gas tank and clean it out. Install an in-line fuel filter to prevent trash from the tank getting into the carb. Use a can of spray starting fluid on the air filter to aid in starting.

The standard mix is 4 ounces of two stroke engine oil to one gallon of gas. Do not use standard motor oil. Only use two stroke engine oil.

The engine doesn't use oil,the only oil it gets is from the 2 cycle oil mix in the gas,the transmission uses 85\90 transmission oil such as bel-ray or others. I would NOT reccomend running 10\40 in the trans...

hi,you arent going to like this ,but it is water from the cooling system getting into your transmission,rm bikes are famous for it,you will probably find that there is a seal on the back of the water pump (which is driven off the crank)has failed letting the water in to the gearbox,drain the gearbox,flush it before running it again,but get the faulty seal fixed first...hope this helps...cheers

If you put synthetic oil or an oil with "Special" additives in the gearbox the cork on the fiber friction plates may be swollen. The swelling can cause the clutch to stay engaged, Only use standard 10w40 motor oil in the gearbox. You will need new fiber friction plates if that is what has happened. Normally the only other three things that would cause the problem are a worn shift arm, a bent push rod and a badly worn cable.

You use normal engine oil in the engine(SAE 30).DO NOT use gearbox oil or clutch fluid as you will get problems with your clutch.

Please leave a fair comment if you feel I have helped you.

Thank you

What service work has been done in the last month? Any oil changes? Added oil to the gearbox? Clutch worked on? New cables? Was this a sudden overnight thing or has it been getting worse and worse and now the clutch won't disengage the motor at all? Below is a parts diagram of your clutch. Post a comment to get back to me. I am sure I can get you back on the road.

Hi .... Try this site for the oil.

http://www.opieoils.co.uk/c-852-recommend-an-oil-for-my-motorcycle.aspx

Other problem sounds like carb or air filter. Does it spit back through carb ?