I've been using the red bottle of honda brand gear oil. Works good and reasonably priced. Been using it for about 18 years plus with no problems. I never cared for anything that had Royal Purple on the label. Not trying to badmouth your premix, just give my opinion. I prefer Maxima 927 premix for non powervalved motors and Maxima Super M for powervalved motors.

 

X2....

I'm not sure what to run in my trx250r. it has a hinson clutch and is bored over and runs on 110 octane and royal purple

Use 650 ml's to refill crankcase that has had oil in it before, and 750 ml's for freshly build bottom ends.

Carlos

 

Castor based oils offer better film protection(especially when pushed to the limit), but burn just slightly dirtier. They tend to have just a little bit more carbon buildup. Super M is a synthetic and burns just a little cleaner causing less carbon buildup, which helps keep powervalve service intervals(cleaning it so it operates properly) less frequent. For me it's just a matter of personal preference. Being jetted properly obviously helps the most to prevent carbon build up, but once you get there, then it just comes down to personal preference. 927 is IMO the best premix for a nonpowervalved R. It's all I run in all my nonpowervalved stuff. The YZ 250 gets Super M though, and it does also like a lighter weight oil in the crankcase then the red honda oil(which is like 80W). I run Honda 10 W40 in it.

 

X2....right on the money; run any Castor or Synthetic/Castor Blend like 927, and the carbon build up is more excessive than a straight Synthetic. Simple maintenence prevents PV failures, for that matter most failures.

Carlos

 

Not trying to be a wiseguy, but I would rather service a powervalve slightly more often and get longer service life out of my engine.... That's just me... OP: Honda 250r Service manual calls for 10w-40 for the transmission

 

Good info Dennis.

 

Service manual says that, but bottle of oil also says for all cr's and 250r's. Mr. Wiseguy. JK about the wiseguy

 

Btw nice avatar Doug.

 

if you visit any of the dirtbike forums youll see most of them goobers use 40:1-60:1 motorex or amsoil or motul. and theres plenty of pics with gummed powervalves. from time to time youll still have to clean the valve assembly regardless what oil you use. might be alittle more accumulation using castor oil but i dont think it will be a big deal. ive got several bikes but only one has a PV and its ktm but i put a heavy dose of straight castor in it