CR250 80W Gear oil or 10W 40?

12 replies to this topic
  • yamarider426

Posted April 09, 2009 - 06:23 AM


Hey Guys I need some help here
Just rebuilt a 1990 CR 250 and in the manual it says to use 10w 40.

Its been a while since I have messed with a 2stroker but it seems I used to run some honda gear oil 80w in my old bike.

Any sugestions?

  • russell3

Posted April 09, 2009 - 06:34 AM


As long as ur bike is stock, I would trust the manual. If in doubt, call the honda shop and they should be able to tell you over the phone.


Posted April 09, 2009 - 07:32 AM


Both will work just fine. A lot of riders use Rotella T 15-45w with great success, just change any oil you use often.

  • Kyron

Posted April 09, 2009 - 12:40 PM


Your going to get many diffrent opinions........

I've used everything from cheapy 10-40w to 80w and that Rottela, even Automatic Trans fluid and GM auto-trac fluid (transfercase oil)

It will alll work........

IMO what is more important is that you change it.

  • Big_G_Hall

Posted April 09, 2009 - 12:54 PM


10W-40 motor oil is basically the same viscosity as 80-85w gear oil. I run Honda HP 80-85w in my 250. Everyone has their own opinion...but like russell said, you can't go wrong sticking to the manual.

  • russell3

Posted April 09, 2009 - 01:33 PM


Didn't think they were the same it a diffent standard of measurment or something? They do feel close, but most oils feel close to me...I couldn't tell the difference too much by feel. I can tell when I use 20W-50 in my xr600 when its 20 degrees's like molasses.

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  • CV4

Posted April 09, 2009 - 01:47 PM


Motor oil and gear oil are rated differently. An 80w gear oil is about the same viscosity as a 40w motor oil.

I use Rotella with no problems.

  • Big_G_Hall

Posted April 09, 2009 - 01:53 PM


20 degrees out! Dang man that's cold...

  • russell3

Posted April 09, 2009 - 01:55 PM


Motor oil and gear oil are rated differently. An 80w gear oil is about the same viscosity as a 40w motor oil.

I use Rotella with no problems.

Good to know! I didn't know they used a different rating system. I always thought it was the same.

  • russell3

Posted April 09, 2009 - 02:02 PM


20 degrees out! Dang man that's cold...

Nice article! It's all great stuff to know. I live in utah and on winter days, it got COLD! Usually in my xr600, i would go down to 10-40 and then switch back to 20-50 in the summer because it was really hot in the summer. With 20-50 in winter, I could barely get it started and then sometimes I could hear the valves for a second or two because of no lube. :thumbsup: that's why I went to 10-40 in the winter.

  • 1987CR250R

Posted April 09, 2009 - 05:46 PM


Honda transmissions are very tolerant. They'll take whatever you put in them as long as you change it frequently.

  • yamarider426

Posted April 13, 2009 - 09:43 AM


:p Thanks for the advice guys!

  • WoodyHonda166

Posted November 13, 2010 - 03:57 PM


That is the BEST advice! I use PJ1 10w-40 in my CR125. Recently saw an add for Bel-Ray 80w gear oil and thought I had hit the jackpot. Now, I find out that they are about the same viscosity, just rated on a different scale. I would really like to try out 20w-50 motor oil and see how that runs, my engine being a 2-stroke and in the winter at that, I am hoping for the molasses effect on my clutch in any case (using 10w-40, my clutch is constantly changing tolerance according to simple operating temperature, hoping the 20w-50 will help maintain smoother, more consistent clutch operation along with the benefits of added tranny protection).

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