Crank Case Oil

[jean1steve]

I have a 89 yz 125 I have been told to run ATF fluid in the crank Case But I can't find a manual for my bike and I dont want to ruin it Help!!! what should I run or where can I get a book.

 

[Senior KX Rider]

You prolly don't want ATF in your cranckcase :scream: but it won't harm the gearbox. I run type f atf in my bikes with good results

 

[dthoms]

I've never had an 89 YZ 125, but I believe the crank case is lubricated by the oil that you are suppose to mix into the gas, that you put in the tank ie, premix. Normally at a ratio anywhere from 32/1 to 50/1. Now the oil that goes into the transmission is another question. I prefer oils that were designed and engineered for a motorcyle, this is because I count I my bike get me in and out of some sticky situations. If I didn't know what to use I might even visit or call a Yamaha dealer!!!

 

[SIMO]

If you are talking about your gearbox, and I hope you are, there is a extensive discussion on this in the tech archives.