I used 75W-90 severe gear oil in the transmission last change per other oil thread recommendations. However, I noticed on the AMSOIL cross reference chart (see link below) that I should be using 20W-50 motorcycle oil in the transmission instead because the part no. in my service manual is 99851-05. I've also seen posts where people are upping to 75W-110 or even 75W-140. I'm a little on which direction to actually go and looking for some guidance.

http://www.amsoil.com/products/stree...oil_chart.aspx

 

I have 75-90 in my tranny, not sure what was in there previously as I just got the bike in March. I have not noticed a big improvement, still clunky at times.

 

I think you will find that engine oil viscosity and gear oil viscosity are measured differently. You are using the correct grade of oil. Your bike will thank you for it.

 

The 75W-90 I've been running seems to work great to me. No problem finding neutral from whatever was in there last year when I got it. Just saw the chart and it spooked me a bit. I do notice it shifts a bit harder after running in heat for a while. Wondering if I should make the jump to 75W-110 or 75W-140?

 

I have been using 75 90 amsoil severe gear oil in my tranny for 50,000 miles ,No problems at all . Good Choice

 

+1 onda severe gear

 

As an anmsoil dealer I can tell you there is nothing wrong with using the severe gear oil..however, you have the option of using the 20w50(MCV) for all three lube points (motor, tranny, primary)

The choice is yours and everyone will have an opinion.

 

You can run the gear oil 15-20,000 miles. I use redline 75w250 shockproof heavy gear oil and change it at 3 years. No fuzz on the magnet. Motor oil is for motors and gear oil is for gears.