the dealer said to use 20/50 synthetic in my tranny now instead of Harley Davidson trans fluid and now when its hot outside the bike gets hot and the tranny works like its got no lube in it shouldn't I be using a heavier fluid like 80/ 90 weight in it

 

I run Belray gear saver 85/140 in my 5 speed.

 

Redline Shockproof has worked great for me, no matter how hot it gets.

 

Spectro GL-5 here, 75/140 I believe. Pricy, but good stuff....

 

To answer the question, yes you should be using a heavier gear oil in the tranny. Pick your flavor, syn or conventional, and it will smooth things out and quiet things down in your tranny.

 

Don't buy his/HD's BS, 20/50 syn is engine oil. It's not a gear lube, which is what should be used in a tranny. Baker Transmission use Spectro. I happen to like Redline Shockproof.
Check out Baker's website. There are several other gear lubes that will also work. Good luck.

 

Personally I would never put a motor oil in my transmission. I don't care if it says it's a 3 way oil. I use a 75/140 weight gear oil. You can get conventional, synthetic, or semi synthetic. Harley used to make a semi synthetic but stopped making it when sync 3 came out. In my opinion gears that are constantly meshed in an oil bath need a high viscosity gear oil.

 

+1 and in my SE 6 speed in my 2000.

 

I've never run engine oil in my transmission. Ignore your dealer and follow the owners manual, at the least! I've just put Redline in my bike for the first time, but it's early days for me. We also have a separate oils section in this Tech area, where you will find endless discussion and quickly get swamped in the stuff!

 

what does bruce jenners fluids have to do with an HD forum?