Suzuki 2 Strokes

I am finally getting close to kicking over my rebuilt T500. Any issues running modern full synthetic 10w40 motorcycle rated oil in the transmission? Or if you start to have a crank seal leak would this oil be detrimental to being sucked in as they like to do.

I've been using Putoline GP10 in my T500 race engines with no issues. It does get changed fairly regularly though so I can't vouch for 5000 miles on the road.

Cheers Geoff

At the risk of kicking off an oil debate again I would just use any decent-quality, 4 stroke motorcycle-specific oil for the gearbox. I used to get whichever of Castrol / Silkolene / Putoline semi-synth 10W40 was cheapest when a change was needed.

Any bike-specific modern oil is gonna be better than what was available in the 70s. And it's probably better to change the oil often rather leave it in, because of the shearing effect in the gearbox (although I think Suzi's advice to change every 1,500 miles is WAY too much - a contemporary Honda or Kawasaki 4-cylinder 4-stroke had the same change intervals, and in those bikes the oil had to lube the entire motor as well as the gearbox & clutch, AND get full of combustion by-products .... I reckon every 3,000 miles is fine).

Hypoid gear lube. GL5-rated 75-90 t
castrol syntrax limited slip 75w140 friction modifier
Shell-Advance-Ultra-4T-10W-40 has been recommended to me.


this is what one guy said on F/BOOK
The two unique things that motorcycle oils have to put up with are not causing premature wear to the wet clutch by making plate slipping easier and preventing oil breakdown from the transmission gear shear action which can lead to gear pitting and transmission damage. I always look to see if the oil meets JASO (Japanese Automotive Standards Organization) MA or MA2. This standard addresses these two issues and the JASO listing says it it good for the application. It is cheap insurance for the bike especially for earlier Titans with the smaller oil capacity. I believe all motorcycle oils meet this standard and at least diesel oil Shell Rotella T6 5-40 synthetic does as well. I am sure there are others but I have used T6 for years and you can get it at Walmart for low cost....

thanks all! it was pretty much what I figured but I wanted to safe than sorry.

JASO MA1 and MA2 rated oils were developed for 4 stroke motorcycles with crank train, transmission and wet clutch sharing the same engine case and oil.
Suzuki T500 is not such a motorcycle.
There are API GL oil specifications for transmissions with or without wet clutches. GL5 (e.g 80W90, 75W90, 75W140) is the way to go, but in case of clutch slippage, switch to GL4+ (GL4/5 on some markets).

I lived on a farm in my youth and we only ever had one oil for everything - AgriCastrol !

At a pinch we would even mix it up for Petroil in our Fizzies and BSA Bantams - Dad always told us to give teh tank a good shake between your knees though before starting off. Not sure it would be any good as 2T in a race engine but I'd still stick it in a gearbox and probably a 4T bike.

Cheers