125-200cc What gearbox oil are you using?

Apologise if its been discussed before .
What be interesting to know what type of oil everyone is using and the feedback!Especially,whether the type of oil has any influence on the "milky colour"?

For example, manual on SMS 125 (ALL years) recommends 4T 5W-40 .I am not able to get this locally,so I got Castrol MTX gear box oil ,10W-40 ,which has a red "atf" colour.Didnt take long to go milky colour ,so wondering if this is related!

Thanks

If it's turning milky you've got water in it, probably a coolant leak. Are you losing coolant?
I'm assuming you don't do deep creek crossings, which are another source of water in gearbox oil.

No rain riding for me at all,just sunshine What gearbox oil do you use and how often do you change it?Coolant loss is unoticeable....

I do use ATF oil as i had trouble with my clutch from the very first day owning the wr125.
Since i switched to ATF all problems are gone.

milkly oil =(more then likely) H2O in it...

+1 for ATF

you're going to get a whole load of different answers with box oil, loads of people do use atf and seem to be fine with it. Personally I use a fully synthetic 2 stroke light gearbox oil, 75w, any of them seem fine, putoline is well priced at £10 a litre, or you can get bulk buy ones in 5 litre containers on ebay that work out much cheaper. I change mine at what I think is 800 miles[ only guessing because my speedo is dead] or in hours its about 40

My CR150 had Belray gear saver in the gearbox when I bought it, and I hated it.
I use 15/40 Rotella, but maybe I'll try ATF. My Can-Am liked it, but the race bike (RM125) before the CR sure didn't.

My bike seems to really like Rotella.
Actually, I've switched to Rotella in all my bikes with excellent (IMO) results.
Actual results may vary, some settling of contents may occur.

I understand that !Just amazed that people are not taking notice of Husqvarna´s gear box oil viscosity recommendation and have their preferrences through their very own experience ,which is great .
I mean ,like in your case,you are using 75W ,whilst on the Husky manual it recommends 5W 40!

Rotella 5w40 full synthetic in the blue bottle

The water in the oil is common if you hit a water crossing with a warm engine. The engine rapidly cools and sucks water up the trans vent hose like a straw. You can either reroute the vent hose to the air box or do like I did and simply drill a small hole in the vent hose near where it hooks in to the transmission, this will prevent siphoning.

On my WR300'2010 I also suffered the grey trans oil, in my case I think it was most probably cause of the vent hose. I changed the plastic 'L' piece that goes on the cases and installed it with some good loctite silicon (joint former) and I also routed the vent up and into the airbox.

With that I got very little humidity into the transmission. I think the remaining moisture is related to pressure washing the bike and pointing too close to the seals for example in the kick starter area or the shifter...

Regarding oil recommendation (I really love oil threads, I do !), I'm using UTTO (Universal Tractor Transmission Oil) right now and I really like the feeling of the transmission and the clutch. It is somewhat high on viscosity (20W30 mineral) and need some minutes to warm up but then the feeling is great in my opinion. It is a GL-4 trans oil and I think it protects the transmission very well, little to no shavings on the drain-plug-magnet. I could not tell that from other oils used before...
I'm on my second 5L bottle and I think I'll stick using it, my clutch is also receiving a lot of abuse and it's still on the first set of disks

Greetz !

Thanks mate,will do that.Good advice.
No wet riding here for me as it's a supermoto but could be something to do my son pressure washing it,So no more of that.

Another thing that will make your transmission oil look grey and milky is a Barnett clutch. I have a Barnett clutch in my YZ125 and my oil always looks terrible but nothing magnetic and when I put a new crankshaft and top end in it I inspected every part and it looked like new. The grey matter which must be clutch dust will settle out of the oil if the oil is left in the drain pan for a few days. Also every now and then the clutch will stick when cold after the bike sits for a long time. My Beta trials bike did the same thing but after the initial start the clutch works perfect so no worries.

Thanks Hurky,for the feedback .I can associate with pressure washing being one reason and I will be altering the breather hose and re-routing it.Also,thanks for the oil recommendation
.I will defo try the GL-4 oil.If it's good for the WR300 ,it's good for the little sm125.
So,what do you think?Atletico or Real on Saturday?I saw the same teams and same final ,in Benfica stadium

I don't agree with what the manufactuer recomends, since they often have agreements in place with aftermarket companies to make customers spend their money on that product, rather than a just as good product from elsewhere. The blurb on the putoline box said for high performance two stroke motorcycle gearboxes, my husky is a high performance 2 stroke, and that is why I bought it it feels just as good now as it ever did, no notchiness or anything

heres another vote for the rotella...i use the full synthetic 5w40 stuff. i get the least amount of shavings on the magnet with it, much less than atf.

I vote for Shell Rottela T6 5 w 40. I love this stuff.

Paw Paw