Anonymous (not verified)
Edited Date/Time
2/23/2015 2:41pm
A while back he said never to use a synthetic premix with a mineral tranny oil due to the fact that IF you ever have a leaky crank seal it will fry your top and bottom end because a black glue it creates. Didn't happen to me but at the shop someone brought there bike in and BAM crank was pretty much glued lol same with top end. Should have taken pictures but didnt think much of it. Turns out he used Rotella T and Redline. So Paw Paw I must ask, Would you rather use BelRay H1R with EXS in the tranny, Motul 800 with 300V in the tranny or K2 with Extra 4 in the tranny, knowing that it might happen. Just a question because I dont think that any of them will create the glue type stuff if mixed due to a bad crank seal. H1R and 800 have really high flash points which is good but K2 is sooo clean burning and has great additives. What do you think?
I would use any none synthetic 2 stroke oil with any trans oil.
If I were to use HR1 I would use type F trans fluid.
You can also use HR1 if you use a synthetic trans oil with the same base material in it. It's the use of different base materials in the 2 different oils that creates the issues if they are different, not the flash point.
Paw Paw
The kawi manual for my 250f says you can use either one and doesn't mention having to do anything special if switching from one to the other. I'm thinking it should be fine especially if I change the oil filter while I'm at it but the fact that doing an oil change doesn't get out every single drop of oil in the motor leaves me to wonder.
I use it in all my 4 stroke bikes, generators, autos and rv's now. It is a Diesel oil, but it is also rated for wet clutches in motorcycles. I run it 250F's and 450F's.
I find it runs cleaner than Mobile 1.
Paw Paw
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Paw Paw
Also, it seems to me the bike would have to be getting a pretty big ingestion of gear oil for a decent period of time and really be running like crap before this would happen. Hopefully running so crappy that you'd notice it and do something long before the black glue crank disease struck.
I think it likely has more to do with the fact that it is "gear oil" getting in the engine than the fact that it is petroleum or synthetic based. Gear specific oils are heavy in zinc content, etc... things that are good for gears but maybe not so much for engines. If you run "motor oil" in your tranny you're probably OK with it getting in your crank whether it's synthetic or not.
If you use a synthetic premix, then use a synthetic trans oil or use petroleum based in both places and you will have no issue.
I can't tell you how many engines I have seen this in over the years and I have been told I am nuts, but the facts hold this out to be fact time and time again. In fact a small trans oil leak by a seal seems to be worst than a large leak.
In general, check the base material in the oils you select to use to be sure you are not mixing different base materials and you will be ok. I discovered this many years ago when I kept seeing the same issue repeating itself.
Those are my last words on the subject as it is based on over 40 years of working on bikes.
Paw Paw
Don't get butt hurt about it. Let's run this to ground. I've also worked on bikes a long time. H1R in the fuel and Bel Ray Gear saver (petroleum based I think) in the trans was my favorite combo for years. Never had a prob. And I'd guess I probably had a crank seal weeping a time or 2. Right now I run Maxima Super-M and Bel-Ray gear saver. Hope I don't get the black glue crank. I would still be running H1R except I tried Super-M years ago and it ran great so I just kept using it.
I just think it has to be something more specific to certain combos of oils or you'd see it happening a lot more frequently.
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