[old mad max]

OK guys I did it and now regret it. )o; At 10,000 miles on my 06 the base gasket had a verrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrry small leak that I would wipe off every 100 miles at fill-ups.. That was with yamalube dino oil. I got talked into trying ams oil 10/40 full syn.......... Now it leaks like H%$^%&^*ll. 5 miles and I'm wiping.. I am so P%$^%&^*ed. I told myself "DON'T" do it.. OMM.

 

[lizrdbrth]

Yep. Them smaller molecules can find more holes in the fence than the bign's.



Try switching back untill you get that base gasket fixed. It'll slow it down a bit.

 

[n2o2diver]

My 2005 was the same. No leak till about 5k miles. Soon as I put synthetic in it, it bled like a stuck pig. Switching back to dino did seem to slow it. This weekend I pulled the cylinder, the base gasket had almost completely disintegrated.

 

[admiral]

Me too! 2005 model and ran dino oil until last fall when I switched to full synthetic. Prior to synthetic - no leak. After the switch, I can see some moisture. Basically, I smell it more than it leaks. Mine does not leak like you all are describing, so I guess I'm lucky so far. I've not had to add any oil inbetween oil changes. But I keep a close watch on it just the same.

 

[littletommy]

Hmmmmm...

This scares me a little. I was waiting until I had 2000 miles on mine and was planning on switching to synthetic. I wipe away a little film once in a while from one side of the head gasket, not much at all, but still...



I wonder after reading this, if I should just be happy with using non-synthetic oil.



I am getting ready to strip down the bike, do some painting, and spruce it up a bit soon. I'd be upset if I switched over and it started leaking worse than it is now. Thinking I better put new gaskets in the top end while it is down and maybe I should just stay with non-synthetic. Any comments?

 

[old mad max]

I don't why I changed........ Well I do, My wife always complained that hers shifted harder than it should.. So I thought let's give full syn a try.. As long as I was changing hers I would change mine...... First thing I told her was, I sure hope they don't start leaking. Hmmmmmmmmmmmmmmmmmmmmmmmmmm.. Oh I hate being right.. I have two 2010 gaskets in the bike shed just waiting.. DARN. OMM.

 

[littletommy]

I don't why I changed........ Well I do, My wife always complained that hers shifted harder than it should.. So I thought let's give full syn a try.. As long as I was changing hers I would change mine...... First thing I told her was, I sure hope they don't start leaking. Hmmmmmmmmmmmmmmmmmmmmmmmmmm.. Oh I hate being right.. I have two 2010 gaskets in the bike shed just waiting.. DARN. OMM.

That is why I was thinking about switching over, for the easier shifting, but I think I am changing my mind..

 

[admiral]

I too switched for shifting reasons. Synthetic oil may have some other great qualities, but I haven't really noticed a difference in regards to shifting, except for the first few miles after the change. Gonna stay with synthethic just the same.

 

[mattmus4357]

I never really thought about until now, but mine started leaking after I switched to synthetic too. I'm doing a long ride this weekend and I'll probably try to tackle the gasket after that. Not looking forward to it

 

[littletommy]

I wonder how many people out there only use non-synthetic oil?



It kinda seems like they have less problems.



I am thinking I am going to just keep using regular oil.

 

[lizrdbrth]

There's always a risk with synthetics.



This won't happen in all cases. Reasonably fresh motors or ones really well cared for with frequent dino oil changes will make the transition a lot better. If yours is weeping anywhere with dino, even sightly, it's an indication that your other seals may be too far gone to retain synthetics. I'd stick with dino or at least replace all the seals before transitioning to synthetic or synthetic blends.



The base gasket is sort of a crapshoot. It's not really a wear component like a seal, but it may spew synthetic even if it isn't weeping now.

 

[littletommy]

There's always a risk with synthetics.



This won't happen in all cases. Reasonably fresh motors or ones really well cared for with frequent dino oil changes will make the transition a lot better. If yours is weeping anywhere with dino, even sightly, it's an indication that your other seals may be too far gone to retain synthetics. I'd stick with dino or at least replace all the seals before transitioning to synthetic or synthetic blends.



The base gasket is sort of a crapshoot. It's not really a wear component like a seal, but it may spew synthetic even if it isn't weeping now.

Exactly what I needed to hear Lizrdbrth, thank you.



My bike is a 87 and with under 2000 miles, it obviously sat for years, so for now, I am going to stick with non-synthetic.



Thanks again Lizrdbrth.

 

[mattmus4357]

Can you switch back to Dino oil after running synthetic? I've always heard not to do that

 

[admiral]

If yours is weeping anywhere with dino, even sightly, it's an indication that your other seals may be too far gone to retain synthetics.



The base gasket is sort of a crapshoot. It's not really a wear component like a seal, but it may spew synthetic even if it isn't weeping now.

LB thanks for the memory trigger comments.



I should also note, my engine was not weeping or leaking with the dino oil. Now, only my base gasket area shows any sign, and there's only a slight weep with syn oil and no seals are leaking.

 

[budgar]

It's not the synthetic VS the dino oil issue it's the viscosity. There is a big difference betwee 10 and 20 wt. that 10W will leak through good seals where 20W will not. Go to a 20/50 Syn and be a happy little camper. It's easier to try changing the viscosity then pulling the head and cylinder again

 

[lizrdbrth]

I'll speak only to what can occur AFTER changing to synthetic from dino.



Here's what happens to your seals on an older motor with a pure history of dino, and why they stay sealed unless you change to synthetic:



If you've ever replaced aseal you'll notice that hey have two "lips", inner and outter, with a groove in between. When they're new, soft and pliable a certain amount of oil creeps past the first lip into the oil receptacle (the groove) and gets trapped between the two lips, providing lubrication to the rotating countershaft (kicker shaft) or whatever protrusion the seal is trying to seal, and keeping the spinning shaft from tearing up the seal.



On a motor that's been run for a long time on dino without frequent changes the sludge from the dino begins to seal the motor from the inside. Less (or no) oil reaches the receptacle and the outter lip dries out and begins to shrink around the shaft. Its I.D. is then increased due to lathe effect from rubbing the dry shaft. Your seals are essentially junk, but they still seal, partly BECAUSE they're junk. Sorta.



Then you switch to synthetic. It removes all the sludge sealing the back (crankcase) side of your seals. To a degree The newfound oil flow restores the seals and the outside lip which has increased in I.D. "plumps" back up and the i.d. becomes even bigger and leaks like a sieve.



The same thing happens to your base gasket (and to a lesser extent your valve cover, side cover or any other o-ring type gasket), except that it's simply a flat plate of fibrous material. A fine buildup of sludge may or may not be all that is keeping it from leaking from the inside, out.

 

[admiral]

I see. That's why I had to replace my valve covers this winter after I had switched to syn. Probably more seals/o-rings/gaskets to replace in the near(er) future.

 

[old mad max]

Sounds right........ )o; One last thing I should say---------------------------------------------------------pause------------------------------------------- "MY BAD" OMM.

 

[lizrdbrth]

I'm not rippin' on synthetics. It's good stuff and if your seals are good to begin with they should live quite a bit longer in the bargain. But if they ain't, you might be skrewt



If it makes you feel any better I'd have prolly risked it on a 2010 bike, as well.



Luck of the draw.

 

[old mad max]

Your 2010 "SHOULD" be OK.. My 06 I knew it was a ticking bomb.. I took my wifes bik for a ridee today and it "DID" shift smoother........ I just set up a gasket change with my buddies nephew. He did my buddies so Our dubs are next.. Wish me luck. OMM.