I have PROOF that synthetic oils promote EVO leaks...
Seasoned HDF Member
Joined: Dec 2010
Posts: 7,736
Likes: 1,524
From: Coromandel Peninsula New Zealand
Go read a few more oil threads....and some "what is the best carby" ones too...
Stellar HDF Member
Joined: Jun 2006
Posts: 3,481
Likes: 11
From: NJ
Fair enough, BUT: if you have an Evo which is clearly NOT in need to be rebuilt (compression is perfect, running great, no smoke), are you really going to bother taking off the heads and jugs just because only Syn oil leaks? (remember there is a problem with studs on Evo - they technically have to be replaced with the newer design)
Just did 1K on the weekend, while being back to mineral for this season, and hell yeah - the leak stopped!
So I guess it's a borderline of "don't fix it if it ain't broken". Who cares if it leaks out some expensive sh|t which does not really have to be there in the first place!
Just did 1K on the weekend, while being back to mineral for this season, and hell yeah - the leak stopped!
So I guess it's a borderline of "don't fix it if it ain't broken". Who cares if it leaks out some expensive sh|t which does not really have to be there in the first place!
My response was in no way disrespecting your response but was letting you know that in my past experiences(over 25 years)and yet to ever see a motor spring a leak due to the wrong oil, period.
Rebuilt plenty of bike motors along with car and truck motors too and never seen it happen.
I guess anything is possible but never seen it.
Road Master
Joined: Jun 2009
Posts: 1,062
Likes: 18
From: Beautiful SW Missouri Ozark Mountain Country
I had a 79 Jeep CJ7, many moons ago. It would sometimes have a lifter that would stick, causing it to backfire. Some one suggested that I run it for 50 miles or so with a quart of ATF mixed in with my crank case oil so as to clean the lifters, oil galleys, etc. etc. Never really understood why this combo would have any cleaning properties since there is no detergent in ATF. Anyway, after I drain it, replaced it with fresh 20-50 and a new filter, it developed a horrible rear main seal leak. It would typically only leak while running (stands to reason) and would leak a full quart in 300 miles or so. Anyway, I asked an "old-timer" about this and he said that my dino engine oil coagulates over time and acts as a sealer or more like a cork (like stop-leak products) on seals and gaskets, and that the hydraulic type oil that I used cleaned this coagulated oil, and found a leak.
Get that? Found the leak. In other words, the leak was always there, but plugged up by coagulated oil. The ATF didn't cause it, it found it and cleaned it.
I believe that is what your synthetic oil is doing. But to me, if you want to split hairs, then the synthetic oil does cause leaks. If the leak was there and plugged up, then technically, there was no leak.
Get that? Found the leak. In other words, the leak was always there, but plugged up by coagulated oil. The ATF didn't cause it, it found it and cleaned it.
I believe that is what your synthetic oil is doing. But to me, if you want to split hairs, then the synthetic oil does cause leaks. If the leak was there and plugged up, then technically, there was no leak.
Stellar HDF Member
Joined: May 2009
Posts: 2,856
Likes: 127
From: Middle of Kansas
I guess the bottom line for me is, Mobil 1Vtwin 20-50 leaks in my EVO, but it stops leaking with Castrol GTX 20-50 dino oil. I am not sure how or why. I just know it does. If yours does not leak with synthetic, more power to you. When mine gets over 100,000 miles on it like some of my friends, I will put in better gaskets when I refurbish it. Glad some of you guys have never had leaks with synthetic in your EVO.
Seasoned HDF Member
Joined: Mar 2007
Posts: 66,948
Likes: 4,573
From: TOAK western branch
I had a 79 Jeep CJ7, many moons ago. It would sometimes have a lifter that would stick, causing it to backfire. Some one suggested that I run it for 50 miles or so with a quart of ATF mixed in with my crank case oil so as to clean the lifters, oil galleys, etc. etc. Never really understood why this combo would have any cleaning properties since there is no detergent in ATF. Anyway, after I drain it, replaced it with fresh 20-50 and a new filter, it developed a horrible rear main seal leak. It would typically only leak while running (stands to reason) and would leak a full quart in 300 miles or so. Anyway, I asked an "old-timer" about this and he said that my dino engine oil coagulates over time and acts as a sealer or more like a cork (like stop-leak products) on seals and gaskets, and that the hydraulic type oil that I used cleaned this coagulated oil, and found a leak.
Get that? Found the leak. In other words, the leak was always there, but plugged up by coagulated oil. The ATF didn't cause it, it found it and cleaned it.
I believe that is what your synthetic oil is doing. But to me, if you want to split hairs, then the synthetic oil does cause leaks. If the leak was there and plugged up, then technically, there was no leak.
Get that? Found the leak. In other words, the leak was always there, but plugged up by coagulated oil. The ATF didn't cause it, it found it and cleaned it.
I believe that is what your synthetic oil is doing. But to me, if you want to split hairs, then the synthetic oil does cause leaks. If the leak was there and plugged up, then technically, there was no leak.
Seasoned HDF Member
Joined: Dec 2010
Posts: 7,736
Likes: 1,524
From: Coromandel Peninsula New Zealand
Its the same end result....seen leaks with syn and they go when Dino put in too many times now to accept any other viewpoint....who cares what "causes" it....I never recommend synth in an Evo.
Seasoned HDF Member
Joined: Sep 2010
Posts: 10,236
Likes: 798
From: Indiana
An oil change is due on my Evo. I've been running Mobil synth. AND, the motor leaks (wet base gasket and 2 drops on the floor when parked).
I'll change it to dino and report back.
I'll change it to dino and report back.
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Road Captain
Joined: Nov 2007
Posts: 517
Likes: 6
From: Ottawa, ON
LMFAO! This thread is getting funnier and funnier. Well, just to clarify a bit on my humble opinion:
I am not saying that syn oil causes leaks per se ;
I agree that there is a problem with a motor that leaks syn oil ;
all I'm saying this problem by itself is not big enough to tear the motor apart if it doesn't leak dino oil, that's all
I am not saying that syn oil causes leaks per se ;
I agree that there is a problem with a motor that leaks syn oil ;
all I'm saying this problem by itself is not big enough to tear the motor apart if it doesn't leak dino oil, that's all
Road Master
Joined: May 2009
Posts: 1,232
Likes: 8
From: Powder Springs, GA
I also think a good point is that there is no proof that syn would extend the life of an EVO. There are so many high mile EVO's out there that run all kinds of oil. I think it also speaks to us as EVO's riders that we keep are bike maintained no matter what we run.
So can't we all just get along
So can't we all just get along