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(04-14-2015, 01:47 AM)mininsx_imp Wrote: Just curious, the guys with the leaks, what kind of oil are you using? I've read for years where synthetic oil will sometimes seep out and dino oil won't.
That is an ancient story when synthetics first came out (in the late sixties I think). The reason for that is that oils have seal swelling additives that help the seals remain tight, and the early synthetics either didn't use them or used a different type of additive which sometimes caused leaks after petroleum oils had been used. It hasn't been an issue for over 30 years.
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(04-14-2015, 04:08 AM)FJR919_imp Wrote: (04-14-2015, 01:47 AM)mininsx_imp Wrote: Just curious, the guys with the leaks, what kind of oil are you using? I've read for years where synthetic oil will sometimes seep out and dino oil won't.
That is an ancient story when synthetics first came out (in the late sixties I think). The reason for that is that oils have seal swelling additives that help the seals remain tight, and the early synthetics either didn't use them or used a different type of additive which sometimes caused leaks after petroleum oils had been used. It hasn't been an issue for over 30 years.
That is an ancient story when synthetics first came out (in the late sixties I think). The reason for that is that oils have seal swelling additives that help the seals remain tight, and the early synthetics either didn't use them or used a different type of additive which sometimes caused leaks after petroleum oils had been used. It hasn't been an issue for over 30 years.
I haven't had a computer for that long, and I've read on car and bike message boards where seepage can happen with synthetic oil. I'm not saying that's the problem, I'm just asking what type of oil is used.
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Having read many technical articles on synthetic oils, I've never read of an oil leak problem from using them. In 50 years of doing my own maintenance on my cars and motorcycles, I had many more oil leak problems before synthetic oils were available. Every oil leak I have repaired has been caused by defective gaskets or seals, usually from normal wear and aging or the seal or gasket being improperly installed. I switched to synthetic oils exclusively about 15 years ago and have never had any problems.
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If you have an ol' BMW K model, which is older than 20 years and you used mineral oil the whole time, you don't want to switch to synthetic. That would cause leaking oil seals for pretty sure, especially the one from the engine to the dry clutch, which then may cause an oiled clutch problem.
However, when you used synthetic all the time already: no problem at all and no issue to continue using it.
Yet I don't think at all, this is a problem with the CB 1100.
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I use syn in all my old bikes. '77, '78s and '83. Plus everything else I own. No leaks.
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In the past I've looked into this claim that synthetic oil will leak past your seals. From reading the internet reports and discussions It seems that this is not true in a modern motorcycle engine, but there is enough reports of problems that it is true of older engines from the 70s including Honda and BMW, and also many Harleys right up to the late 90s, but not beyond.
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Went for a sixty mile ride today, I just found the same type of leak.
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I had the same oil leak fixed about the 3500mile mark (I'd have to check my records to know for sure). Mechanic pulled the cover to check valve clearance and found a gasket problem. Honda had a problem with incorrectly installed rubber gaskets. Part of the gasket material gets bunched up and folds over. Mine was fixed under warranty and I've been leak free ever since (12k service sched for next week). Since it is a known/acknowledged problem by Honda, I hope you leaky folks have the same luck I had.
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Good info, my warranty has expired, I will first try to retorque the valve cover, if that doesn't work then maybe I will pull the cover and look for any fold over gaskets and replace if necessary, Thanks jodyz
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Don't forget to put sealant in the "semi-circular cut-outs" using Three Bond 5211C or equivalent. Manual shows it going at the top of each cutout (both sides) where the cover mates with the head. I'm sure you can see where by looking before you remove the cover.
If you have a manual, sorry for the above.
