Engine Oil Seals

Further - You guys who think Yamaha gives a ShT about these old bikes are mistaken.
They do Not ! A different seal is often used as they do Not want to make a seal and just
substitute one that will work. Also I have tracked OEM prices for years and Yamaha often
( usually ) lowers the price on NLA items as they do not want anyone else to go into reproducing
these items. Yamaha holds any and all info about parts MUCH closer than the other Japanese
companies even though they will not do those parts again. It's all about selling New bikes and Not
about keeping what's sold going. If they have an old part it's because the same is now on a new bike.
Yamaha also assigns a new number when a part is used again and usually will not give a superceed
number or a detailed size or description - Some parts have up to 60 different numbers for the same
item. Don't expect to reuse Old Seals, Gaskets or O-rings and no one who Knows would.
 
Don't expect to reuse Old Seals, Gaskets or O-rings and no one who Knows would.
Seals, no, because it's safe to assume you destroyed it when you removed it. Gaskets and o-rings, it depends. I've used the same right cover gasket a dozen times and not a drip. Savings, $200+. O-rings, reuse them unless they're too flattened to work. Where does your name come from, did you trade an XS for a lawn mower? Or did you trade a bunch of XSs for a car? Or did you misspell traitor? Inquiring minds want to know.
 
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Do you guys freeze seals before you use them or does that just make the coating stiffer and make them harder to get in? I honestly can't remember what I've done in the past...
 
Do you guys freeze seals before you use them or does that just make the coating stiffer and make them harder to get in? I honestly can't remember what I've done in the past...
Only if it's a real fight to get on because of old stiff rubber, (think carb boots) when I'll use some rubber lube and heat, just warm room temperature for me.
 
XS Trader Name is of my own choosing. I was trained as a motorcycle mechanic under the old brit system -
5 years apprentice under a journey man + 2 college stints + government exam, Then I graduated
as a Aircraft engineer, then ran a MC speed shop that worked on everything along with my brother/partner
who was a Marine chief engineer who could run everything made from coal/steam to nuclear.
Sold the speed shop and went into being an importer/distributor from Japan.
Every distributor i ever met in Japan would visit castles and bars, I went to Factories, trading companies and OEM parts sub- suppliers.
Sold or have Known owners, purchase managers and technical people from most Distributors out there.
Smart guys were Tony Hall ( Halco ), Schell thuet, and Jerry Heiden ( Heiden Tuning Netherlands - Still running but almost retired )
Have sold hard parts to the UK, Canada, Germany, Holland, NZ, Australia, Japan and the scan countries.
I am old now and body is getting to be a mess but most marbles still intact. I am interested in All 60-80's bikes.
Yamaha is owned by Toyota as is Koyo Bearing, ART Pistons and most of the sub suppliers.
I am retired but would go back in with an ambitious partner who had some serious cash.
Note: To you guys wanting to DIY electronic ignitions - Factories who make these have NO,... NO .. knowledge .. I checked.
Factories get a blueprint, a phoney part number and No info on design. Design may be from Toyota.
 
Well guys, I joined this thread because I had some oil seepage. It had been driving me nuts. I, in my great xs650 wisdom determined that it was from the cam cover seals and gasket. Wrong, six seals in and an oem gasket and the definitive O ring from partzilla. The whole time it was the right intake valve tappet cover which I had hastily reinstalled after checking clearance before a major ride. My haste made waste...but I learned a lot.
I just finished a weeks worth of re surfacing both sides of the cam cover and the head...etc.
Still leaked today on a decent ride to Kankakee State Park. So we decided to ride west on 102 and the road closed. We went anyway and determined we could not pass the bridge. So then I had a Come to Jesus with the old XS and said, "Where the Fu#k are you leaking from? And then my keen observational skills took over and revealed that I had buggered the valve cover re install from weeks ago.
Jump in and make a sticky of the comments related to this one.
I spent a year futzing with a gas cap which resulted in numerous rewirings and ignition adjustments and carbs and jets and God only knows what.
So my advice...
Look for the simplest solution, not he obvious one.
It's Air, Fuel, Fire, and mechanical transference...with a little electrical thrown in...except for the firing part.
Be nice to one another. And if some obsessed XSer asks about a potentially catastrophic issue, look to the simplest and not to the obvious and help direct their obversataonal skills toward the simplest solution.
A gas cap vent and a buggered valve cap reinstall cost me some quality riding time.
...but I learned a lot.
Grace and Peace, All! Just waiting on the nest crisis.
 
As mentioned a few months back, that I replaced the 7mm cam seals with the 5mm's. Well, the left side began weeping badly. At closer inspection, with seal removed, there were scratches on the cam surface. This cam and head were extras when I purchased a 75 a few years back. Don't know what year it is, but it was better than my worn out 72 and the bent valve head from the 75.
Well any way, I got out the emery, 400 then 800 and polished it the best I could, but one scratch was more of a gouge. Well, not wanting to replace the cam, I cleaned it several times with brake clean. Dried it, warmed it up a bit and filled it in with a dab latex paint. Let it dry for several days and some heat, then 400 and 800 grit again, then pressed the 5mm seal in a little deeper as prescribed by you guys. If it fails, then I may just continue to change seals for the next 50K miles.
To anticipate, your comments, though, I thought about apoxy, but apoxy loosens up with heat. Any one who repairs golf clubs would know that. The latex paint should not be affected by any oil that might get on it. Even brake-clean won't remove properly dried latex, (water based), paint. After about 2K miles, no sign of a leak. Time will tell.
 
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Yep go the speedie sleeve. Mine been on for a few years now no leak from that pesky LH cover after many seals, cleaning cleaning cleaning... It can be a bit tricky to install.
Honestly if I do a rebuild I would speedie sleeve all bearing surfaces. My boat trailer hub had water ingress issues cleaned it up and found nasty grooves. Quick speedie sleeve and all fixed. I did set the axel speedi sleeve up in metal epoxy but never on engine components medium Loctite is all I would use. They are Stainless Steel so far superior to the carbon steel sealing surfaces so no seal grooves due to the hardness of it.
 
Well guys, I joined this thread because I had some oil seepage. It had been driving me nuts. I, in my great xs650 wisdom determined that it was from the cam cover seals and gasket. Wrong, six seals in and an oem gasket and the definitive O ring from partzilla. The whole time it was the right intake valve tappet cover which I had hastily reinstalled after checking clearance before a major ride. My haste made waste...but I learned a lot.
I just finished a weeks worth of re surfacing both sides of the cam cover and the head...etc.
Still leaked today on a decent ride to Kankakee State Park. So we decided to ride west on 102 and the road closed. We went anyway and determined we could not pass the bridge. So then I had a Come to Jesus with the old XS and said, "Where the Fu#k are you leaking from? And then my keen observational skills took over and revealed that I had buggered the valve cover re install from weeks ago.
Jump in and make a sticky of the comments related to this one.
I spent a year futzing with a gas cap which resulted in numerous rewirings and ignition adjustments and carbs and jets and God only knows what.
So my advice...
Look for the simplest solution, not he obvious one.
It's Air, Fuel, Fire, and mechanical transference...with a little electrical thrown in...except for the firing part.
Be nice to one another. And if some obsessed XSer asks about a potentially catastrophic issue, look to the simplest and not to the obvious and help direct their obversataonal skills toward the simplest solution.
A gas cap vent and a buggered valve cap reinstall cost me some quality riding time.
...but I learned a lot.
Grace and Peace, All! Just waiting on the nest crisis.
A scientific principle known as "Occam's razor" In this case gggGary's o-rings would have had you leak free in minutes....:whistle:
 
20191103_164815.jpg An update on the left side cam seal and the Latex paint crack filler. No leaks after about 10K miles. Yahoo!
 
I pretty much won on the tach drive, oil cooler line leaks on Madness, which mainly points up that cam shaft seals are next.
gloved up.jpg
Thanks for all the pointers here.
 
244_Shell_cam_covers.jpg
If a crank triggered ignition is used, it allows "Shell" type cam covers to be fitted, and there is not much need for cam seals anymore. I believe Hoos Racing and Jerry Heiden both offer those covers. I got a pair from Mule when he still offered them.
 
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Which seals do you refer to as there are 3 each side: camshaft oil seal, Oring and paper gasket? The oil seal on the shaft is necessary to stop oil passing through the bearings and out??
 
Did both sides, used the seals found in the ebay engine seal kit. 25x40x5 interestingly the two seals were from different makers... Other than the old gaskets being REALLY stuck on the housings (think they got embedded/bonded into the clear coat) it went smoothly. Used some WS2 on the lips before installing. Pamco with e-advance, so no issues with removing iggy partz. Will report back later if I get any leaks.
Pulled and checked the plugs cuz I've had two tanks in a row at over 60MPG and it was starting to worry me a bit. Not a plug chop just from after I got home last night. They looked fine lightly colored. Left may be using a bit of oil.
20210820_171916.jpg
 
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