Where did you get your gasket?  My recent purchase was at Partzilla and it doesn’t have the metal.  I need to compare are my part # to your part # when I get back home.

Sorry I threw that out there about a leak from above.  I know you know this better than me!

Decided to look it up before getting back home.

Your gasket part # ends in B20.  My gasket # ends in B11 for my model K5.  Apparently that’s the difference. B20 is the good one, but same price?

And what the heck is the difference between all the different models k5-k9?  There are other model difference for other year bikes and I’ve always attributed it to California models or European models or something like that.

Makes me want to order a B20 gasket and overlay it onto a B11 gasket…. Is there an extra hole or passage or something?

Sorry for hijacking your post!

Better hope it isn’t the bababase gasket ! But that makes a mess quick and you can usually see it.

DragBikeMike wrote on 09/16/24 at 12:30:38:


The cylinder, head and head cover are completely dry and clean.  I have removed the fuel tank and looked them over repeatedly.  I have stuck a new Q-tip in every fin, nook and cranny of the head looking for any signs of oil.  The 8mm nut under the intake is clean and dry.

The oil droplets seem to be coming from the top of the right side clutch cover.  That place leaks oil and the wind catches it and blows it behind the cylinder.

I am going to try replacing the clutch cover with a clutch cover that hasn't been struck by a disintegrating clutch cam and see what happens.  If the leak persists I will remove the oil pump overdrive gears and see if the leak goes away.

I got a replacement side cover to try - it needs to be cleaned up and polished before it is mounted.  It won't happen for a couple of weeks as we are busy doing other stuff right now......no time to play motorcycle for a while.

Wow - it is hard to believe that it has been 11 months since I have posted an update.

I got a replacement side cover, stripped the clear coat, sanded out the corroded areas and then buffed it up to a nice shine.  I had to drill the bypass hole and install the jet to bypass the oil to compensate for the oil pump overdrive gear set, install the clutch lever pieces, etc.  I also did a bit of work to make the clutch push rod with a bit more radius at the outer end.....as it was seating well into the Sneezy clutch cam well and the rod for the lever was moving in/out a bit when the engine was running. (Stock push rod lengths don't work as the clutch has been modified to use DR650 clutch parts and an extra metal and fiber plate).

I then washed the bike and got the engine spotless....so I could identify any remaining leaks.

The last few days I finally got around to riding the bike.  I started out with a small ride around the country block - the bike got warm but not up to full operating temperature.  I rode pretty slowly and never went more than 3,000 rpm in 2nd gear - I didn't want wind blowing any leaking oil into places it didn't originate from.  I inspected the bike carefully and I could not see any oil leaks.

The next day I went on a bit longer ride - and kept speeds below 30 mph.  I carefully inspected the bike and did not see any oil leaks anywhere.

Yesterday I went on a longer ride and got the bike fully up to temperature.  I was up to 50mph a few times - I likely rode about 15 miles.  When I got home and the bike cooled down, I found where the oil leak is.  Leaking oil is incredibly hard to see on the low gloss black - but after 10 months of sitting in the garage a light layer of dust had built up on the engine - and it easily showed where oil had flowed and turned the dust to a darker color.  There was a small amount of oil that had dripped out of the cylinder bolt/nut under the exhaust port...and a bit of oil coming out of the head gasket directly above that bolt/nut.  The oil is likely seeping through the head gasket layers.

I did not have any way to properly torque the nut to the 16.5-19.5 Foot Pounds - so I had been using a box end wrench and did my best guess as to when it was tight enough.  This method seemed to work for the last 16,000 miles since I did the 95mm Wiseco piston - but maybe I guessed wrong this time and got it too loose.

I made a tool to allow me to get the proper torque, and I removed both the front and rear nuts and cleaned them up.  I used the high temperature thread sealant that DragBikeMike recommended, and I torqued them up.  The sealant requires 72 hours to fully cure - so I will go for a ride on Sunday and see what happens.  If the leak is not gone - I will remove the head cover and try re-torquing all the cylinder studs.  If that doesn't work - I will remove the head and install a new head gasket.  (The head was resurface and the cylinder checked for flatness prior to the assembly - the issue should not be from anything being warped).

PS (Sorry about the reflection of my plaid jammies in the clutch cover).

My goodness that is a pretty engine.  Very nice indeed.

As I recall, you opened up your exhaust port.  My experience with that particular stud (the 8mm just under the exhaust) is that when you open up the exhaust port that stud pulls out of the aluminum head.  At first, it seems to come loose, and you retighten and ride and it's loose again, and you retighten and its loose again.  Over & over until eventually it quits coming loose.  It quits coming loose because the shoulder on the stud contacts the metal gasket and now it stays tight.

The cylinder head is like a beam with a big hole in the center.  When the hole is small (stock port), the beam is much stronger so the 9mm studs on the front-right and front-left impart more force across the center.  That span, right to left is much longer than the span front-to-rear, so Suzuki installed the 8mm studs under the exhaust and intake ports.  Put big holes (Intake & exhaust ports) in the right-to-left span and the beam gets weaker.  Make the holes bigger (porting) and it gets even weaker.  The intake doesn't exhibit a problem because it's cool as a cucumber, but the exhaust is extremely hot and the strength of the aluminum is much, much less when up to operating temperature (I'm guessing 450 degrees on the interior surface of the exhaust port).  So, you stress up the 8mm stud, get it up to temp, and the internal threads yield a bit.  Now the nut is loose.  Tighten the nut, get it up to temp again, and the internal threads yield some more.  It continues until the shoulder on the stud hits the metal gasket.   Now the fastener isn't restraining anything.

Once I started making the special insert that is installed from inside of the port (top-to-bottom), that problem went completely away.  That thing is never loose on my bike, and when I remove the head, the insert is well away from the gasket surface.  It is never proud.

Those MLS gaskets are much more forgiving than copper gaskets.  If you try to fix it with a copper gasket, I think the leak will get worse, unless you do a special insert for the 8mm stud.

This old post provides details on the 8mm stud mod.

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1665791582

You absolutely have to fix the leak.  Your bike is too pretty to have any sort of leak.