first bobber project

[Boneswig]

Yes could be camtiming. I don't know the history of the motor. I turned by hand so if the valves are bent least it wasn't by my hands. Could be why the starter is missing. Will strip the motor down during the week

[TopCatGr58]

Hey Bones,

Okay, the XS11's other weak link IS the cam chain tensioner! See this thread on info about different ways to address this weakness!

http://www.xs11.com/forum/showthread...nute+cam+chain

With the engine only turning a short distance, it does point to bent valves and lost cam/valve timing. The valves are difficult to come by, so would suggest NO MORE attempting to turn the engine, pull the valve cover/cams, and then the head for a better inspection. You won't be able to confirm the loss of valve timing with regards to being able to check the alignment of the timing dots due to the inability to rotate the engine/cams to the "T" pointer point of the timing plate. Hopefully you won't have any serious dents/indentations in the actual pistons!

However finding bent valves will be all of the confirmation of lost valve timing you'll need...and will almost always be due to the loss of tension of the Cam Tensioner which allows the chain to skip teeth. SO...then you can replace/MOD dependent on which is either easier or cheaper...whichever you prefer.

T.C.

[Boneswig]

Had brakefluid in the cylinders and it came loose. Will open the motor this week to have a look at what damage it has done. Will definitely do the camchain tensioner mod.

[Boneswig]

Ok so I made a mistake. I measured out the seat support for the springs, welded in the support and fitted the springs. Never took into consideration that the height measured was including springs. So need to remove the bracket and move it down. Got a nice set of "frog eye" headlights and found a tailight from a XJ. Fits snug behind the seat hiding the springs from the rear. We'll that's once I move my spring bracket. So moral of the story "tackweld, check, check again and not sure if I mentioned it, but CHECK if it is correct and THEN weld. I still have some time before my 8 week deadline is over. Itching to take her for a ride.

[TopCatGr58]

Hey Bones, that's great newsl that the engine broke loose. Now it points more towards rust in the cylinders from storage possibly outside, humidity getting into the cylinders via an open valve exhaust or intake. You may be able to save your self some work in not having to take the head off...but do take the valve cover off, and rotate the engine clockwise viewed from the left side...yes the engine rotates backwards...and then stop at the "T" mark, and then view the cams...the alignment dots should line up with the arrows on the cam bearing caps...and if so..or very close...like less than 1 tooth space, then the cams are still in time, and you probably haven't bent any valves. You'll want to check the valve clearances. Just be aware that with rust in the cylinders, you can also get some rust forming on the shaft of the valve that was depressed and exposed...and so it may not close fully. IF that's they case, you may want/need to pull the head afterall to perform both valve cleaning, lapping, and valve seal replacement. IF you pull the head you'll need a head gasket....they are expensive by themselves from Yamaha.....you can get a complete gasket kit with valve seals for just a bit more than the cost of an OEM head gasket.

But if the valves aren't stuck open, then you can do a compression test. You will probably find the values low ~ 80 or so psi, but hopefully not 0!
Then put some transmission fluid or if you have it...Marvel Mystery Oil into the cylinders and let it sit a few days to help soak into the rings because they may also be rusted and stuck. Then repeat the compression tests.

But folks have found low comps on a salvage engine, and then after running it several hundred miles, the rings reseated, scrubbed the cylinders, and the compression values came back up to within normal specs.

T.C.