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stupid mechanic questions- no laughing! haha

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Ok, so I need to put rings in my 94 250L once it gets too cold to ride. I know it needs rings because it's blowing oil out of the valve inspection and valve cover gaskets, and its losing oil without any other visible leaks.

I'm no stranger to bikes- i've done frame off restos on 3. Problem is, they were all 70's two strokes. I haven't messed with valves or more specifically timing chains. My worry is pulling the head and when I re-assemble it the timing is going to be off.

So, what can I do? I haven't been able to locate a *free* service manual to help me with this, even the library doesn't have one. I'm assuming I'll have to find TDC after I replace the rings, jug, and head, but how do I know where to align the cam? Should I put the motor at TDC before taking it apart and mark the cam/crankshafts? Sorry i'm an idiot.

Also... the bike has 10,000 miles. Not really hard miles, mostly street. At what point to do I need to think about lapping valves? Replacing the cam chain or tensioner? Replacing valve stem seals? I figure as long as i'm in there I might as well do it if it's close to being time.

Thanks!

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Having a manual is the quickest thing since al the procedure is there (saves time):busted: But while you find it I hope I can help.

First thing we gotta know is we have two TDC here, TDC compression and TDC exhaust, for Disassemble and specially re-assemble we want to be at TDC compression. So remove the inspection caps at the head cover and also at the bottom left side of the engine. There youll see a T, to find it rotate the crank always counter clockwise, once you center the T with the indicator mark above (its hard to keep it there so keep checking constantly) move the rocker arms if all of them have a slight up and down movement, if so, we are at TDC Compression, if the intake valves are loose and the ex valves are tight then we are at TDC Exhaust time, if so turn it one more revolution until you find the proper TDC.

For reassemble Locate the T at the crank, and then lay the cam with its lobes pointing down this give us the compression time.

Note: During disassemble release tension and the chain tensioner by pushing the wedge that its at the front side of the engine and while doing it use some pliers to pull up the wedge that is at the rear side, have an assistant put a paper clip through the small hole to retain the tensioner's pressure.

Sorry if :bonk::busted:

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Also while its apart!! Get the valves checked and lapped or cleaned up and do the valve seals while your at it. A new cam chain and tensionser guides would only make sense while its apart!

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cool, thanks guys! I'll see how much cash I have when I get it apart and how many parts I can afford. I've been doing some reading and plan on doing the valve seals while I'm in there, heck they could be bad too. I was going to check for leaking valves by inverting the head and filling with starting fluid to see if there's any leaks.

Thanks again!

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I would also upgrade to the Xr R cam and do on overbore. The stock carb does work ok if you are willing to spend a little time tinkering? If not go R carb as well or a mikuni pumper etc. Just my thoughts.

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Oh buy the way! My Avatar has my 94L going through a very large puddle that was about 3ft deep but had 3inch of Ice frozen across the top! Feet got a little wet! LOL>

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Hey, also as an aside, you may want to verify the crankcase vent isn't plugged. I can't see it blowing oil out of the valve check without some serious blow-by. Just a thought! That is a great pic btw.

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