timing help and info

kiser1991

XS650 Enthusiast
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hey guys im making progress on my new xs650 after cleaning the gas tank and gleaning the carbs new fuel lines and getting her back togther i fired her up for the last night and the bike ran real rough. im going to work on syncing the carbs later but in the meantime i want to go ahead and get everything timed. let me start by saying i have slim to no mechanical experience but the info i have been getting on here makes things very easy to follow. heres what i have going on, when i cranked it up it fired up immediately then just died. it will not idle with choke on or off. it will run extremely rough while giving it gas but ever rough. i have had 3 other xs650 and all 3 had the same style pipes on them but this one was hella loud. it would shoot flames out of the exhaust when revved up. i could keep it alive by finessing the throttle so i took it down the road. while driving it ti wasnt getting power when you give it throttle. it would build up speed extremely slow. when the clutch was in tho it would rev up just like my other bikes, really fast. but in gear and driving it there would be a massive lag. i didnt feel anything slipping tho. im going to work on timing today and any insight would be much appreciated. i will include a few pics. i have no idea if these parts are stock or after market and not sure if that that affects how i need to time things.
 

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thats the video i will be using to do mine but do you think after market parts chhangeany anything? im doing static
 
It looks like the P.O. installed an aftermarket PMA charging system but failed to make new timing marks. Without timing marks, you won't be able to set the timing. It appears your inept P.O. has struck again, lol.
 
You'll need to make timing marks. You'll need 3 - TDC, idle timing (15°BTDC), and full advance timing (40°BTDC). Hugh's Handbuilt, who sells aftermarket PMA kits, includes a sticker for the case with the timing marks on it. If you have that then all you need to do is find TDC accurately and mark the flywheel. Here is a picture of the Hughs sticker. From it, you might be able to get a pretty good idea where the timing marks need to be. Notice the "Fire" mark (idle timing) aligns with the right side of the drain notch in the case. What would be best is if someone with a sticker could give you measurements between the marks .....

GBmaijd.jpg


There are a couple ways to accurately find TDC but they involve some special tools you probably don't have (piston stop, degree wheel). Being that this is your 4th 650 and you still know nothing about them, all this may be a bit beyond your capabilities. But, I can walk you through the easiest method, accurately finding TDC using a piston stop, if you like.
 
You'll need to make timing marks. You'll need 3 - TDC, idle timing (15°BTDC), and full advance timing (40°BTDC). Hugh's Handbuilt, who sells aftermarket PMA kits, includes a sticker for the case with the timing marks on it. If you have that then all you need to do is find TDC accurately and mark the flywheel. Here is a picture of the Hughs sticker. From it, you might be able to get a pretty good idea where the timing marks need to be. Notice the "Fire" mark (idle timing) aligns with the right side of the drain notch in the case. What would be best is if someone with a sticker could give you measurements between the marks .....

GBmaijd.jpg


There are a couple ways to accurately find TDC but they involve some special tools you probably don't have (piston stop, degree wheel). Being that this is your 4th 650 and you still know nothing about them, all this may be a bit beyond your capabilities. But, I can walk you through the easiest method, accurately finding TDC using a piston stop, if you like.

sir there would be nothing i would like more for you to walk me through this!
 
Yes, that would be a big help. Then all you need to do is accurately find TDC and put a mark on your flywheel in line with the "TDC" mark on the sticker. That's all you need is the one mark on the flywheel. It will align with the other timing marks on the sticker depending on the RPMs. You use the "TDC" mark with the motor off, for when you're setting your valves.
 
so let me get this right when i get a piston stop i need to put the piston at the very top, the mark the fly wheel with the tdc. that all? and is that just to be able to assemble it back to the right point? also what are rhe other 2 marks on the sticker used for?
 
A piston stop is a tool that screws into the spark plug hole and extends down into the cylinder a little bit. It is usually adjustable so you can set how far it sticks into the cylinder. You can make your own by gutting an old spark plug and threading a bolt through it. You start by approximately finding TDC by looking in the spark plug hole and watching for the piston to come up as high as it can while slowly turning the engine over by hand. When you see the piston through the spark plug hole, you can stick a drinking straw in there and watch that rise then start to fall as you're slowly turning the motor over. Work the piston back and forth (up and down) until you find the approximate TDC. Then back the piston down about a half inch and install your piston stop. Adjust it so it contacts and stops the piston from rising any farther. Move the piston up and down several times, bumping it against the stop, to make sure it's up to it and making good contact. Make a temporary mark on the side tab of the cover and a temporary mark on the flywheel in line with it .....

FnpwnOo.jpg


Now back the piston down away from the stop and continue to rotate the motor slowly until the piston comes back up and contacts the piston stop again. Don't move or adjust the piston stop at all, leave it exactly where it is. Make a second temporary mark on the flywheel like so .....

tIJLIbq.jpg


Now carefully measure halfway between your 2 temporary marks. This will be exact TDC. Remove your piston stop and align the halfway mark to your temporary mark on the side cover. Then make a permanent mark on the flywheel for TDC in line with the TDC mark on your sticker .....

L3khalp.jpg


You can now remove all your temporary marks so you end up with just the one permanent mark left on your flywheel. The TDC mark will be used with the engine off for setting your valves. The "Fire" and "Advance" marks will be used for setting your timing. This can be done "statically" (motor off) or with the motor running using a timing light.
 
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Judging by how rough you say the bike is running, it's very likely your timing is off. Without timing marks, there would have been no way for the P.O. to set it exactly.
 
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