Can’t Adjust timing, way too advanced

[BlackRabbit18]

Let my XS1 sit for about a month while I was waiting for parts. Buttoned everything up and went to kick and every other kick results in terrible kickbacks, will not start.

Went to check timing and as expected it was advanced… but WAY advanced like firing at 9’o clock! I have no clue what’s up and no amount of adjustment will bring it anywhere close. Any clue on what’s wrong? Thanks

 

[Kevin Werner]

Sounds like you need to go to step one... Find TDC with a screwdriver through the spark plug hole (approximate) and see where your timing marks are. Then (plugs still out)check your points timing as you turn the engine over by hand.

 

[BlackRabbit18]

Approximate TDC

Red mark indicates where right side points begin to open (when test light comes on)

 

[5twins]

I would check the advance unit. The locating pin for it in the cam may have fallen out and it could have moved. That would throw the timing way off.

 

[BlackRabbit18]

I would check the advance unit. The locating pin for it in the cam may have fallen out and it could have moved. That would throw the timing way off.

Will check that this weekend! Thanks

 

[BlackRabbit18]

I would check the advance unit. The locating pin for it in the cam may have fallen out and it could have moved. That would throw the timing way off.

pulled advance rod out and made sure all the dowels were aligned in the same direction, made sure cam dowel was installed and that the advance unit was working properly that all looked good. By adjusting the points gap I can get the timing line to 6 0 clock, but still nowhere close to where it should be. Any other thoughts?

 

[5twins]

Well, if the cam chain is really stretched out and the adjustment was allowed to become very loose, it may have jumped a tooth or more on the sprockets. The way to check for that is to put the engine at the TDC mark and check the location of that locating pin hole for the advance unit in the right end of the cam. If the chain is good and hasn't "jumped" any teeth, it should point straight up or straight down .....

 

[BlackRabbit18]

FML… that’s at tdc… I took the cam chain tensioner off to replace the gasket. The tensioner was off for a few weeks (covered) but bike def rolled around while it was out .

Now I’m guessing I need to pull the motor, take the head cover off, break the cam chain and set it correctly?

 

[5twins]

Well, you may be able to take the tensioner off again and "jump" it back. I'd try that first. If it won't work then yes, the motor will need to come out. You probably don't need to break the chain. If you slip the bearings off the end of the cam, that will give you the room to move the cam under the chain. But, if your chain is badly stretched, you probably should replace it anyway. You're going to run out of adjustment slot on the timing plate eventually, if you haven't already.

 

[jetmechmarty]

Yes, if the chain has a lot of slack, and it jumped that easily, you can likely remove the tensioner and rotate the cam to move a tooth on the crank.

Be advised, a new chain is almost banjo tight with the tensioner out.

If you buy a chain, call Michael at 650 Central. He may still have a deal on peanut chains. He’s also in California.

 

[BlackRabbit18]

Yes, if the chain has a lot of slack, and it jumped that easily, you can likely remove the tensioner and rotate the cam to move a tooth on the crank.

Be advised, a new chain is almost banjo tight with the tensioner out.

If you buy a chain, call Michael at 650 Central. He may still have a deal on peanut chains. He’s also in California.

What’s a good way to tell if I need a new cam chain? I replaced all the top end gaskets a few months ago, and at that point I broke the cam chain and put in a new master link (chain looked good and bike only has 9,000 miles)

 

[BlackRabbit18]

Well, you may be able to take the tensioner off again and "jump" it back. I'd try that first. If it won't work then yes, the motor will need to come out. You probably don't need to break the chain. If you slip the bearings off the end of the cam, that will give you the room to move the cam under the chain. But, if your chain is badly stretched, you probably should replace it anyway. You're going to run out of adjustment slot on the timing plate eventually, if you haven't already.

I have no clue how I would jump it back, I don’t even know how it jumped forward lol. I would love to try

 

[jetmechmarty]

What’s a good way to tell if I need a new cam chain?

If you can realign the chain as I described, I believe it's too loose. I'm just guessing, but my hunch is you mistimed it when you broke it apart. You'll have to take the top off to reset it. It sounds to me like you're going to have increased intimacy with this motorcycle. It's awesome to ride a motorcycle that you're confident you can fix whatever goes wrong.

 

[BlackRabbit18]

If you can realign the chain as I described, I believe it's too loose. I'm just guessing, but my hunch is you mistimed it when you broke it apart. You'll have to take the top off to reset it. It sounds to me like you're going to have increased intimacy with this motorcycle. It's awesome to ride a motorcycle that you're confident you can fix whatever goes wrong.

Oh it ran and timed perfectly after I broke and re did the chain. Even did a 10 hour ride on it. Problems started when I removed the tensioner 3 months later “to fix a small leak” sigh lol

 

[5twins]

To try and jump the chain back, I would put a wrench on the crank (rotor nut) then try turning the cam in the opposite direction. I wouldn't do that with the little M6 nuts on the ends of the cam but rather by grabbing the points cam with some vice grips (protect it of course, with a rag or sheet rubber). Of course, have the tensioner out or very loose.

 

[BlackRabbit18]

To try and jump the chain back, I would put a wrench on the crank (rotor nut) then try turning the cam in the opposite direction. I wouldn't do that with the little M6 nuts on the ends of the cam but rather by grabbing the points cam with some vice grips (protect it of course, with a rag or sheet rubber). Of course, have the tensioner out or very loose.

Thanks for the help everyone! I wound up just spending the last 2 days dropping the motor removing the head and adjusting the cam into the correct position. Just got most of the bike put back together and timed correctly, and she started right up!

 

[arcticXS]

To try and jump the chain back, I would put a wrench on the crank (rotor nut) then try turning the cam in the opposite direction. I wouldn't do that with the little M6 nuts on the ends of the cam but rather by grabbing the points cam with some vice grips (protect it of course, with a rag or sheet rubber). Of course, have the tensioner out or very loose.

Won't grabbing the points cam put a load on advance shaft and advance mechanism? I would be a bit sceptical about that.....