Another dumb one?????

[Whip]

When I did the valves at LimeCreek's Tech Day's eddd bumped the back wheel in 6th gear till the springs were loose. I watched the valves and springs while he did the bumping. It ain't any fun by myself. Goin back and forth from the back wheel to the valves in 100 degree heat in the garage ain't any fun.

 

Soooooooooo

 

What tricks are there to finding TDC?????

 

Stick somethin somewhere and bump the starter??????

[Boffin]

When I do this on my own, I remove the alternator belt cover and use the nut on the end of the crank to turn the motor (16mm). I have a chopstick in the plug hole and watch it come out. As it gets close to fully out (practice!) I look in the timimng window on the RH side flywheel cover for "OT" to come into view.

 

Andy

[tcausey]

Stick a chopstick or dowel into the spark plug hole and rotate the rear wheel until it's at it's outermost point and then go wiggle the rocker arms to see if they're both loose.

[Jerry Duke]

I like using a plastic straw instead, but other than that Andy's suggestion works best for me.

[Richard_D]

Very good instructions here. I found a grommet and a plug at ace hardware and cut a hole in my alternator cover so I don't have to take it off to turn the nut. http://elmi.de/valve-dummies.pdf

[Joe Frickin' Friday]

When I do this on my own, I remove the alternator belt cover and use the nut on the end of the crank to turn the motor (16mm).

 

Just to clarify: if you're turning the crank via the alt belt pulley, turn it clockwise (as you look at it from the front of the bike).

 

As an alternative to the chopstick/sparkplug trick for finding TDC, since you already have the valve cover off, you can do the following:

 

-As you crank the engine over, watch the valves. There will be a period during which they aren't moving (this is the compression and expansion/power strokes), then the exhaust valves open (now you're into the exhaust stroke), then they close while the intake valves open (now you're into the intake stroke), and then the intake valves close (and now you're back on the compression stroke.

 

-Once the intake valves close and stop moving, give the crankshaft another 1/4-1/2 turn (3/8-turn is spot-on, but there's plenty of margin for error, see below).

 

The engine should be somewhere close to TDC at this point. Being EXACTLY at TDC is not required: the cam lobes are ground such that if the CRANKshaft is anywhere within +- 90 degrees of TDC, the valves are fully closed.

 

You can verify that you're close enough to TDC by examining the cam chain sprocket, which has arrows stamped onto its face. If the crank is within +- 90 degrees of TDC, then the arrow on the cam sprocket face will be within +-45 degrees of horizontal. Visually, anyone can identify when a line is within a couple of degrees of horizontal, so this is an easy check to do.

 

On my 1100 I always did the rear-wheel bump thing, avoiding the back-and-forth bullshit by just watching the valves as described above. Once the intake valves closed I could feel the resistance of compression as I continued to rotate the engine (not with bumping, but with a steady pull on the wheel); once the resistance suddenly disappeared I knew I had hit TDC, and I stopped pulling. Always ended up with the cam sprocket arrows within a few degrees of horizontal, ready for valve check.

 

Having said all that, a 6K maintenance event is a fine time to check the state of one's alternator belt, especially once the belt has 18K+ miles on it. It's probably wise to pull the alt belt cover for a peek, in which case you might as well use that pulley (instead of the rear wheel) for turning the crankshaft.

[Whip]

When I do this on my own, I remove the alternator belt cover and use the nut on the end of the crank to turn the motor (16mm). I have a chopstick in the plug hole and watch it come out. As it gets close to fully out (practice!) I look in the timimng window on the RH side flywheel cover for "OT" to come into view.

 

Andy

 

What window, where????

[Whip]

On my 1100 I always did the rear-wheel bump thing, avoiding the back-and-forth bullshit by just watching the valves as described above. Once the intake valves closed I could feel the resistance of compression as I continued to rotate the engine (not with bumping, but with a steady pull on the wheel); once the resistance suddenly disappeared I knew I had hit TDC, and I stopped pulling. Always ended up with the cam sprocket arrows within a few degrees of horizontal, ready for valve check

 

That may take some practice, but it sounds reasonable.

 

I have 18K on it now, so I guess I'll check out the ALT belt while I'm at it. What am I looking for???? Cracks, frayed edges, irregular wear patterns. That kinda stuff????

 

How easy is it to just replace it????

 

On the GS it's very easy to get to the cover.

 

 

 

[SAAB93driver]

I turn mine over by turning the crank at the pulley - I figure it is good to check the belt at each service anyway. The first time I did it I just put a paint mark on the pulley and crank case when I got to TDC. Now I just use the match mark every time to get it to TDC.

[eddd]

You could train Monty or Neumann to watch the valves and bark when you've reached TDC.

 

Or another thought...

 

Just use the stick in the cylinder trick I showed you and consider the crawling around to double check if the valves are loose a good form of exercise. It'll help keep you young and limber.

[eddd]

Alternator belt is easy to replace. You mentioned all the things to look for. At 18K you shouldn't have anything to worry about. Bring one to Torrey and we can do it in 15 minutes.

[philbytx]

Whip,

Just did a 6k on LeRoy this week...Powertrain oil changes, clutch adjustment, valves and TBS!

 

I thought you were going to call me to arrange bringing your GS down here to help you with all this stuff!

 

You not speaking to any Brit's because we let the Lockerbie bomber go or what

 

 

[Richard_D]

If you look at the link I sent you , you will see the little hole you need to look in for the OT. It's on the right side of the engine with a little black plug covering it.

[Polo]

When I do this on my own, I remove the alternator belt cover and use the nut on the end of the crank to turn the motor (16mm). I have a chopstick in the plug hole and watch it come out. As it gets close to fully out (practice!) I look in the timimng window on the RH side flywheel cover for "OT" to come into view.

 

Andy

 

What window, where????

 

I would not bother with the window. The arrows on the sprokets are quite reliable. Mitch's take on the absence of resistance is right. It doesn't take much to rotate the wheel, I do it by pushing with my shoe once I've reached the point of resistance.

 

My son lives in SA, just tell me when, and I'll come help you (show/teach you), I'll kill two birds w/same rock and go visit him as well.

[Ken H.]

I would not bother with the window. The arrows on the sprokets are quite reliable. Mitch's take on the absence of resistance is right.

Yes, and the cam’s profile is so wide accuracy in being spot on TDC is not critical.

 

FWIW, I use the chop stick in the plug hole and bump the starter method. (Both plugs out of course so it doesn’t fire.)

 

[Sellis]

I would not bother with the window. The arrows on the sprokets are quite reliable. Mitch's take on the absence of resistance is right.

Yes, and the cam’s profile is so wide accuracy in being spot on TDC is not critical.

 

FWIW, I use the chop stick in the plug hole and bump the starter method. (Both plugs out of course so it doesn’t fire.)

 

I basically do the same thing, sitting on the floor with the bike in 6th gear, bump the rear wheel and watch the valves looking for the compression stroke, when I'm on the compression stroke, I stick a long thin screw driver in the plug hole, and when I get the piston to the top, I'm close enough!

 

Steve

[Whip]

I would not bother with the window. The arrows on the sprokets are quite reliable. Mitch's take on the absence of resistance is right.

Yes, and the cam’s profile is so wide accuracy in being spot on TDC is not critical.

 

FWIW, I use the chop stick in the plug hole and bump the starter method. (Both plugs out of course so it doesn’t fire.)

 

Can I use the starter with the kickstand down......it seems to crank, but not fire???????

[T__]

When I did the valves at LimeCreek's Tech Day's eddd bumped the back wheel in 6th gear till the springs were loose. I watched the valves and springs while he did the bumping. It ain't any fun by myself. Goin back and forth from the back wheel to the valves in 100 degree heat in the garage ain't any fun.

 

Soooooooooo

 

What tricks are there to finding TDC?????

 

Stick somethin somewhere and bump the starter??????

 

Whip, no need to make a big deal of finding TDC compression on the oihead..

Just remove the valve covers,, then remove the spark plugs so the engine turns over easily,, then put the trans in high gear,, then rotate the rear wheel in the FORWARD direction until the cam chain sprocket arrows are facing straight out.. (that will leave one side or the other at TDC compression)

 

Then adjust the side that has all the valves up (none depressed)..

 

Then use the rear wheel (rotate forward direction only) & rotate the engine 1 full revolution until the other cam sprocket arrows are facing out (if in doubt mark the sprocket arrows that were out with paint or marker then make sure those arrows are now pointing in)..

 

Then adjust the other side (all valves up)..

 

You can easily see the cam sprocket arrows from the rear while turning the rear wheel..

 

 

 

 

Twisty

[Ken H.]

I would not bother with the window. The arrows on the sprokets are quite reliable. Mitch's take on the absence of resistance is right.

Yes, and the cam’s profile is so wide accuracy in being spot on TDC is not critical.

 

FWIW, I use the chop stick in the plug hole and bump the starter method. (Both plugs out of course so it doesn’t fire.)

 

Can I use the starter with the kickstand down......it seems to crank, but not fire???????

 

Crank is all you need. We're talking about a very short bump of the stater. Basically just a tap of the button.