Cam Gears Install Question

[BillyRok]

I had 2 valves that were on the low end of the clearance tolerance so I swapped out shims, following the tech tip http://www.xs11.com/forum/showthread.php?t=35434

I'm not understanding what this means...

Note the little 'points' by the second pair of bolt holes......as shown in close-up here. These holes must be on the same 'side' of the cam as the dots or your cam timing will be off.

When my dots lined up with the marks like so --
[IMG][/IMG]


--the bolt holes WITHOUT the little points were at the top of the cam gears like this --[IMG][/IMG]

Bending a valve is not my goal but don't I just put the gears back on the same way they were when I took them off? I've never had them off before and the bike ran fine so I'm assuming it must have been right? This statement is what has me confused:

These holes must be on the same 'side' of the cam as the dots or your cam timing will be off.

Can somebody clear this up for me please?

Oh, one other question. I popped out the other 6 shims that didn't need swapping just to record the sizes so I'll know what's there already for the next time I need to do this. Would all 4 intake shims and all 4 exhaust shims have been the same size originally when the bike was made? Just curious because mine varied from 275 to 310. With over 34K on the bike I'm sure somebody has done this before.

[BA80]

You see the raised or outlines around the bolt holes on the gear and the one with the "point" pointing up?

That has to be facing the side (or end) of the cam with the alignment dots. The holes are slightly offset to one side and if the gear is installed the wrong way it throws the cam timing off.

Let me go out and look at the cams I have out and be sure what I just posted is true.

[BA80]

Correction.....the side with the little arrow goes on the OPPOSITE side from the dot but goes in the bolt hole that lines up the closest to the dots.

Clear as mud?

[TopCatGr58]

Hey Greg and Billy,

Regrettably this photo he posted in the tech tip doesn't show the sprocket teeth on the bottom where his thumb is. But Billy if you look closely as the top end, you can see that the little nipple pattern around the bolt hole is NOT in the center of the sprocket teeth notch. I think part of the terminology problem is what is being said about the sprocket's position. I don't think the nipple END of the sprocket needs to line up with the cam alignment dots....but just that the side of the sprocket that you can see the nipple pattern needs to be facing the direction of the cam alignment dot. Think about it, you could flip the sprocket around so that the nipple was facing away from this view in the photo....and the position of the sprocket teeth would be a few degrees different in rotation position which could/would place/position the cam a few degrees out of time with the crank.



I remember taking the sprockets off of my cams when I did my top end job, and I didn't KNOW about the nipples, and so I don't KNOW if mine are in the correct position or not? But I've run it for 10 years and 10+K miles, and haven't blown up the motor. SO...having the sprocket flipped around wouldn't necessarily cause a bent valve, but could reduce the overall performance, fuel mileage/power of the engine.

Hopefully Greg will be able to confirm whether his nipples are in the same position location as the alignment dots, or maybe they are not, but are at least FACING the part of the cam that has the alignment dots !?

T.C.

[BA80]

Yeah, I wasn't sure either but I have 2 heads on the shelf out there that have not had the cams or gears removed since I took them off. The engines are seized and I just cut the chain to remove them.

What I posted the second time is correct.

[TopCatGr58]

Okay, what Greg said in his last post. I just RE-Looked at the photos....they were a little confusing, because one view of the sprocket is from the side of the cam dots,



this other view is from the OTHER SIDE of the sprocket away from the cam dots...but on the side that you can see the nipples! SO....the nipples DO face AWAY from the end of the cam that has the alignment dots.

BUT, the tech tip says to first see the alignment dots....THEN rotate the cam 180 degrees so you don't see the dots and remove those sprocket bolts....Then he says rotate the cam again so you can AGAIN see the alignment dots, and THEN he shows the sprockets and the nipples....so and states about the nipples aligning with the same position as the alignment dots.

Looks like Steve might need to edit the tip with some clarification notations!?

T.C.

[MPittma100]

Too Late

It is too late now, but there is no need to take the cam gears loose to adjust the valves. IMHO it is more (unnecessary) work.

Taking the gears loose is reserved for cam swap, valve job, or timing chain replacement.

My 2 cents.

Mike

[BA80]

I agree Mike. I personally don't see a good reason for even loosening the cams, but that's just me. I've never had a problem with the tool.

Maybe if ALL the shims needed to be changed but not the normal 1 or 2.

[MPittma100]

Agree

I agree Mike. I personally don't see a good reason for even loosening the cams, but that's just me. I've never had a problem with the tool.

Maybe if ALL the shims needed to be changed but not the normal 1 or 2.

I've done several with the special tool. It just takes patience and a supply of shims to adjust the valves. There aren't any short cuts.

[natemoen]

I had my gears on wrong when I pit my head together and I had piston/valve contact. Didn't damage anything since I was rotating by hand though.

[BillyRok]

I didn't have the tool so I guess I did it the hard way, I won't make that mistake again.
But back to the gears...when I had the crank on "T" the cam dots lined up with the marks as I'm standing on the left side of the bike. When I look from the right side of the bike I see the gears and bolt holes without the nipples. So with the cams in this position, the dots are visible on the top side of the cam but the holes with the nipples are near the bottom of the gears down inside the head and are not visible. The only other way to install the gears would be to rotate them 180 degrees to bring the nipple holes up to the top of the gears so they are visible at the same time as the dots are. So if I'm understanding you, you should never be able to see both the dots and holes with nipples at the same time, when one is up the other should be down...Correct??

[natemoen]

So if I'm understanding you, you should never be able to see both the dots and holes with nipples at the same time, when one is up the other should be down...Correct??

No, you should see both the dots and the holes with the nipples at the same time.

You need to unbolt the cam gears and rotate them 180 degrees so that the nipples are up when the dots are up.

[BillyRok]

Nate if you look at he pics I first posted you can see dots on top and holes without nipples on top. That is the way it was when I took the valve cover off. Are you telling me that the cam gears have been on the cams 180 degrees off from where they are supposed to be??? The bike would still run that way?

[BA80]

Ok Billy......pictures......


With the timing dots lined up......



The other side of the gears should look like this.....

[natemoen]

Nate if you look at he pics I first posted you can see dots on top and holes without nipples on top. That is the way it was when I took the valve cover off. Are you telling me that the cam gears have been on the cams 180 degrees off from where they are supposed to be??? The bike would still run that way?

Yes, I am telling you that the gears were on wrong before.