ACCT Installed Wrong?

[Rasputin]

I have a link to the post I was making while dealing with a similar issue.
http://www.xs11.com/forum/showthread.php?t=31788 at about the 24th or 25th post will show you pics. The thread itself will show how I had low compression and other problems, sort of anyways. At least the pics show the arrows and dots and timing plate that you need to know. I am sure someone will chime in with better info, The search function will help you find what you need if you can find the right effing words to put in (which I never can).

[crazy steve]

Here's the condensed version....http://www.xs11.com/forum/showthread...223#post357223

[IanDMacDonald]

Excellent posts gentlemen!!! I took the morning off to go out there and make sure everything is right. Right now I am dealing with a dead battery issue that I never had until just yesterday. The one time the engine tried starting before the battery died, it backfired, which made me wonder if the timing was off. I shall post results within an hour or two.

[IanDMacDonald]

okay, looks like I did some major boo boo's when I attempted to put that ACCT on. Look like the Exhaust cam is off a tooth, and they are both off completely based off the timing mark. I sent Rasputin a PM asking for a step-by-step on how to get those marks to re-align, but, I'm happy for anyone willing to devote a little time to a dummies guide to fixing screw-up.

Do I just simply rotate the crank to the "T" mark and then unfasten all of the cam caps and rotate the cams to match up with the timing marks? I'm not that savvy with cams. Never had the bad luck of having to adjust them.

https://www.dropbox.com/sh/a3gy1eulrbkjblg/0e39-L6s9v

[IanDMacDonald]

I spoke too soon . . .

I just went back out there and instead put the plate on the "T" mark and this is what I found (second two pics):

https://www.dropbox.com/sh/a3gy1eulrbkjblg/0e39-L6s9v

Looks like the Exhaust is spot-on, and the Intake is off by a tooth.

[crazy steve]

You'll have to pull the ACCT out again, then you have choices in how you re-time the cam. You might be able to get enough slack in the chain to simply disengage the chain from the intake sprocket and turn it so it's right. Or remove the bolts holding the sprocket to the cam, then move the sprocket one tooth, turn the cam, then reassemble. I wouldn't pull the cam caps, that won't give you enough 'play' to do this (or at least it didn't work for me...).

[jetmechmarty]

I am not sure it's off a tooth. It might be, but it looks to me like it might just be a well worn chain. Mine looked something like that before I replaced it.

[Rasputin]

It is for sure off by one tooth. That is exactly what happens when you do an incorrect change of a CCT/ACCT. In the post I made earlier with the link and the one Steve put in, you will find the answers to how to fix it. The manual does show a lot as well and I will see if I can find the page numbers in one of mine. Which manual are you using?

[shousey440]

spare head

Let me know if you need the spare head. If the valves are bent, the ones in this spare head are ok. New yam valves are expensive. Is that the yellow bike you're working on?

[IanDMacDonald]

Thanks Scott and Steve. I'm thinking about going out there now (it's 1:15A) and seeing if I can get that cam back in-place. I think what I'll do is follow Steve's post regarding his valve adjustment. I'll put it on the "T" mark, loosen the sprocket bolts, rotate the engine again and get it back where the marks are, remove the CCT, rotate the sprocket a tooth, then re-attach the CCT, re-bolt the sprocket in-place, and hope this did the trick.

[WMarshy]

Thanks Scott and Steve. I'm thinking about going out there now (it's 1:15A) and seeing if I can get that cam back in-place. I think what I'll do is follow Steve's post regarding his valve adjustment. I'll put it on the "T" mark, loosen the sprocket bolts, rotate the engine again and get it back where the marks are, remove the CCT, rotate the sprocket a tooth, then re-attach the CCT, re-bolt the sprocket in-place, and hope this did the trick.

Sorry in advance b/c I didnt read the entire post but be care full about rotating the engine with the cam bolts out of the cam sprockets. If you rotate it far enough you will make contact with one of the open valves.

With the ACCT out you will have enough slack in the chain to "jump" a tooth on the exhaust sprocket. Just roll the slack up and over one tooth then rotate the cam forward slightly to take up the slack, put the ACCT back in and give it a few rotations and check you marks. This process can be easily use to advance the cams toward the front of the bike but not so well the other direction.

[IanDMacDonald]

Yes sir gentlemen, it's 4:26a, and I am just coming inside from the garage. I have good news to report. By the grace of God, I ended up getting the marks in-sync with the timing plate. It took me a couple of hours of trial and error. Every time I got them together, I would be past the "T" mark by an inch. So, what I ended up doing was cheating a little, and started the timing plate a little early and used the CCT, that way when I did my first crank after setting the cams, they would begin to turn in-sync with the "T" mark on the timing plate. After that, I did a compression check and was looking at 120 across each cylinder with the exception of #2, which I saw 150 in. This was done with the plugs in. After that, I threw the tank on and it started-up instantly. I have to run to Auto Zone tomorrow and pick-up some more of that Permatex "The Right Stuff". It's only good for one use, and I threw on the equivalent of three or four gaskets worth every time I took the cover off. I'm going to check the sync on the carbs again just to make sure they are not off.

Thank you for all of your help in dealing with this crisis, lol. Once again, everybody's input has saved my butt, and my bike.
Something is bothering me though. It sounds like the bike is different. Cannot tell if it sounds like one of the cylinders is not firing all the way (they are all hot), but, it's different sounding, you know what I mean? Like, it sounds like the exhaust note is is being restricted. Not sure if that's a bent valve or not, but, I guess I'll know soon enough.

[DGXSER]

First, I hope you did check the gap on all the valves when you were finished with the timing adjustment. That is the best way to check for a bent valve. IF one is bent, the gap will show as MUCH bigger than it should be typically.

If your compression numbers are that good, and it is firing on all four (all four getting hot) then I would say you do not have a bent valve. Probably just need to synch and tune the carbs.

[IanDMacDonald]

First, I definitely did not check the valve clearances like I should have following the timing of the cams. Damn!!! Second, I got the bike started this morning and it sounded "okay", but not great. I took it for a short ride and it sounded just a tee bit off. You know how you know it sounds just a little bit off, but everyone else would not know the difference? Well, I could tell that something was off just a little. So, got it back home and pulled everything off and ran a compression test on cylinder number one. Shot to 90, then 120, then 0. Hmm. Tried cylinder number two, 0. Three and four were 0 too. Hmm. My buddy suggests that it could be just a timing issue. I doubt that. I hear a tapping sound coming from cylinder number one. So, I assume that's a bent valve. Scott (PO) has another head that he's willing to give me from a parts bike. Should I just swap the other head on?

[DGXSER]

Hmmm sounds very interesting. I would pull the valve cover back off and recheck the timing. If your timing is off enough to lose all compression like that you would almost definitely bend valves. Check the valve clearances, and check the timing marks.

A little while back, TRBig had a similar issue, every time he checked the timing after fixing it, it would be off a tooth again. And yes, he bent some valves. I forget exactly what he found, but essentially the chain was skipping a tooth on the crank shaft, sort of looped an extra link down there IIRC.

If you find you have bent valves, and the head is off the same bike. that would be the simplest solution. By same bike I mean 80-81 versus 78-79 engines. The intake valve sizes and cams were changed in 80, as well as piston design. 79 cams are different than 78, but the heads will work with no real issues.