Technique to adjust valve timing

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st4gary

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Did my third valve check just before Xmas (along with CCT replacement and block-off plates). After 90K miles I had to finally make a shim adjustment (#1 intake). After commuting this week on the bike, and searching through the forum comparing notes, I have a strong feeling that I slipped a tooth on the crank gear of the timing chain. Poor, hunting idle, poor off the line performance and a very noticeable mi-range dip. After surviving the end of the year 2013 FJR buying frenzy, I decided to do the major service on the 2004 I've had since nearly new, refresh the Wilbers again and keep the old girl for another year or two. But I have to deal with my possible screw up. I'm pulling the bike apart tonight to verify the timing via the marks on the end of the cam gears (vs. the dam holes in the cam which apparently didn't do me much good the first time around) and will know if timing is the cause of my problems.

I'm looking for first had experience in making this adjustment. I've been thinking about it and I was hoping to not to have to pull the cams and somehow making up that 'tooth' down at the crank gear. Anyone that's gotten into this mess in the past, I'd appreciate thoughts on the technique/procedure you used to make it right. This would be pretty easy with the motor sitting on the bench, but that's not the case.

Regards,

Gary

 
Gary,

I did the shim adjustment recently, but managed to not get out of timing. Did you have the chain zip tied to the cam shaft sprockets during the adjustment? If so then the only place that could/would be off would be at the crankshaft sprocket. I know that when I was re-tensioning my chain after the adjustment, the chain wanted to jump back a tooth on the bottom, and I had to force it into the right cog. I knew where the correct timing was because I had marked the edge of the first camshaft caps with a sharpie before un-tensioning the CCT.

At this point, the only way that you will know when you are fully back in time will be to pull the valve cover again (sorry). There are some index marks on the frame side of the two cam sprockets but they are almost impossible to see with the engine in the frame. Aligning the dots with the cam cap arrows should work, but also make 100% sure of the T- mark lining up with the crack in the two halves of the cases at the crank.

Also, with the T- mark lined up, when you view the engine from the left side, the #1 cams should be equally splayed left and right. Hope that helps.

 
Hi Fred,

Thanks for the reply. Yes, I had the cams/chain zip-tied and the chain zip tied around the crank gear during the valve adjustment. When I finished the valve adjustment I removed the zip ties and rotated the engine a few times manually and rechecked the intake valves (the cam that I removed). I think where I got into trouble is when I then replaced the CCT. I remember hearing an extra click and was immediately worried I skipped a tooth on the crank. But after futzing quite awhile looking at the camshaft home and camshaft cap arrow I finally talked myself into thinking all was ok. I should have gone your route of marking the camshaft with a sharpie. I had read your article but I think I was feeling safe and happy after getting the valve adjusted and just got slopping doing the CCT.

If I find that the timing's off tonight, a buddy's going to come over tomorrow and hopefully two heads will produce a better result this time. Four hands and elbows should fit down between the engine and frame just fine! :)

Gary

 
Well the good news I guess is that the cams are both 1 tooth off so I must have skipped a tooth on the crank gear replacing the CCT. Will have to figure out tomorrow how to adjust it. I think I just might loosed the chain and with a second set of hands rotate the engine counter-clockwise 1 tooth to get things back in time. I know you're not 'supposed' to go in that direction but it's the slightest amount of rotation.

Gary

 
BS to not going 'the other direction'. Don't know where that mis-info came from. At least that's what my tech says and he's been wrenching bikes for at least 40 years.

 
The key to the valve adjustment is prevention. Before you remove the cams, rotate everything so the timing marks on the cam sprockets are aligned per FSM, crankshaft too. Aligning the dots and arrows wasn't precise enough for me..... You can see these by gunsighting between the frame and sprockets with a good flashlight. Zip tie the chain at the crank sprocket too. You can rotate the engine "backwards" when the chain is disengaged at the crank, the reason for clockwise is when everything's connected. Rotating clockwise takes up all the slack chain on the front side and should give you more accurate indications on the timing mark positions.

 
^ this.

If you rotate the crank CCW the crankshaft sprocket will be pulling against the back side of the timing chain loop and may compress the CCT putting slack on the front side. And if that happens skipping teeth is a good likelihood.

FWIW, when I was fighting my chain to get it back on in correct alignment, that is exactly the direction it was wanting to go, so I also had to turn the crankshaft bolt CCW a little.

 
Well Fred, last time I did a valve check with my tech we cranked CCW many a time with nary a problem.

 
Well Fred, last time I did a valve check with my tech we cranked CCW many a time with nary a problem.
SkooterG I agree with you; however, some have had issues. I also didn't believe the CCT change would have a skipped tooth either, some have had it, so I'd tie up the chain on CCT's and I would go CW or CCW, but with the caution something could slip. I don't worry about though.

 
Regardless of the how the timing got off .... the valve timing is correct now and all it right with the world! Just popped off the ignitor rotor and with a second set of hands gently bumped the engine CCW using the rear wheel to relieve the tensions in the cam chain (with the CCT retracted and cam chain tie-wrapped to the cams) and was able to adjust for one tooth on the crank gear. The camshaft holes and cam cap arrows lined up perfectly. I could tell the minute I started it up as I had previous cranked on the idle adjust to keep in running when out of time, now it was idling at nearly 2k RPM with the cams back in time. Re-adjusted the idle and it sounded great. On the commute this morning I had a smile back on my face. My buddy was disappointed as thit probably means I won't be replacing the old girl this year. Another year to two maybe as the bike's all set with the valves/CCT and Wilber refresh done, there's nothing to do but ride now!

Thanks for comments.

Regards,

Gary

 
It's a little late, but if you haven't done the sharpie trick you can use a flashlight and a small inspection mirror inserted next to the frame to verify the cam position. DAMHIK.

 
I haven't done a valve shim job yet but was wondering about using a paint marker like this to mark the chain and sprockets instead of using zip ties. You would just align the paint marks on final assembly.

6410016.jpg


 
I haven't done a valve shim job yet but was wondering about using a paint marker like this to mark the chain and sprockets instead of using zip ties. You would just align the paint marks on final assembly.
To add to what Fred said just above, marking the chain and sprockets isn't a "bad" idea, but it won't do **** preventing the dreaded "one-tooth-slip" that so many have suffered.

Zip-tie all three sprockets and proceed with care. Preventing the slip is the key, not marking the chain, because you don't really need marks on the chain...the chain is not the issue, it's the position of the cams in relation to each other AND the crank sprocket. Marking the chain won't stop it from slipping a tooth...a couple of zip-ties around the chain at the crank shaft sprocket and one each at the camshaft sprockets WILL stop it from slipping. Then you don't have to align anything,.

 
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