another cam chain/ valve adj. issue

Just got my bike back from the dealer today. Was having that loose chain noise (started at about 60k) and seemed to be getting louder now at 76k. Tried replacing just the tensioner first but it skipped a tooth on the sprocket. Bike would not idle and ran pretty rough... oops. Well since it was in the shop already I had a new chain, sprockets, gaskets, etc. overnighted so we could do chain replacement and valve check.

Now....no more noise, bike sounds like new, idles smooth but as someone else posted just doesn't feel as strong. Roll-ons in 2nd are just o.k. not the usual front end gets light smooth rush of power as before. Something is a little off but it wouldn't be noticeable if you're not familiar with an FJR. (valves were all in spec)

My question is if the exhaust or intake cam were off by a tooth what would the symptoms be? I know if the chain skips a tooth on the crank it's pretty obvious but is it a really subtle difference if it's off on one of the others. Is there a way to diagnose without going back into the motor? The mechanic that did the work is very good as is the dealer but s..t happens.

If I take it back to re-check the work and everything is in the proper position I'm out about $300. so I'd like to be a little more convinced that the cams may be an issue. I,m anal about my ride (you guys know what I mean) and this kind of thing makes me crazy!

I don't know if a compression test would indicate a cam timing error or not, it might. I'm not willing to open up my motor and screw-up the timing to find out.

For certain a substantially lower compression test result immediately following a valve adjust, would be real reason for concern.

Most FJRs will test in the 225-230 lb. range.

There's no other indicator I can think of for a cam being one tooth off, short of pulling the valve cover and checking.

Looks like I need to open a new business called, AfterBirth - We cleanup what they screw up!

Wouldn't even one tooth off have a significant change how the FJR runs?

SkooterG said:

Wouldn't even one tooth off have a significant change how the FJR runs?

Click to expand...

Absolutely yes! I was trying to think of some "measured indicator" that could be used to force a dealer to re-do the adjustment.

The most likely timing mistake is the exhaust cam. The intake cam is pretty easy to see and I would hope no 2-cent mechanic would miss the intake cam and crank sprocket timing marks. The exhaust could be misread by anyone working against the clock.

One tooth off on the exhaust cam might not be enough to make the motor run BAD, but it sure would be noticeable.

This is why... even though it took me 6 days to do it... I did my own valve check. Not only do I KNOW the job was done right, and no plastic was broken, I now know how to take the plastic off, all the tricks for getting the valve cover off, and how to deal with the cooling system.

Heck, last time I went to the dealer, they couldn't even put the piddly little plastics back on the DL-650 properly. I shudder at the amount of sheared tabs, wrongly-overlapped joins, cracked holes and lost fasteners I'd get on the FJR. Oh and they put the front tire on backwards too.

Update on my timing issue or non-issue according to the dealer

After reading and re-reading all the related posts here and after talking to all the mechs at the dealer the general consensus seems to be that if any of the sprockets are off by even 1 tooth there is a very noticeable difference in performance especially in the lower rpm range, idle or off-idle.

I personally rode my bike after the CCT install was off by one and it was pretty obvious. Bike wouldn't hold idle and ran a little rough at higher rpm. As i mentioned in my orig. post I overnighted sprockets, chain gaskets etc. which were then installed.

Bike now idles strong and is smooth at all rpm. it's just not as smooth as I remember. The power delivery is linear it's just not the rush that I'm used to. Rode it all day today and I just can't duplicate that old rush that we all love. (this is all so subjective, I know). The bike "feels" down about 10% on the butt-meter but that 10% is where the fun is!

A mis-aligned tooth on a sprocket appears to cause a more dramatic effect than I'm experiencing. Is it possible the new sprockets on the cams can be installed off a degree or two? All the marks line up but the sprockets are rotated on the camshaft? This is all academic as I have no practical experience in this area.

What say the more enlightened??

There was another post where the same symptoms were reported, the mechanic eventually took it all apart and discovered that one cam had jumped a tooth,

From what you are describing it sure sounds like the timing is off....

As I mentioned is another thread, the symptoms of the cam chain being timed wrong would depend entirely on which sprocket was off and in which direction. Being off in one direction by one tooth would advance the cam, in the other it would retard it. Is it just the intake camshaft (unlikely) or just the exhaust (quite likely) or did the crank sprocket skip one tooth (effectively advancing or retarding both intake and exhaust valves)?

The symptoms would vary for each condition. Though the exhaust being +/- one tooth seems to be the easiest mistake to make.

Well, I decided to take my bike back to the dealer tomorrow to check the timing. If there is something amiss the dealer fixes it - no charge. If it all looks good - I pay. I honestly hope there is something here thats not right so I have 2 questions.

1. How long should it take very competent mech. to remove the valve cover and check the timing

2. Besides checking the marks on all the sprockets for alignment, is there anything else we should be looking for? I plan to eyewitness this (in a friendly way)

Thankyou for looking at this. It looks like 4-5 days of great weather at the Blueridge coming up. Like to leave Saturday with a good running machine!

In addition to Jeff's suggestion about checking compression, doing an intake vacuum comparison (taken as you might during a TB sync) between the suspect bike and a known good one would most likely tell the tale.

"Yamaha says that at idle the FJR should pull 25cm of vacuum"

-R

As an additional note:

I had new exhaust and intake sprockets installed (along with chain and tensioner) during the last valve check. Could these be put on somewhat mis-aligned or is that very not likely?

I having the dealer re-check their work tomorrow and want to be able to have ideas on what to look for in addition to the timing marks

ANY suggestions are welcome and appreciated!

bhkfjr said:

As an additional note:
I had new exhaust and intake sprockets installed (along with chain and tensioner) during the last valve check. Could these be put on somewhat mis-aligned or is that very not likely?

I having the dealer re-check their work tomorrow and want to be able to have ideas on what to look for in addition to the timing marks

ANY suggestions are welcome and appreciated!

Click to expand...

Yes, indeed, the sprockets can be mounted incorrectly.

First, you must remember that both cams and sprockets are identical. Same part numbers for both intake and exhaust cams and sprockets. What makes them work is totally dependent on correct sprocket alignment when installed on the cams. Take a look at this picture:



On the intake cam (left side of picture) the sprocket MUST be bolted on to the cam so the sprocket bolts (circled) are bolted next to the "I" symbols on the sprockets. If they're bolted 180 degrees off, it doesn't matter, as long as the bolts that hold the sprocket on the cam are bolted through the "I" hole in the sprocket.

The only difference for the exhaust cam sproket is the bolt must go through the hole in the sprocket (circled) marked "E".

The orientation of the sprockets on the cams determines which cam is an intake cam and which is an exhaust cam.

Once the sprockets are installed correctly, depending on their intake or exhaust designation, then having the cams "in time" with the crankshaft is next AND most important.



With the "T" mark on the timing rotor at the right-side end of the crankshaft lined up with the mark on the block (the spot where the crankcase splits) then the cams must be aligned where their timing marks align PERFECTLY with the top surface of the cylinder head.



Notice in the above picture, you can plainly see one of the bolts holding the sprocket on the (left) intake cam and the bolt is right next to the "I" mark, which is just above and to the left of the bolt head. On the (right) exhaust cam, the bolt is right next to the"E" mark, just above and to the right.

The cams are "in time" with the crankshaft when:

1 - The "T" mark on the crankshaft rotor is aligned perfectly with the split in the crankcase (picture #2)

2 - The "— —"marks on the intake sprocket are perfectly parallel with the cylinder head (picture #3)

3 - The "<— —>" marks on the exhaust sprocket are perfectly parallel with the cylinder head (picture #3), AND

4 - The holes in the intake and exhaust cams line up with the casting marks on the cam holddown bracket (picture below, #4)



BTW, WHEN the holes line up with the casting marks, the cam lobes on cylinder #1 should be pointing to 10 o'clock and 2 o'clock, as viewed from the sprocket ends of the cams.

Here's the problem with timing the cams.....it's VERY easy to get one cam a tooth out of time with the other cam. Even with my motor out of the bike, with nothing in the way, and taking the UTMOST care installing a new camchain and tensioner on my motor, here's what happened the first time I locked everything down:



Even taking care and using surgical precision, I timed the intake cam one tooth off. Had to release the tensioner, pull the chain off the intake cam and turn the cam one tooth clockwise to get it back in time.

Doing this job with the motor in the frame is difficult and triple checking all the facets of 1 thru 4 I detailed above is critical for nominal operation AND to prevent valve damage. A tech "on the clock" might get sloppy, lazy, or both, and not have things just so.

Hope this helps.

'Howie

Wow, Howie, very impressive, seriously, even I could understand it and believe I could be successful...well with the engine out :yahoo:

Take my advice, change careers and give vehicle and mechanical advice on a call in show on the Radio

BTW, as of today, the goal of all involved is to have me on the road back home on Isabella next Thur and is very doable unless there's some unforseen circumstances

End of day today will accomplish new used shock, new fork springs, new tires, new racing alum valve stems, new steering head bearings and wheel bearings, all pivot points cleaned and greased :yahoo: :clapping: :yahoo:

Patriot said:

Wow, Howie, very impressive, seriously, even I could understand it and believe I could be successful...well with the engine out :yahoo:
Take my advice, change careers and give vehicle and mechanical advice on a call in show on the Radio

Click to expand...

There's an old joke in my business. Goes kinda like this:

"Why did I get into radio? Easy. I'm too lazy to work....and too nervous to steal."

Pretty much explains a radio career.

BTW, as of today, the goal of all involved is to have me on the road back home on Isabella next Thur and is very doable unless there's some unforseen circumstances
End of day today will accomplish new used shock, new fork springs, new tires, new racing alum valve stems, new steering head bearings and wheel bearings, all pivot points cleaned and greased :yahoo: :clapping: :yahoo:

Click to expand...

Damned if I may beat you. I'm so close.....a couple of hours Saturday, a couple Sunday, and I should be able to have someone at the house taking pictures of me driving down the road.

'Howie

Thankyou Howie, exactly what I was looking for. Now I know how to think about this and what to look for.and how to talk about it somewhat intelligently.

It appears that if the sprockets were installed incorrectly it would be a major league goof and the bike wouldn't run.

It also appears that when you lock the cams down, any slack in the chain could rotate a sprocket out of time and that this is the point at which to double check that all is still lined up.

With the cam lobes at 10 and 2 and all sprockets in time do the holes in the cams automatically line up with the marks in the casing or is that a fine tuning thing done at some other point in the procedure??

for a ride the first day...I want video of ya going down a twisty road naked <right, "twisty" & "naked"> :dribble:

don't go naked on THE first ride...the bike might explode and you should wear a catchers cup and as much armor and nomex as possible :clapping:

bhkfjr said:

Thankyou Howie, exactly what I was looking for. Now I know how to think about this and what to look for.and how to talk about it somewhat intelligently.
It appears that if the sprockets were installed incorrectly it would be a major league goof and the bike wouldn't run.

Click to expand...

Not to mention wreck the valves.

It also appears that when you lock the cams down, any slack in the chain could rotate a sprocket out of time and that this is the point at which to double check that all is still lined up.

Click to expand...

Absolutely. It's after the cam holders are bolted down and the chain under tension, THAT'S when the timing must be checked. You can't check it any other way.

With the cam lobes at 10 and 2 and all sprockets in time do the holes in the cams automatically line up with the marks in the casing or is that a fine tuning thing done at some other point in the procedure??

Click to expand...

They line up when the marks on the sprockets line up with the cylinder head. The holes in the cams are "double-check" marks, because it's possible to line up the sprockets to the head with the #1 cylinder cam lobes pointing the wrong way! The "10" and "2" are approximations, too.

Thanks and double thanks again Howie. I actually feel so much better now!

Now if I could just figure out how my bike lost "half a tooths" worth of performance after the valve check, chain and tensioner install. I can't justify tearing the bike apart looking for such a small anomaly unless I know just where to look. Your tutorial has been most helpful

bhkfjr said:

Thanks and double thanks again Howie. I actually feel so much better now!
Now if I could just figure out how my bike lost "half a tooths" worth of performance after the valve check, chain and tensioner install. I can't justify tearing the bike apart looking for such a small anomaly unless I know just where to look. Your tutorial has been most helpful

Click to expand...

Until you check it out, there's no guarantee that a timing problem is what your problem is. And if it IS a timing problem, it's not a "small anomaly" as you put it. Obviously, you haven't crashed any valves yet.....you'd know if you did.....but mis-timed valves is NOT a good thing, especialy considering the FJR is an "interference" motor, that is, the clearance between pistons and valves at TDC is close enough to hit if the timing is off too much. Ask me how I know.

Good luck discovering the problem.

'Howie