Cam Chain wear test?

[dbbrian]

Thanks Motoman for the note on the original fasteners. I thought I needed the ones from the Vmax to use, made sure I bought one with them...duh.

Scott - I did your test - lined up the intake cam with dot at arrow. The exhaust is pretty damn close, so by that measure the chain is not too bad, and this is more about tensioner function. Good.

However, when I look at the timing position at the crank, I see it is way off.

Right? So I need to get the chain over a tooth ?

Intake


Exhaust


Timing

[3Phase]

Yeah, the mechanical timing is way off!

Resetting the timing is finicky but not too difficult and there are several ways to do it, just take your time.

I don't suppose you have a manual or even a PDF?

[dbbrian]

I have a manaul printed, and the PDF.

Previous comments suggested running condition would mean timing is not off.

So perhaps it is. Does that mean I will get MORE power

Looking at page 3-47, step 11, it says " With crankcase at the "t" mark, dots should be aligned with raised arrows....if not, disassembe the sprokets...repeat above procedures...

I think it is exactly 1 tooth off.

Brian

[3Phase]

Yes, you have to loosen the sprocket bolts to remove the sprockets.

Be careful, work slowly, follow the manual and you'll be fine.

[dbbrian]

Thanks Scott

BTW, I did check TDC by feel with a screwdriver in cyl 1. It came out exactly at the T mark.

Brian

[3Phase]

You're welcome, Brian, and have fun!

Next thing you know it'll be all timed and everything and you'll be zipping up and down the road with a huge grin plastered on your face.

[3Phase]

I had a thought, like a BB in a boxcar. It is physically possible the timing wheel is installed wrong.

Simple stuff to check first before you tear into the timing:

If you loosen that timing wheel bolt can you rotate the wheel on the end of the crankshaft? That would be caused by a missing or sheared mechanical advance locator pin.

Remove the bolt and wheel to see if it was installed wrong and then the bolt cranked to to hold it. If the wheel was installed 'off' then you can see new marks around the original factory hole.

[Bonz]

Thanks Scott

BTW, I did check TDC by feel with a screwdriver in cyl 1. It came out exactly at the T mark.

Brian

Good, that was something I suggested that I'm glad you did it. It makes me feel validated. LOL.

I would still put the acct in there because if you're not tight on the chain it can allow things to appear not lined up.

I've never done an XS but the ZRX 1200 is real similar in terms of having markings that lineup. Everything looks good and then as soon as the tensioner goes tight things change. That's how I ended up a tooth off, it looked good and everything lined up, but when that tensioner took the slack out it was not what I thought I was. It could work in reverse and make everything okay for you when you let that automatic tensioner extend for the first time. And rotate the engine in the correct direction.

[MPittma100]

Cam Timing

You might want to check to see if “T” is indeed at top dead center.

I have looked at a number of engines and have only seen one that was showing "dead nuts on" dot to dot alignment. All others were "close". Beware of the one tooth off theory especially if the engine is running well. Before moving the chain around the sprockets, be very sure of timing pointer indicator matching piston at TDC. TDC of piston needs to be verified rather than assuming pointer is accurate.

[Bonz]

Thanks Scott

BTW, I did check TDC by feel with a screwdriver in cyl 1. It came out exactly at the T mark.

Brian

He did verify TDC matches exactly with the pointer. Put an ACCT in there by the proper method, spin the engine a few times and see what you get for the marks. That is the next step as far as I'm concerned. Nothing is an exact science and if it runs great, the old adage is still true... The enemy of good is better. If it's running good trying to make it better only backslides your situation.

[dbbrian]

Thanks

Those recent post have me convinced. ACCT goes in first before I **** with a good running bike.

Waiting on the mail for my ACCT. I will report back when I get that step done.

Thanks guys, this forum is awesome. It is like having a bunch of buddies right here, helping me through..isolated or not. Way better than facebook BS

Brian

[Bonz]

Now that we've settled on that until the next step, Scott, you still have your 2018 117 inch Harley that your signature is showing?
That's a nice bike, I remember it from the Gunnison rally. You gave that bike some character stripes in that time you were out here!

[3Phase]

Yes I do still have my Harley. I ride different bikes according to how I feel at the time or what I'm going to be doing.

When the warranty is up in another few years on the Harley then I'll find an aftermarket tuner to remove the ridiculous 107 MPH speed limiter the factory programmed into the computer.

Columbo, my '80G, is almost finished and rebuilt again but my XJ1100 is the only running Yamaha right now and I need to find a new windshield for it.

[motoman]

Thanks Motoman for the note on the original fasteners. I thought I needed the ones from the Vmax to use, made sure I bought one with them...duh.

Scott - I did your test - lined up the intake cam with dot at arrow. The exhaust is pretty damn close, so by that measure the chain is not too bad, and this is more about tensioner function. Good.

However, when I look at the timing position at the crank, I see it is way off.

Right? So I need to get the chain over a tooth ?

Intake


Exhaust


Timing

Very welcome dbbrian.

[dbbrian]

Acct is installed

After a challening gasket removal, the new (used) ACCT is installed. Chain is now taunt.



Timing still looks off to me, but its hard to imagine I wouldn't have noticed the bike not running well if off by one tooth. But that is what it apears to be as I rotate the crank around, stop at dot alignment, the timing mark is as below... is that 15 deg. BTDC?

Not much better that with old CCT






Moving the crank around to the T mark appears to move the cam sproket about 1 tooth as I eyebell it dissapearing into the engine casing.

So now what? Is it possible the chain slipped a tooth and no performance noticable? I'm no expert, but thnik it would be noticed if the bike ran different.

Cams are reasonbley aligned, so would the chain have jumped a tooth at the crank sproket?

Brian