Tore into the Engine today.

2389 Views 23 Replies 9 Participants Last post by Randall-in-Mpls, Mar 3, 2011

JWink

Discussion Starter · Feb 26, 2011

Well I finally got back out into the barn to tear apart my engine. Good news I got the rear cover off so I could take a look at the cam chain and stator.

Bad news cam chain is eating up the bolt so something must be bad and the stator is pretty dark in color.

I have the triple bypass document saved on my other computer so I have an idea of what all I need.

The question is what all should I be looking for when I am checking it out? I have never really understood how you tell if the cam chain is bad but this one has quite a bit of play in it so I think I need to start replacing parts.

I know I can do all this work myself it's just a little discouraging because I really thought all would be well. I didn't have any noises or anything odd at all. Plus having never done any engine work on a motorcycle like this I feel a little in over my head.

Here are some pictures of the damage.

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1 - 20 of 24 Posts

Shep

· #2 · Feb 26, 2011

Just consider it a 40k service.Most have us have or will come up against this lack of maintenance.As a matter of course if the Cam chain adjuster slot shows less than half left you may as well change the Cam-chain if you have the time and money.

The picture on here was BlindStitch's(Don) I think and he caught it in time,

http://www.pdsrecording.site90.com/cxgl500/noises.htm

If there were no copper flecks in the oil you should be ok.If the bike had no bad knocking before the strip you should also be ok.

What you need to do is make sure before re-construction that all metal debris is removed.As this is not a full strip down to the crank I use a car power washer or jet garden hose to flush the engine with some washing up liquid to degrease.I use it on,"Fan" and carefully for the rear case.I then high pressure air blow it dry as I have a small compressor.If you don't have one some friendly local bike shops/tyre places may let you use theirs or even a Hair-dryer/Hot Air blower can warm the engine up to stop parts getting rust on them and there's no harm spraying parts after a wash/dry with some WD40 type stuff as a temp anti-moisture film whilst you work on the engine.

As for the stator the thing is electro-mechanical parts have a life expectancy of between zero and infinity.No one can say how long a device may stay working or fail.If the Stator passes the tests on here

http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=8&t=30

http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=8&t=298

and you had no relevant charging problems re-use at your discretion.

HTH

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Blindstitch

· #3 · Feb 27, 2011

Yep. I caught mine at the right time. Consider myself lucky. It's usual maintenance.

Reg in Bristol

· #4 · Feb 27, 2011

I cant quite see in the second pic but take a look at the relationship between the

can chain tension bolt and the arm it secures

the arm has an elongated hole and as a chain wears/stretches the bolt will be nearer the top

of this hole than the bottom.

If its at the very top the chain is truly knackered !

Another quick test is to try and pick up the chain at the very top of the

cam shaft sprocket

A worn chain will be quite sloppy on the sprocket while a new one wont lift much.

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kingston73

· #5 · Feb 27, 2011

Here are a couple comparison pictures for you. From what I can see your engine block and bolt aren't too bad, and that is definitely from your cam chain so you'll need to replace it. If you didn't have the chewed up engine block, you'd have to look at how much travel is available in the tensioner slot. Like shep said, you can't really tell much by looking at the stator, unless you can see any burnt or frayed wires. These are from mine a couple years ago, the last one is my stator that has been fine the whole time I've owned the bike, and is original as far as I know:

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81custom

· #6 · Feb 27, 2011

While you are in the rear case, may as well replace the starter clutch components or at least measure the spring lengths, if they are shorter than specified - replace the items needed, save some more heartache if you have to take the motor out again to replace this..

Cam chain, guides if you can get them, water pump seal, new o'rings around water pump, and on the adjuster nut if yours is not an automatic adjuster.

it isn't too hard to do...just a bit fiddly, take your time, and check, recheck each step of the way.

JWink

Discussion Starter · #7 · Feb 27, 2011

I will just start looking for new bits. I had planned on doing this all eventually but didn't really want to do it right now. Don't really have to much money to spare but it will be worth it I suppose.

I do have another question, when I pulled the rear cover off the gear shift shaft was still stuck in the rear cover, I popped it out before I pulled it all the way off but it seemed like it might have stretched that spring out, so I might need to replace that while I have the cover off. When I put it back on it the pice with the teeth on it seems to go farther back than the pice that i assume it locks into. Any thoughts? Maybe i will need a picture of it, not the easiest thing to describe I guess.

81custom

· #8 · Feb 27, 2011

there should be a shim washer under the selector shaft going to the main case, you need this washer.

the spring even if stretched - I did the same - just cut it down a bit and reconnect it, make sure you have a good loop in it, so it won't come off.or buy another spring, have it all sitting together in the crankcase before mounting the rear cover over it - when you button it up - make sure you can select all gears before putting motor back in frame.

Randall-in-Mpls

· #9 · Feb 27, 2011

kingston73` said:
From what I can see your engine block and bolt aren't too bad, and that is definitely from your cam chain so you'll need to replace it.

Not necessarily true. Cam chain wear on the engine case can just as easily be caused by a maladjusted chain as by a stretched chain. Mine had at least as much damage as Wink's, and when properly tensioned, it still had more than half the adjustment range left.

To check it properly, set the left cylinder on TDC on the compression stroke (all the valves should be closed.) Loosen the adjustment bolt, make sure the arm moves to take up any slack, and re-tighten. (This is where it should be when you adjust it with every oil change.) To the degree that there's more of the elongated hole showing above the bolt than below, your chain has that much of it's useful life remaining.

R

Cobram

· #10 · Feb 27, 2011

That stator doesn't look bad at all. If there are no cracks in the lacquer or burn marks and it was working, you might want to leave it alone. Mine looked about the same, I had a replacement ready, but decided to let sleeping dogs lay and didn't molest it:

I'd venture to say that the cam chain "bite", in varying degrees, is present on 99% of the CX's out there. Mine was a bit chewed too, the cam chain was meticulously adjusted since new, the original style tensioner rail didn't have a reinforcement buffer in the middle like the updated ones do, even when properly tensioned they would still leave enough slack in the chain to buzz cut the crankshaft cap.

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Randall-in-Mpls

· #11 · Feb 27, 2011

Cobram said:
That stator doesn't look bad at all.

I think that was Kingston's stator, in pics he posted for comparison. We haven't seen Wink's.

R

JWink

Discussion Starter · #12 · Feb 28, 2011

I will have to get back out in the shop and take another look. It seemed when i took the cover off that the adjuster bolt was loose. I didn't get to ride the bike but maybe 150 miles since I got it late in the summer. I the PO did some screwy stuff with it, I don't think he was all that mechanically inclined. I don't think I ever checked on the bolt. I should be able to get back out into he shop tomorrow and see what is going on.

Randall-in-Mpls

· #13 · Feb 28, 2011

JWink said:
It seemed when i took the cover off that the adjuster bolt was loose. I didn't get to ride the bike but maybe 150 miles since I got it late in the summer.

If it was running without the adjustment bolt tightened, that would explain the wear on the case. Check the tensioner blades carefully, since they'd have been moving around quite a lot.

Remember, the tension needs to be set with the left piston at TDC on the compression stroke, so all the slack in the chain will be on the right side where the adjuster can take it up.

R

JWink

Discussion Starter · #14 · Feb 28, 2011

I just went out and took a look at it. I had the left cylinder at top dead center, where i couldn't move the rocker arms at all. Is that the compression stroke?

The nut was loose, but the adjuster wouldn't move at all. I tapped the end of the bolt, like most people say to do if your adjusting it in the bike. Didn't help. I actually had to push the adjuster over. It seemed like i had it pushed over as far as i could, and their was still a bit of room on the tensioner slot. It seemed like it could still grind up the case and bolt. I pushed on the chain with a screw driver and i think it could still contact the case and bolt.

Randall-in-Mpls

· #15 · Feb 28, 2011

JWink said:
I just went out and took a look at it. I had the left cylinder at top dead center, where i couldn't move the rocker arms at all. Is that the compression stroke?

On the compression stroke, you should be able to spin both of the pushrods. When there's a valve open, the pushrod is loaded and won't spin.

The nut was loose, but the adjuster wouldn't move at all. I tapped the end of the bolt, like most people say to do if your adjusting it in the bike. Didn't help. I actually had to push the adjuster over.

With the locking bolt loose, pull the adjuster outward against the spring to verify that it moves freely. Without the spring, the tensioner blade should tend to push the adjuster arm up. The spring pulls it down to warp the tensioner against the chain and take up the slack.

R

TREV2010

· #16 · Mar 1, 2011

What would you like to know, just finished restoring mine and the exact same damage to the casing, rear guide broke and never tensioned the cam in 70 000km...

Oh and alot more damage I found when I had the parts all laid out, the engine was totally stripped.

Have two different workshop manuals and took me a year to rebuild the motor only with OEM parts from all over the world. Also did the whole repaint....etc.......total restoration, not a rebuild.

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Randall-in-Mpls

· #17 · Mar 1, 2011

TREV2010 said:
...never tensioned the cam in 70 000km...

Ouch! Any pics to satisfy our morbid curiosity?

...took me a year to rebuild the motor only with OEM parts from all over the world.

Did you manage to find a NOS crank bearing holder? It seems to be extremely rare to find a used one that doesn't have at least a little wear on it.

R

JWink

Discussion Starter · #18 · Mar 2, 2011

Well yesterday I got to spend some more time working on the engine. I got the left cylinder at TDC and loosened up the adjuster nut. I pulled up on the tensioner to get everything working free and it moved back into position. When it is properly tensioned should the chain move at all? I could move it with a screw driver and make it hit the spot of wear. IDK if that means anything or not.

And the spring on the gear shift part, is that supposed to be tight coils or loose pulled apart coils? When I pulled the case off all that part pulled out too so I am still figuring out how it all fits back together.

Here is a picture of the tensioner slot when it is fully tensioned.

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kingston73

· #19 · Mar 2, 2011

That's still got some life left in it, maybe a little less than 1/2 way, but since you've gone this far I'd just go ahead and replace the chain anyway. That little slot in the tensioner will be above the tension bolt on a brand new chain. Also while you're in there don't forget to replace the oil seal behind the waterpump.

JWink

Discussion Starter · #20 · Mar 2, 2011

Yeah I figure at this point I might as well replace it all.

I just got a big box of parts yesterday with the WP oil seal, rear cover gasket, shifter seal, and a bunch of other stuff. Now I just need to order a cam chain and tensioner. I looked at a triple bypass thread the other day and it seems most of the cam chain specific stuff on the list is not available anymore. Would I be okay with just a chain and tensioner?

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