Best location to ty-wrap cam chain on crank?

dcarver · Apr 17, 2019

OK. Naomi's (2013) cams need to come out. It's been more than 30 seconds since I lifted cams in the 2006 (KrZy8) and now I are cornfused.

When I lifted KrZy8 cams, the dowel pin for the rear tensioner came out. As such, I ty-wrapped like this... On the inside of the tensioner. And, later, I slipped a tooth, IIRC.

Looking at Yamafitters CCT replacement thread, he ty-wrapped like this... - around each tensioner.

My question is - If both tensioners get ty-wrapped per Yamafitter, is there adequate chain slack to lift the cams?

What's the best location to ty-wrap to ensure adequate slack and yet not slip a tooth?

Thanks,

dCarver

RossKean · Apr 17, 2019

Fred W did a nice write-up a few years ago...

https://www.fjrforum.com/forum//index.php/topic/149508-valve-shimming-look-like-my-luck-has-run-out/?hl=%2Bvalve+%2Bcheck&do=findComment&comment=1020583

SkooterG · Apr 17, 2019

I've never ty-wrapped the chain to the crank sprocket. I've used a socket - I believe 12mm, between the guide and left side of the case to keep it from slacking and slipping. I learned that method from someone else here that had a photo posted in some thread.

SkooterG · Apr 18, 2019

Lucky for you I found (Fred's) photo of the socket method. It's a 10mm 1/4" drive socket. Works great for me.

https://www.fjrforum.com/forum//index.php/topic/116778-gen1-cam-chain-tensioner-cct-replacement-lessons-learned/?p=787762

SkooterG · Apr 18, 2019

Though I *think* to have slack on the chain to remove the cams I put the socket lower - like against the chain where it hits the crank sprocket.

Fred W · Apr 18, 2019

Ty-wrapping the chain to itself or jamming the socket behind the chain guide like I showed in my linked to post will only work for removing and replacing the CCT. You need to get enough chain slack to pull the cam(s) out for a valve adjustment.

For valve adjusts, with everything lined up at TDC, I just ty-wrap the chain to the top of each of the cam sprockets. That fixes their position in relation to each other so the only one you have to worry about changing is at the crank.

Most likely when you pull the cams up youll introduce slack on the front side of the chain where there should be none, and the chain will jump one tooth on the crank. The trick is, when putting everything back together, to turn the crankshaft backwards a few degrees (CCW) while fitting the chain at the crank sprocket, and gather most of the slack in the rear chain run. Tension the chain temporarily (use the socket trick) and turn the crank back CW to the timing mark. Everything should be back in time.

Its OK to turn the crankshaft backwards by itself, but you never want to turn it backwards very much when the chain is hooked up to the cams as youll put a lot of chain pressure on the CCT.

After everything looks good you reinstall the CCT, cut the ty-wraps on the cam sprockets and rotate the crank around a couple of turns by hand to recheck timing marks.

rbentnail · Apr 18, 2019

Don't use a socket and leave the tywraps for wire installation. Cutting corners will bring you nothing but heartache. Do the job and reset your timing with all 3 timing marks as described in your FSM. It's the only way to guarantee that you didn't screw it up. Ask the 2 guys in just the past 2 weeks who did tywrap and didn't check the timing marks. And the 30 or so guys before that that screwed it up with a socket or tywraps.

Fred W · Apr 18, 2019

Well, yeah, of course you have to check the timing marks. That goes without saying. Any time the chain is allowed or required to go slack you absolutely have to check and adjust the timing. The use of ty-wraps or a socket behind the chain guide is to make it so the timing is at least close to being correct. There is nothing nefarious about doing that. It isnt a shortcut, just good work practice.

I really dont see how you can screw up the timing when just changing a CCT if you keep tension on the chain the whole time. Its been when people (including paid mechanics in the shops) pull out a chain tensioner without restraining the chain that you get screwed up timing about 50% of the time.

dcarver · Apr 18, 2019

After everything looks good you reinstall the CCT, cut the ty-wraps on the cam sprockets and rotate the crank around a couple of turns by hand to recheck timing marks.

Fred, does this mean the CCT has to be removed to perform a valve clearance check?

And Thank You to all who have responded.

Intech · Apr 18, 2019

Don,

The CCT doesn't need to be removed to perform the check. It only needs to be backed out (take the tension off) if you have to remove the cams.

SkooterG · Apr 18, 2019

Well, I recently did a valve check and re-shim on my 09 FJR and used the socket to keep the chain from slipping and losing time on the crank sprocket while the cams were removed. And of course I used ty-wraps on both cam sprockets to keep those in time. And of course I verified timing before buttoning everything up. This isn't that hard to do. The shortcuts work. I've done it before without sockets and ty-wraps and it was a pain in the ass that added more time and frustration. Sure, everything turned out ok. But I would rather work smarter, than harder.

Auburn · Apr 18, 2019

dcarver said:
After everything looks good you reinstall the CCT, cut the ty-wraps on the cam sprockets and rotate the crank around a couple of turns by hand to recheck timing marks.

Click to expand...

Fred, does this mean the CCT has to be removed to perform a valve clearance check?

And Thank You to all who have responded.

Not for the valve check. If you have to adjust the valves, then you will need to pull the tensioner.

This all assumes you have #1 cylinder at TDC (#1 cams will point opposite of each other (intake faces the back of bike, Exhaust faces forward). There are two holes in the cams that will line up with the arrows on top of the cover for cylinder #3 and the timing marks on the ends of the cam gears will be even with the cases. The manual shows all the marks and rayZerman put up some great pictures (this is with engine out and the holes are not quite lined up with the arrows) it also shows the holes and the arrows to look for.

I ended up using a impact driver to remove the crank timing bolted to the end of the crank so it would break it free without moving the crank. (same for putting it back on - IIRC it is 45 ft-lb). It is keyed, so no worry about installing wrong. I marked the cam chain and the gear so I could visually verify that everything was lined up after I got the cams back in. I tie wrapped the camshafts to keep them in line also. The biggest issue is when putting the cams back in, is to make sure you get the slack out of the cam chain between the exhaust cam and the crankshaft gear.

After the issue I had trying to use tie wraps, it is easier to just remove the cams, not worry about the tie wrap and follow the manual re-install. I had to move the cam chain on the crank one tooth after I got the slack out of the chain between the exhaust and the crank.

Fred W · Apr 18, 2019

Damn, this SkooterG guy is pretty smart. It would be great to have someone like him around on this forum more often!

Best location to ty-wrap cam chain on crank?

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