[RJ2112]

It actually does, in a way…. There’s a reason why the links get counted after you rotate the engine to TDC. You want tension on the driven side of the chain to ensure you account for the the slack.

The sprockets have fixed geometry, but the slack in the chain will make the length of chain change based on whether the engine is working against a load, coasting, or engine braking.

 

[BumbleBee1]

Here is a pic of what I have going on. This is assembled with tensioner installed. You can see in the pic that my pin count starts on a full link and not a half link like the manual shows. This is why I'm confused. Could i have jumped a tooth on the crank?

 

[PhotoAl]

Seems like that would make sense but where is the crank - TDC for this I'm presuming. Have you verified TDC with something like a dial indicator or the mark on the crank? Since you know what you are doing I'm sure you have addressed that but still puzzling. I presume the cam sprocket bolt holes are not slotted - would not think they would be. When I did my CBR600RR is was confusing as to how to read the marks and took a while to figure it out - I expected very exact precision but now know why folks degree cams as the factory tolerances are not as precise as I'd imagined. Not bad but less precise than I expected.

 

[BumbleBee1]

I checked TDC, and it jives with the 1,4 mark (I had the same thought). The motor timed as in the pic turns freely and seems to be in time, but the "half off" chain link issue has me second guessing my work. I always like things to match the manual. My only guess at this point is the cam chain jumped one tooth on the crank sprocket. The issue with that theory is that there is a bottom (cast) chain guide that should prevent that from happening. Still scratching my head...

 

[RJ2112]

There will be some amount of ‘stretch’ pin to plate over who knows how many operating hours your project has. I haven’t looked for a chain wear pin to pin distance, like there is for the final drive chain; the sealed environment and fixed distances should reduce the wear orders of magnitude but it will wear in the same manner. The plastic coating on the chain guides also wears away with hours even when the auto cct remains in place.

 

[owerr1]

Hi there, I've had a very similar experience with timing my gsxr 1000 k6 with 29k miles on it.
It was a stretched timing chain in the end that would stop it timing up as per the manual.
The stretch was tiny but noticeable against a new chain.
Fingers crossed you get to the bottom of issue.

Sent from my CLT-L09 using Tapatalk

 

[BumbleBee1]

I don't believe it is chain stretch, but it will check it out.

 

[owerr1]

The bikes are different, my experience with my gsxr, it would time up exactly like your photo, and no matter what I did to it, it always end up exactly like your photo.

I even spoke to a experienced suzuki tech who said it was fine how it was timed up, but I didn't agree and didn't like that it wasn't as per manual. Anyway mine was down to a stretched timing chain.

Hope you get it all sorted out

Please keep us updated with what you find

Sent from my CLT-L09 using Tapatalk

 

[Scumbag]

Did you have another topic about this timing thing before? Seems like I remember seeing this and even checking a motor I had on the bench at the time and replied. Idk maybe I’m just getting old lol


But I have seen this several times before. I tiny tiny amount of chain stretch will throw that pin half pin start measurement off. You seem to know what you’re doing. Double check everything and if everything seems right except the pin start count then go with it. You’re good.

 

[BumbleBee1]

Did you have another topic about this timing thing before? Seems like I remember seeing this and even checking a motor I had on the bench at the time and replied. Idk maybe I’m just getting old lol


But I have seen this several times before. I tiny tiny amount of chain stretch will throw that pin half pin start measurement off. You seem to know what you’re doing. Double check everything and if everything seems right except the pin start count then go with it. You’re good.

Yea, guess thats where I am in this process. My head hurts. I haven't talked about this in a different thread, but, I did time this same motor a few weeks ago and the links lined up right. I had to take the top apart again because of an issue I had with the head gasket. That's the part that really bothers me. I understand the stretch theory, but I'm not convinced that is the issue. I really appreciate everyone's input on this (I need all the help I can get right now). the chain jumping one tooth on the crank is STUCK in my head but I just don't see how that would have happened, but would explain the pin count issue.

 

[RJ2112]

Did the head gasket thickness change?

 

[BumbleBee1]

No, same thickness. Do you think a couple .001's would cause this? just curious.

 

[RJ2112]

Probably more bolt torque/pattern, but it’s a really small consideration. We’re working on an identification by exclusion at this point. What remains, however improbable must be the truth….

 

[Brader]

The issue with that theory is that there is a bottom (cast) chain guide that should prevent that from happening. Still scratching my head...

If it helps you, I'll tell you that many people remove that cast metal tab to replace the chain without having to unhook a link. Do you know for sure that your engine still has that tab?

 

[BumbleBee1]

If it helps you, I'll tell you that many people remove that cast metal tab to replace the chain without having to unhook a link. Do you know for sure that your engine still has that tab?

Yea, its there, i have looking at it for days. It is haunting me... I would feel better if it wasn't there. At least I could explain what happened then.

 

[RJ2112]

Have you inspected the sprockets for broken teeth? Stiff links in chain?

 

[Scumbag]

Well hopefully it’s fine and you are just being over cautious. A tiny bit of stretch over the length on the chain does come out surprisingly long. Good luck brother.

 

[BumbleBee1]

Well, I have checked everything that I know how to check. Everything looks and measures right. I have determined that it is NOT possible to jump a link on the crank without damage, and I believe that these 6R motors will not rotate with the sprockets off even 1 tooth. So, with all that, I will time it back up the way it is picture above and hope for the best. I have made an appointment with a mental professional to try and sort all this out in y head... They will probably tell me that I'm one link off...

 

[Scumbag]

Lol “one link off” 🤣😂. That was perfect comedy there buddy. I think. Well I’m 99% sure you got this right. 🤞 if it grenades remember I just said 99% 🤣

Hopefully you are right tho. Surly you are right

 

[BumbleBee1]

I hope your right that I'm right... I think I said that right. Alright, I'm going right out to put it back together the right way. I hope,,, I'm right... Geez.