Topic: Help! Rear wheel is drifting left - With Pictures!

[GammaFlat]

Here's 2 different carriers.  It's hard to tell in the pic, but I thought that it not only affected chain alignment but also affected where your spacers went on your axle.  hmmm

[crazypj]

Is the sprocket carrier beaing in good condition? (looks a bit nasty in pics)
In of the earlier pictures it looked a little crooked.
 Is spacer #15 in place in middle of wheel?
 
 

[GammaFlat]

...it looks like a 77-78 rear wheel assembly which is wider than the one from a K4. Is it a 17" or 18" rear tire?

...I compared a 77 rear sprocket carrier with an earlier one and it is wider (sticks out farther) The early and late sprockets interchange so a late hub (wider) could have been used with the early chain size if someone swapped the sprocket.

I just read through the thread again and I think Don was pointing at the right issue early on.  
This looks like parts from different years??

[GammaFlat]

I guess we should figure out a way to measure the carrier.  If it's a K4 type, I don't know what the crap is wrong.  If it's a K7/K8, he can put an earlier one on possibly to bring the chain inward.  This may cause other issues though with the engine sprocket being more outboard - argh!

[MCRider]

Wow. Sounds like you've got a hypothesis. Have to wait for the playout.

[GammaFlat]

MC, what's your experience with chain alignment?  I'm trying to recall conversations I had with HondaMan about how much mis-alignment you could get away with... I'd like to blame age, but my memory is about the same as it was 30 years ago - not to good   It seems (IIRC) that perfect chain alignment is not necessarily required. As a matter of fact, the cam chain in our engines is intentionally off a little to prevent harmonics or some other similar reason...

[GammaFlat]

The CycleX site: Scroll about 3/4 down.

..has an explanation about the carriers.   Apparently, there's a 10mm difference between the two carriers. 

From Cyclexchange.net:

This photo will help you identify if you have a 69-76 or 77-78 carrier.
Left carrier ( early) has a 26mm height. Right carrier ( late) has a 36mm height.

[Gamma]

Looks like a later engine for a 630 chain and sprockets.  Front sprocket held by single bolt.  The front sprocket is I believe 10mm further to the left on this engine, this means the swinging arm and sprocket carrier and spacers must suit, to ensure correct chain alignment etc:  BadMans looks to have a thinner sprocket carrier fitted at the wheel hub for a 530 chain.  I also think the swinging arm maybe wrong, but I'm not sure, but I have just fitted a K7 swinging arm onto a 1976 F1 frame and engine, and the K7 swinging arm is not symetrical, it is 10mm wider from the centre of the hub to the left of the bike, this I believe allows for the bigger sprocket carrier.
The 2 carriers in the picture gammaF have I believe the same external spacer, but the inner one on the K7 (right hand in your picture) is longer.

[MCRider]

MC, what's your experience with chain alignment?  I'm trying to recall conversations I had with HondaMan about how much mis-alignment you could get away with... I'd like to blame age, but my memory is about the same as it was 30 years ago - not to good   It seems (IIRC) that perfect chain alignment is not necessarily required. As a matter of fact, the cam chain in our engines is intentionally off a little to prevent harmonics or some other similar reason...

No real experience of any technical value. My hands on expereince drops off around 1974 and all I "know" after that I've picked up, and find inaccuracies aplenty.

I do know the early CB750 front sprocket attachment allows the sprocket to float on the shaft a tiny bit. A bit disconcerting if one didn't know that's the way its supposed to be. I always figured it was so the sprocket could "self align". Seems the 530 chain doesn't fit tight side to side on the sprocket, so that much is allowed anyway, 1/16" or so.

I'd say that's true on the cam chain as well. That is, if you had one in front of you, you could slide the cam chain side to side on the top sprocket a bit. Must happen while its running.

I don't recall my 88 HawkGT having any slop in any angle of the sprockets and chain. They may have goten better over the years.

[Bad Man]

You folks are absolutely amazing!

I took the rear tire into the shop (NOT the one I bought the bike from) and had the tire put on. While there I had the mechanic take a look at the bearings and jazz... he said they all looked good to go. (he had prefaced this with 'bearings are either good or bad')

I suppose that I need the locking washers and bolt for a '78 then.

Nothing like diving head first into a whole new learning process to get the blood flowing.

[CycleRanger]

You folks are absolutely amazing!

I suppose that I need the locking washers and bolt for a '78 then.

Nothing like diving head first into a whole new learning process to get the blood flowing.

Actually, it sounds like since your engine is a '78 that you need a swingarm and a sprocket carrier from a '78 as well....

[MCRider]

You folks are absolutely amazing!

I suppose that I need the locking washers and bolt for a '78 then.

Nothing like diving head first into a whole new learning process to get the blood flowing.

Actually, it sounds like since your engine is a '78 that you need a swingarm and a sprocket carrier from a '78 as well....

I'm really cold on late model parts, but that's what its sounding like. The salvage yard didn't realize, as i wouldn't, that there was that much difference in the 78 parts.

[Bad Man]

Yea. I was afraid of something like that.

[bollingball]

We have a franken bike. My (750K8) front sprocket has one hole one large bolt one large washer it (does float on the shaft allmost a 1/4 in. self aligning. on the rear end I have the tall carrier my shocks have the offset on the bottom.630 chain the swingarm bushings have the lip (tophat) yours are not in the pic.you may have the wrong swingarm.The chain guard does not look correct

[GammaFlat]

I'll measure later but eyeballing it, I'd say the K7 swing arm is 3/8ths" longer and 5/8ths" wider

[Gamma]

K7 swinging arm and hub and carrier.  Only difference is I've machined 10mm off the carrier face to fit a 530 sprocket.

http://i192.photobucket.com/albums/z293/galaxy8155/DSCF0070.jpg[/img]]

http://i192.photobucket.com/albums/z293/galaxy8155/DSCF0069.jpg[/img]]

[bollingball]

How about you frame # if it is a K8 maybe a donor K8 would get you all the part and then some.

[Bad Man]

How about you frame # if it is a K8 maybe a donor K8 would get you all the part and then some.

Frame number is as follows: CB750-2510204