Topic: CB750 K7 front wheel spacing

[drpoyser]

Hey there, I've just recently restored a K7 CB750, but when out on the road, under braking the bike pulls hard to the right.

I'm not quite sure what the issue is but I've noticed that the front wheel sits offset in between the from forks.
Looking from the front the disc side is around 5/6 millimetres closer to the fork than the other side.

Is this normal?


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[Stoli]

Both of my K8s are like that. Neither pulls to the right though. I'd be curious as to what is causing that. What about the back wheel? Is it aligned with the front? Steering bearings? Swing arm bushings?

How about the forks? The suspension in particular.  If they compress at different rates or one is binding a little, that might cause a pull to the side during braking. Fender brace on tight? I would think that the other issues I mentioned would be noticeable at other times as well and not just when you are braking.

[drpoyser]

Hey Stoli, that's good to know. I had the front end off today and checked the forks which seem to compress the same but the steering bearings were awful. I think I've fixed it by installing a washer as a spacer at the bottom. First run went horrendously, with wobbles all over. Then everything just seemed to pop into place on the second tighten and no more pulls under braking (so far at least). I'll let it sit over night and have another few runs in the morning. Thanks Bud.

[martin99]

I've never owned a bike where the front wheel is offset from centre in the forks. Then again never owned a K7/8 either. But that doesn't sound right to me.

[MCRider]

I've never owned a bike where the front wheel is offset from centre in the forks. Then again never owned a K7/8 either. But that doesn't sound right to me.

There have been many threads, mostly schooled by Mark Paris aka HondaMan, where it was discovered the K0 front wheel was offset.

That doesn't help or even relate to your problems, perhaps, but  it does point out that wheels are not always centered.

[scottly]

The rim/tire should be centered between the forks. The most common cause for a centering problem is improper axle installation, with the nut on the right side instead of the left side. Spacers shouldn't be required!! Please post pictures of your current set up.

[MCRider]

The rim/tire should be centered between the forks. The most common cause for a centering problem is improper axle installation, with the nut on the right side instead of the left side. Spacers shouldn't be required!! Please post pictures of your current set up.

Agreed. Whatever the problem is, it shouldn't require odd pieces of non-OEM hardware to make it work.

[Stoli]

Nuts on the left on both K8s. I had read Mark's info regarding the offset and was about to correct it with the spokes but noticed that the front was perfectly aligned with the rear and the sprockets were in perfect alignment as well so I figured that was more important and didn't change it. I dunno. Doesn't seem to be a problem.

[scottly]

Nuts on the left on both K8s.

Hex on the nuts located on the inside of the fork leg?

[drpoyser]

Thanks for your help so far on this. After measuring, the rim on the disc side is pretty much 1/4 inch closer to the forks than the other.

[Stoli]

Nuts on the left on both K8s.

Hex on the nuts located on the inside of the fork leg?

Yes. I don't think it would fit the other way, would it? I'm on the road for the next week or so, so I can't post any pics other than what is already in my build threads.

[drpoyser]

I'm pretty sure it can only go that way. I did try flipping it but it wasn't right. Now the bearings are sorted I'm no longer having any trouble and the turn in is fine in both directions. It's also totally stable. Interestingly I saw a 550K in a bike shop earlier and that also had a bias to the disc side for the wheel. So maybe that is correct?

[Stoli]

I don't think it as big as a deal as scott and mcr make it out to be. Certainly not a few millimeters. As long as your front and back wheels are in the same plane, I think that is the important thing. If you look at the rear end of the 77-78K there is nothing symmetrical or centered about it. The shock mounts are biased and if I remember correctly, the wheel isn't perfectly centered in the swingarm either.

If you have any more issues with the steering, AllBalz sells a tapered steering bearing set that is really nice and not a lot of money. Some guys have reported that the removal of the old races has been difficult but I just did it on a '76k that I am working on and it wasn't too bad. Bearings like to come out and go in perfectly square to the recess. Once they get cocked off a bit, that's when problems arise. Keep that in mind, and with a little patience any bearing can be replaced without a fancy hydraulic press. There are several threads on this forum that address the AllBalz installation. I've learned that a Mapp torch and a freezer are two of the best tools when fixing up one of these bikes.

Cheers

[drpoyser]

Cheers Stoli, I'll see how I get on for now then.