Gap between top of fork covers and bottom of top bridge? After tapered bearing install.

[BillinSC]

So I just installed a set of All Balls tapered bearings on my '73 CB 750. I'm certain all the races are seated and the correct washers are being used and in the correct position/order (per the instructions). The thing is that now when re-assembling the front forks (in particular the upper fork covers), there seems to be about an extra 1/8" gap between the top of the cover (with the upper isolator in place on the cover) and the under side of the top bridge (triple tree). I seem to recall when disassembling there was little to no gap and the covers were slightly wedged in place. It's almost as though the upper and lower triple tree are now a little further apart? I disassembled the triple tree to double check that the races are seated properly and the bearing on the steering stem is also seated properly (there does not seem to be any gaps that would account for the 1/8" gap I'm seeing up top).

I also tightened the spanner nut to the point where everything was pretty snug and a bit of turning resistance and then backed off about a half turn until turning was nice and smooth. So it seems as though all the parts are compressed properly.

The only thing I can think of that would make up this difference is the washer under the bearing and dust cover on the steering stem. I did the measurement of the old bearings and ended up using the thinner of the two washers provided in order to be within the +-1mm height measurement specified in the instructions. Also the steering stops seem to be right where they should be relative to the steering tube stop plate.

Is it normal to have a little gap where I'm seeing it? Just trying to check my work.

Thanks!
Bill

 

[grewth]

I think that you'll find that the new taper races are actually "taller" than the old cup and cones + ball bearings.
Pity you didn't measure them before fitting, hindsight would be a wonderful thing wouldn't it ?
I can only suggest that you find some way to shim out the gap and make the headlamp mounts are tight fit once again.
Maybe a couple of big stainless steel washers, narrowed to fit ?
I'm sure you'll manage to engineer something

 

[Loki]

Can you remove the washer under the bottom bearing without causing any fouling issues? Did you get the correct kit for your year and model? I fitted AllBalls taper bearings to my 77 F1 without any issues but I don't have shrouds between the top of the forks and I didn't have original bearings to measure and work from, just measured mine and between top and bottom yokes it is 181mm measured at the outer side of the forks, don't know if this will help as I don't know if the fork yokes are common to all years?

Loki

 

[grewth]

F1 yokes are different from anything on the K0 to K6 models.
Offset between the steering bearing axis and the fork tubes is different, although the fork tubes are the same diameter and distance apart, if that makes any sense ?
Would that be the "trail" that got altered ?
I can never remember that stuff.
I think that the F series also got a slightly different rake at the headstock, and maybe changed again for the F2 ?
Or maybe not.
The headlamp carrier frame on the F1 slides into two rubber bushes on the lower yoke, so you wouldn't notice a small increase in distance between the top and bottom yokes, the headlight frame will just sit a little higher in the bushes.
The F1 top yoke is (I think) unique to the F0/F1, but the lower yoke went on to serve on the K7,K8, and 750A paired up with the F2 top yoke.
Right.
I'll take my Anorak off now !

 

[Loki]

How about fitting an O ring of suitable dimensions on top of the fork covers to take up the extra clearance, once in there and snugged down I doubt if anyone would notice them?

Loki

 

[BillinSC]

Yeah, I've found through more researching of similar threads that this gap is a common issue with the tapered bearing upgrade due to the slightly different stack heights. Using the seal and the thinner of the two washers under the lower bearing gives you basically the same stock stack height as stock but the only way to get the same stack height at the top end is leave off the seal and the upper washer (from the kit). Those two components are raising the height of the top bridge (triple tree) by about 4mm. However, leaving the washer out only allows the raised ears/nibs on the under side of the spanner nut to contact the inner bearing cage unless you grind them off.

Since I decided I wanted to use the kit as designed (with the provided upper washer and seal) and live with the gap, I found/ordered some 35mm x 45mm x 5mm black o rings (Amazon) to bridge the gap. Havent received them yet but I expect they'll do the job.

 

[hinksy]

Put in the same kit in my F2 ( all balls ) I noticed the top race sat proud of the stem , which meant I had to use the smallest shim to even do up the yoke with enough threads . But it all worked and my brackets are held in as supposed