Z1OwnersClub GB

I'm currently rebuilding the front end, with a new spoked wheel, which included fitting new bearings and the spacer between the bearings, and also returning the forks to being the "right way around", with the calipers in front of the forks.

When everything is tightened up and correctly torqued, there is a small difference in the gap between the left and right disc, and the corresponding fork leg, with the left hand fork leg to disc gap being smaller than the right hand gap by just under 1 mm (when measured with a stack of feeler gauges). The brake calipers/pads have been refitted, and the wheel spins freely with no problems or run out.

I'm about to take everything apart again to check dimensions, but does anybody have a view on a) whether this is a problem, and b) if so, any ideas on where the problem may lie?

First of all, just checking some basics,
I assume both the fork legs/stanchions are straight ?

Secondly, with the front end assembled is the front wheel rim in the middle of the fork legs ? If you know the actual wheel is correctly centered then you are halfway there !
The best way to measure this is with the tyre removed from the rim, but if it's not or you don't really want to remove the tyre it should be fairley easy to check this with the tyre fitted.

If the fork legs have been reversed does that mean they have swopped sides ?
If so the speedo drive will have had to have stayed on the left leg so you might need to check you have the correct spacers fitted on the correct side, (assuming the Z1000A1 is the same setup as my Z900A4).

1mm difference on one side actually means a 0.5mm difference left to right.
These bikes weren't that accurate and that 0.5mm could be down to anything from the thickness of the plating on a wheel spacer to the depth of material on the fork leg.
Not really a problem except for those with OCD..

Thanks CAT3.

The forks appear straight, and are not twisted in the yokes. The wheel spins freely, and there is no play in the bearings or the forks. I've checked with an inclinometer app on my phone, and the angles on both legs match. My concern is that when checking rim run out and brake disc run out, the wheel does appear to be slightly off centre. The gaps between the discs and the fork stancions are not the same on both sides. The difference is only 1mm when measured, but it is there.

The legs have not changed sides, but the stanchions have been rotated so that the brake caliper lugs are now at the front of the stanchion. Tha calipers have been fitted with the pads in and there is no binding or sticking on wheel rotation. The speedo drive is on the left, and is working OK, as I can see the drive cable moving as the wheel rotates.

I have fitted a new front axle and right side spacer, so I will go back and check the dimensions on those, as I did not do that before fitting them.

CAT3 wrote:First of all, just checking some basics,
I assume both the fork legs/stanchions are straight ?

Secondly, with the front end assembled is the front wheel rim in the middle of the fork legs ? If you know the actual wheel is correctly centered then you are halfway there !
The best way to measure this is with the tyre removed from the rim, but if it's not or you don't really want to remove the tyre it should be fairley easy to check this with the tyre fitted.

If the fork legs have been reversed does that mean they have swopped sides ?
If so the speedo drive will have had to have stayed on the left leg so you might need to check you have the correct spacers fitted on the correct side, (assuming the Z1000A1 is the same setup as my Z900A4).

Thanks Zed1015.

Great to get some feedback from somebody more knowledgeable, that's the real benefit of the forum. I'll try to get my OCD to calm down then, and focus instead on getting it finished and on the road

zed1015 wrote:1mm difference on one side actually means a 0.5mm difference left to right.
These bikes weren't that accurate and that 0.5mm could be down to anything from the thickness of the plating on a wheel spacer to the depth of material on the fork leg.
Not really a problem except for those with OCD..

zed1015 wrote:1mm difference on one side actually means a 0.5mm difference left to right.
These bikes weren't that accurate and that 0.5mm could be down to anything from the thickness of the plating on a wheel spacer to the depth of material on the fork leg.
Not really a problem except for those with OCD..

Good points that man !!

All sorted now, thanks for the feedback. I ended up turning 1mm off the spacer on my lathe.