fork spacing and fibreglass mudguards

Working last night on the Norton forks, and I found 2 problems.
With the wheel in the forks and the axle pushed as far as it will go, there is still a gap of around 1.5mm before the axle nut is tightened. It’s a 74 disk wheel, and I have both the LH and RH spacers in place. The logical thing to do is to use a 1.5mm spacer to prevent the forks from being misaligned, but why this gap?

After I put a spacer in and tightened everything up, I found that the new fibreglass PR type mudguard dances around when compressing the forks. At first I thought it was the whole wheel that was moving, but it’s actually the mudguard. I presume this is because the fibreglass is so flexible, but it does indicate that the 2 sides are not moving in perfect symmetry. Presumable by fitting either the standard steel mudguard or some form of fork brace this can be removed, but can this be connected to the mysterious gap mentioned above? What do other people running PR type mudguards do?

Oh, and I also found a slight bend in the axle, so will be ordering a new one today. Sigh, if I’m to actually get this bike on the track at Spa in July, time is running little short…..

ok, now I've found gap-front-axle-t14621.html which says that the gap is normal. So that still leaves the question about why the mudguard is dancing and how to fix that.....

/Steve in Denmark, working his way through the mysterious ways of the Norton...

I would pull the wheel off, make sure the fork tubes and triples are not bent in the least and then take a measurement at the bottom where the axle passes through. This number should not change with assembly and if it does, something else is out-of-kilter. If the fiberglass mudgurad doesn't fit ( take a measurement between the legs where it mounts compared to a measurement of the mudguard itself) I would shim it with some plumbers rubber or a piece of an old inner tube until it fits. That way, neither the axle nor the mudguard is exerting any misalignment force on the fork.

The old steel guard/bridge and stays added to the strength , Norton forks will twist easy with no support.. hold the wheel between your knee's and twist the bars....then say Ho My God!

john robert bould said:

The old steel guard/bridge and stays added to the strength , Norton forks will twist easy with no support.. hold the wheel between your knee's and twist the bars....then say Ho My God!

Click to expand...

I read that Gordon Jennings discovered this during a magazine test (Cycle?) of an early Commando by flopping it back and forth through some tight switchbacks. He said it handled great on sweepers, but as soon as you manhandled it, it was a deathtrap.

I have fitted an alloy fork brace off a motocross bike.

any photos of the brace Danno? Which bike did it come off? what changes did you have to do?

Still wondering about what the PR owners see when bouncing their forks.

You can see it in this photo. Not sure what bike exactly, I think it was an aftermarket part for some old Yamaha motocrosser. Had to do some bending, tweaking and drilling to get it suitable.

Draw back to this type is the ripple it puts in the guard,it hard to form the shape into the guard, a gap under the bracket and guard distorts the job.

john robert bould said:

Draw back to this type is the ripple it puts in the guard,it hard to form the shape into the guard, a gap under the bracket and guard distorts the job.

Click to expand...

Yeah, I thought about putting it over the top, but it would have looked too clunky. And until I went with a smaller section front tire, anything stuck to the tire (mud etc.) would make a scraping noise on the bracket.