1968 B44 Victor Special Fork Damper Bolts.

[Andy Kay]

The forks on my Victor Special are the pinch bolt type and are fitted with damper tubes which are held in place with an Allan head bolt.
One leg has been leaking via the damper bolt so I removed it to see what the problem was.
The parts manual shows an aluminium washer under the bolt head which was missing. I ordered a couple of replacements, but they didn't fit.
The outer diameter was too large so they wouldn't fit in the recess in the bottom of the fork tube.
I found some nylon washers that would fit so I thought I would give them a try. When fitted I began to refit the front wheel but I couldn't get the wheel spindle past the damper bolt.
On closer inspection I could feel the head of the bolt very slightly proud of the recess in the bottom of the fork tube.
It turns out that there is insufficient depth in the recess to allow the fitting of any kind of washer no matter how thin.
As a stop gap measure I have applied a couple of wraps of PTFE tape under the head of the bolt and it appears to have worked so far.
I can only think of attempting to reduce the depth of the bolt head slightly to allow a soft washer to be fitted as a permanent fix.
Liquid thread sealant is no use as the fork tubes aren't threaded, the bolts screw into the ends of the damper tubes inside the fork tubes.
Has anyone else had a similar problem and how did you fix it?

[Mike40M]

Just guessing, never needed to take apart forks on my Victors. But done fork jobs on other bikes. As the aluminium washer should be 1/32 thick, it might be possible to grind off a little on top of the cap screw in order to clear the spindle. Are you 100% sure the damper unit is rotated to the right position? See Rupert Ratio volume 2 page 70.
Curiously, on my B40WD which has same fork as you, parts list states the washer as steel, cadmium plated 21/64 id x 7/16 od x 1/32 thk.

[neil1964]

Cap head screws are not original so likely they are too deep - hence your clearance issue.
I guess PTFE will work
Ideally correct original part number bolts and washers (assuming the damper has not been drilled and different thread cut) would be ideal solution.

[Andy Kay]

The cap heads are 5/16 x 3/4 bsf and the recess in the fork tube is a just fit.
I have seen an older post where someone thought the bolts should have a groove with a ptfe insert down the side to create a seal.
I can't see this working as there aren't any threads in the fork tube to create a seal. The threads are in the damper tube which is sat in the oil inside the fork tube.
I have got a couple of spare bolts, I'm going to have a go at skimming 1/2 a mm off the top of the cap head and another 1/2 mm from the underside. That should allow plenty of clearance for a soft washer.
Thanks for the replies.

[Rupert]

Agreed, the original ali crush washers are 1/32" thick (about 3/4 of a mm) and that reduces when the allen bolt is tightened and they crush down even thinner, which means the head of the allen bolt does not protrude and foul the spindle. The OD of the crush washer is the same as the OD of the allen bolt head.
I've also found some original Allen bolts with a thin nylon insert along the length of the thread. Somebody at BSA must have thought it a step in the right direction. Same feature sometimes found on late chaincase drain screws, where it works.

[Andy Kay]

Hi Rupert,
Where did you get the crush washers from?
The ones I ordered were far too large on the outer diameter and wouldn't even fit in the recess in the end of the fork tube, even though they were supposed to be the correct part number.
Regards
Andy

[Rupert]

Hi Andy, sorry for delay, only just looked back on this post.
I got them from Hansen the Danish BSA importer about 25 years ago but that supply no longer exists...
I have a couple left, if you're desperate please PM me for details.

[Andy Kay]

Hi Rupert,
Thanks for replying.
I have ordered some from an engineering company called CPC, they are based in Bodmin I think.
Anyway they claim that their crush washers fit properly and do the job, so I'll find out when they arrive.
Kind regards
Andy.