Fork friction dampers

[Bob Mather]

I have a 1932 Flyer with single downtube frame and Brampton Monarch forks and it handles really well _BUT. When I grease the fork spindles, grease appears at the tell tale holes at the outer ends, but a small amount gradually contaminates the four friction dampers over time until on fast bumpy bends, the front end starts to act like a pogo stick. Slacken off the dampers, add some degreaser and all is well for a fair while.
Reading through a stack of old ‘Yowls’ in an article by Titch Allen he stated that he found friction discs cut from thin plywood worked better than the original material and that he lightly greased them before fitting to stop scuffing. Anyone tried this and if so whats the verdict?

Regards
Bob Mather.

[Martin Heckscher]

Hi Bob,
I can’t comment on Titch’s plywood suggestion, but very recently when I fitted new spindles to a set of Monarch forks, I fitted some suitably sized O rings in an attempt to reduce the problem that you describe. It is too early to say whether or not they will make any difference.
Previously, with grease contaminated friction material, I found that I needed to use more leverage on the adjuster than I could apply with fingers alone in order to gain the required level of damping. I did worry slightly about whether I would break or damage the adjuster but it survived unscathed.
Best wishes
Martin

[BRIAN MARSHALL]

Hi Bob,
When I was stuck for some correct size friction discs several years ago, I made some from two layers of “FORMICA” kitchen unit laminate, Araldited together, shiny side to shiny side. I don’t know how resistant to grease it would be, but it is worth a try as it cost me nothing and certainly performed well and was durable, in both Bentley and Draper fork stabilisers and an Andre steering damper.

[Bob Mather]

Hi Martin and Brian,
Thanks for the information, will try the ‘O’ rings and Formica discs.

[efr215]

Another possibility is the Phenolic resin based material manufactured under the trade name “Tufnol” it is made in several grades and thickness, the thinner sheets are used for circuit boards, the type reinforced by layers of linen, it used to be called “carp brand” would probably be favourite. A similar sheet material made from GRP is also available but is more aggressive on cutting tools. The obvious sources for such materials would be the likes of Radio Spares or Maplin Electronics.

[Roger Moss]

It used to be possible to buy friction material in sheets from about 1/8″ thick. I suggest you consult your local clutch and brake relining company
Consider that the friction material used in a ring on modern clutch plate available from Iam Pearce and the SOC Spares Scheme
It must be available if we have it on our clutch plates.
In addition, the modern material is far better at coping with oil.
While we are at it, perhaps a tip is in order
If your clutch is gummed up with oil and will not free properly
Put bike on stand so you can revolve rear wheel
Put into bottom gear
Take shoelace or string, hold clutch lever in and bind with string to retain it
Try turning the rear wheel and note drag
Put catch tray under gearbox
Mix up about 1/2 pint of petrol with about 15% oil in a flexible spout pourer
Get someone to revolve the rear wheel
Pour the mix over the clutch while revolving the wheel
You will feel the difference almost immediatly
A bit messy, but you can always wipe it’s bottom
It works for me and keeps my clutch in top effective condition even with about 42bhp going through it.

[Anonymous]

I can supply the friction discs as used in steering dampers on bikes such as BSA and Ariel bikes – I’m not sure what they are made of as I’ve never bought any myself but they are listed in my trade catalogues. They could fit or be modified to suit fork dampers I’d guess.

Let me know if you’d be interested and I could get a price/availaility.

Best regards,
Richard

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