Author Topic: improving brakes?????  (Read 816 times)

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Offline andertheke

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improving brakes?????
« on: 29 Dec 2018 at 15:46 »
Dear Experts,

has anybody a good idea how I could improve my rear brake that it works as it should?
Now there is only a marginal slowdown.

Thanks for your answers.
Peter

Offline graeme

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Re: improving brakes?????
« Reply #1 on: 02 Jan 2019 at 20:06 »
Welcome to veteran motorcycling Peter!

Yes the brakes are not very good for anything more than marginally slowing down the machine, you have to ride them accordingly and not be dependent on the (non)brake. That said, some riders have found that fitting a softer material, of the type that is used for the wheels on "wheelie bins" (household garbage bins that are emptied kerbside) can make the brake quite effective - though at the expense of longevity, the softer material wears away quite quickly. Many have also used wood for the brake block with good effect, and there are threads on this forum about this. In Australia the best wood seems to be a hardwood type as from eucalyptus trees. I can't remember what the preferred type is in Europe, I'm sure someone will chime in with the species. Best of luck!

Cheers, Graeme

Offline Eric S

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Re: improving brakes?????
« Reply #2 on: 02 Jan 2019 at 20:46 »
My uncle told me his Motosacoche Manual advise to carry some sand on the bike to improve braking on wet conditions !

Offline andertheke

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Re: improving brakes?????
« Reply #3 on: 05 Jan 2019 at 16:52 »
Graeme,

thank you very much for your answer. I'm astonished that wood possibly seems to be better than rubber.
Usually Wood becomes hard by heating it (as the stone age people did) due to friction,
so I better will try your "wheelie bins" idea  :lol:


Best regards
Peter



Offline eddie

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Re: improving brakes?????
« Reply #4 on: 05 Jan 2019 at 17:02 »
Peter,
           You may find that a rubber based material is too effective - that was the case with the VMCC's 'retarding material'. When used on veteran Douglases, the rear wheel often instantly locked up. Wood seems to be a good alternative to a 'Ferodo' type material.

  Regards,
                 Eddie.

Offline douglas1947

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Re: improving brakes?????
« Reply #5 on: 06 Jan 2019 at 16:28 »
Hi Peter,

I have also restored horse carriages in the past and these had originally wooden blocks braking direct on the steel tyre of the rearwheels.
Best results have blocks out of soft wood. I used best blocks of Poplar  (german: Pappel).
Harder wood has less friction and tendency to sream.

If you like I will have a look at my workshop for some wood.

Michael

Offline andertheke

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Re: improving brakes?????
« Reply #6 on: 06 Jan 2019 at 19:14 »
Hi Michael,

thank you very much, I will first do some experiments with rubber.

Best regards
Peter

Offline Bob M

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Re: improving brakes?????
« Reply #7 on: 06 Jan 2019 at 22:27 »
The friction qualities of various types wood has been well documented by engineers and published in Machinery's Handbook many years ago. To quote my 1919 edition, page 521 on,

"For brakes where wooden brake blocks are used on iron drums, poplar has proved the best brake-block material. The best material for the brake drum is wrought iron. poplar gives a high coefficient of friction, and is little affected by oil. The average coefficient of friction for poplar brake blocks and wrought iron drums is 0.6; for poplar on cast iron, 0.35; for oak on wrought iron, 0.5; for beech on wrought iron, 0.5; for elm on wrought iron, 0.6 and for elm on cast iron, 0.35. The objection to elm is that the friction decreases rapidly if the friction surfaces are oily. The coefficient of friction for elm and wrought iron, if oily, is less than 0.4."

All Northern Hemisphere woods unfortunately, native Australian hardwoods don't get a guernsey but there is enough info there for you to get the grey matter bubbling over.

As an aside I find having an early edition of Machinery's Handbook helpful in understanding how the factories of the day went about their business, what materials and info was available to them and how they used them. It can be surprisingly useful.
Cheers, Bob