Bum Pad

[simon.holyfield]

Folks, my civilianized W/NG appears to have had a bum pad type pillion seat from the 1953 picture I have of it.

Can anyone help me understand what type of foam I should use to make one? Should I use a thick layer of hard foam and a thin layer of softer foam?

[Richard Woolnough]

Hi Simon, is the seat ever likely to carry a passenger?, if not will it really matter what the supppleness of the foam should be?
but to answer your question, the chap who reconditions seats locally will use a rather firm foam for the lower 2/3rds and a softer for the upper 1/3rd. kind regards

[iansoady]

I reshaped the seat on my modern(ish) Honda to suit my ageing knees and used what they call rebond for the main structure. This is made up of chips of foam glued together and is very firm.

Oddly enough, it's more expensive than conventional foam.

[Brian.Fosh]

Hi simes,

Here are some photos of a period pillion pad that has fallen apart over the decades...
It has a Dunlopillo style pad but Might help you with options on shape.
I guess to replicate its spring-like characteristics and keep a good shape, you might consider a harder foam on top, softer beneath?

Rgds brian.

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[leon.mitchell]

In the early 1930s, bum pads for racing were filled with air! At the 1932 TT races all of the placed bikes used these "air cushions" made by either Moseley and Lycett. I've never seen one, but I assume they had a bladder like a football. If anyone has an original - even if only suitable for a pattern - I'm looking for one for may non-Ariel racer.
Cheers
Leon

[adrie.degraaff]

I had one of Lycett, it was leaking so i put a innertube in, think it had a zipper at the rear.

[adrie.degraaff]

Can anyone help me understand what type of foam I should use to make one?

I have the original foam and plate parts laying about, you can have them for free, if some one can pick them up at the Dutch rally.

[ColinPeck]

Hi Simon, I've found the best foam to use is from a scrap Japanese bike seat, this is cold molded foam and very springy even when it's old.
Colin

[leon.mitchell]

I had one of Lycett, it was leaking so i put a innertube in, think it had a zipper at the rear.

Thanks Adrie - now that you mention the zipper I think I have seen one. I thought the zipper was for poking tools in under the foam! Is this one - on Grahan Walker's 1928 Ulster-winning Rudge - like the one you had?

Simon - here's an advert for a Moseley pneumatic bum pad probably from the period of your bike. Now that would be a talking point.

Cheers

Leon

Lycett air cushion bum pad?

Moseley pneumatic bum pad

[Steven.Carter]

That's a great idea.