650ss Manx style seats

You might consider a late Atlas seat that has a hump.

Hi Tom,

I bought a Manx style seat from Burton's Bike Bits in the UK (with an alloy Manx style 5 gal tank and central oil tank). My bike is a Sept 62 650 SS (slimline). I think the seat was somewhere in the vicinity of 115 pounds

The seat itself is just fabric and foam over a plastic base so I made up a base for it out of 4mm aluminium sheet using some cardboard to template the plastic seat base. I then fixed the seat to the aluminium base with the bolts/fixing that came with the seat

I then made up some brackets out of 2 mm aluminium and steel to mount the seat with bolts to the frame. I mounted the seat over the rear cross bolt and brackets on the subframe, whereas some people on various bike forums, advocate cutting the brackets completely off.

It's a personal choice, but I don't like the look of seats mounted flat on the rear subframe on slimline frames. They appear to droop down towards the back, as opposed to seats mounted on wideline frames (like a Manx) which have a good angle to them.

Again its personal thing, but I also didn't want to change my frame in anyway by cutting off brackets, so that any future owner could refit it's original road going trim (which I have stored safely away) should they feel the need.

The aluminium base gives you secure fixing point to the frame and also allows you to undermount a Lucas 564 tail light so that you can run a short Manx style rear guard. The undermounted tail light is actually a lot brighter than normal as its not mounted in direct sun light. I'll try to upload some pics so you can follow what I'm talking about. Little bit of a fiddle but worth the effort I think. Cheers

Thanks Tom,

Photos are few months old now and my bike is about to be fitted with a rear conical hub, a Manx style fork damper and a few other bits and pieces.

The rear sets (purchased from Norvil) were fitted into the frame gussets where all the Norton publications say to fit them (I think it was an inch down from the swing arm pivot bolt and slightly forward but I can't remember now) It was quite easy to drill and fit them.

The seat base mods are pretty easy and it can all be done with a jigsaw and an electric drill. I played around with the angle of the seat until I found something that looked right. The aluminium base sits right on top of the cross bolt brackets. Its a lot more secure than my original seat and surprisingly comfortable.

Give aluminium a go, its easy work with as you can cut it and shape it with hand tools. I made up my brackets to secure my tank strap toggle to the through bolts on my oil tank out of aluminium, to avoid welding a bar across my frame like the widelines have. Cheers