South West Bikers | Motorcycle Forum

I have some spotlights bought for a bike with a tubular frame and crash bars but my current commuter bike has no accessible frame/bars for me to clamp them to. Ideally I would like to attach a 1cm square cross-section piece of aluminium to the flat part of the front of the frame/engine mount which is fairly easy to achieve (I have bodged it for now but will get some proper bolts if I can sort the rest out) and use the integral clamps to attach the lights. Unfortunately as they are designed for circular steel frame they don't fit well on the square strut (well they do but with no ability to adjust direction.

So I figure what I need is a thingy to convert a 1cm square strut to a 1.5 to 2cm circle which I can then clamp to. I've toyed with trying to fabricate something out of dense rubber but surely there is something out there which will do the job.

My problem? What is it called so I can search for it! Thanks in advance.

Not what I was picturing but it could well work if I pop a bolt into the threaded hole and use that to clamp to. Unfortunately I just searched fo them and they are to fit 1 inch strut which is overkill for the job. I'll have a search for smaller ones later.

Thanks

How about shaft collars?
They aren't' square inside but I'm sure they would grip well another to hold some small spot lights.

http://www.bearingboys.co.uk/Shaft-Collars-2548-c" onclick="window.open(this.href);return false;

Stick some photos up of what you have, where you want it to go and the location points. Someone may come up with an alternative solution.

I think Richard's suggestion will work but I suspect there may be a better way. Images on forums always flummox me so her is a link to a photo of the jury rigged proof of concept fitting:

https://www.dropbox.com/s/8ldi3w9qj6piv ... 6.jpg?dl=0

Just done a little more searching and found SQUARE BORE SHAFT COLLARS



ISO actuator shaft adapters


Max airtech adaptors
https://www.maxairtech.com/hardware/adapters/" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;


How about those - getting warmer?

Yes, definitely. The green ISO ones look almost perfect, sizes on both shaft adaptors look ideal. The only improvement would be more "teeth" on the exterior to allow finer adjustment. That may not be necessary as the light clamps have fine teeth. I'll try to get some of those if no one comes up with somethign even better.

Thanks again.

Look in the gallery section on here, there is a step by step way to do it.

Looking at that photo, why not use round bar and then just file a small flat on the area where it fits to the frame?
Then you can clamp it or drill/tap through.
Easy and quick fix.

I thought square would be easier to attach to frame. I'm not sure which way is better now but I'd rather have a light fall off than the whole assembly.

Why would a round bar fall off?

It would be against a flat surface so not much friction leading to it slipping down (I'm not willing to put a hole in anything which is part of the frame) and working loose. The bar I can back with some rubber and tighten more effectively. I can also use almost any bracket to hold it.

The round one would also need to be a bit thicker (the clamps range from about 15 to 25mm)

Having said that I am only guessing as I am a rubbish mechanic let alone engineer.