Motorcycle side stand from composites?

General Composites Discussions Composites Talk
#1

Hi All,

I have just started a new bike project (KTM 380 EXC supermoto build) and have been thinking about making some simple carbon fibre parts, mainly just the bodywork.

But I got to thinking about other parts that I need, then I wondered if it would be possible to use composites for the side stand? I am interested in giving it a shot, but I wanted to get some input from those more experienced than myself, because this is a load bearing part, a bit different to body panels that just sit there and look pretty!

The bike weighs around 110kg with fuel, so this is the weight that will be leaning on the stand. The stock stand is known to bend very easily, but I think that is dut to the mounting bolts. I think it’s possible to make the part from composites without the part being too bulky, because it only needs to support the leaning weight of the bike, not the full 110kg.

Here’s a picture of a standard alloy stand to help get the shape & function in mind:

So - what do you think the best way to approach this would be? If it’s even feasible?

I am thinking some kind of core material for added strength & rigidity, and a thick layering around the mounting/hinge points. The other thing that seems kind of tricky to me is that it must be build up the opposite to how something like a body panel is done. For example I can’t see any way you can use a regular mold for a part like this??

But then again I have very limited experience, so I’m hoping that someone can help me learn something!

Cheers

#2

I think you might be better off with a Ti side stand…

#3

A composite tube with a thick enough side wall should work well in this application. You’d just need to work out how to create the tube.

#4

I would build the thing from fiberglass before I’d build it from carbon. The higher strain and toughness of glass will be more durable if the bike gets laid over.

#5

I think a simple thick walled carbon tube would be fine. All depending on fabric and method, 1/8" thick might be fine. Need lots of uni. Maybe ALL uni except the inside and outside plies. I think carbon will hold up even in an accident…it’s flexible.

#6

I don’t think the strength of holding the bike up is something you should worry about, it’s the crashes that is going to shatter it. I would seriously stick with stock. Pick something else to lighten up like the airbox.

#7

Personally if you are gung-ho on this project you can approach it the same way that I built a CF subframe.

Buy tube stock
machine a pivot end and bottom plate from whatever material you like (i used 6061-t6)
bond the two pieces to the tube and call it a day

#8

Thanks all for your replies.

Glad to hear that others have gone the CF tube stock route, I got to thinking that it would be the least hassle…

As it happens I have had some other work for this bike done at a local tooling shop, I think getting them to make the mounting plate and stand base will be the way to go… I’m going to think about it and will post back if I end up doing it!

Also this is not for weight reduction or anything like that, it’s simply because I don’t have a side stand to begin with! Sure, I could buy one for $140 or so, but I figure that I may as well use that money to build my own - and learn something along the way!

I’m not too worried about it getting damaged in a crash… crashing is well outside a motorcycles design brief, so things are going to break anyway! And I haven’t crashed in a few years, I’m out of that newbie stage… although it’s interesting that there’s so many different opinions about how the CF will hold up in a crash…