LocostUSA.com

Motorcycle rear shock with the eyelet on the shaft end threaded off:

Can I build a thread-on end that mounts like a MacPherson strut would?

The application at hand has limited vertical space. I intended on using Rabbit strut cartridges and coilover sleeves:

But even they are a bit longer than I hoped, and I still need to build the part that mounts to the spindle.

Instead of having to shorten the Rabbit strut cartdridges, I would like to use the motorcycle shock but am uncertain if a shock can handle the same loads that a strut would take. Also, I've never handled a motorcycle rear shock; are they of a significant enough diameter to compare to standard strut as far as lateral loads are concerned?

I don't think the cycle shocks could withstand the side loading a Mac Strut sees and would wear pretty quick.

Cheers, Ted

Unless someone's already tried it and proven it lasts, I think the only real answer is "no one knows." The side-loading issue is a big deal, not just the bending on the shock tube, but also the shock absorber shaft bearing which was never designed to deal with those loads.

_________________
Midlana book: Build this mid-engine Locost!, http://midlana.com/stuff/book/
Kimini book: Designing mid-engine cars using FWD drivetrains
Both available from https://www.lulu.com/

maybe a good one, maybe... that particular cheap OEM pos? neg.

Quite a few people that I talked to today on an application specific forum said that shocks can't handle the sideforce and mentioned aluminum vs SS parts, but haven't seen any hard evidence, though I believe it.
I was considering something nicer than the disassembled unit, but still OEM (Monster, R6, GSXR); however if the shock can't handle the side force, it doesn't matter. This morning, I looked at a couple ATVs and Snowmobile and their shocks were far too small for my application (14mm shaft vs a Rabbit's 19mm), but suggested to me was front ATV struts as they are just a small MacPherson strut. I'll be looking into this.

A shocks side force is higher than people imagine and a struts is lower than people imagine - does that help?

Compare the shaft, piston and bush size is the only way to determine what they can stand, it's not a given either.

You would be better considering adapting bike front forks maybe.