[Driving] Homebuilt Locost 7 - from Motorcycle engine to Leaf power!

[Zieg]

Yeah I made a spreadsheet somewhere but the other problems I discovered is availability and the limita of my crappy ram-type pipe bender. The 1/2" ram did ok bending a scrap of 3/4x.120 but when I tried .065 it just kinked. Grabbed myself a piece of 3/4 sch80 that I can bend and then cut out the inside of the bend to sit as a spacer in the die and better support the tube I'm bending. I have a random 8ft length of solid 3/4 that I can try, and I just bought a length of the same .120 size DOM I've been experimenting with.

Clamping the bar would be ideal but I don't think I have enough room. I have a 1/2" male heim joint screwed into a female one and that's about as long as my endlinks can be. Planning to just swap the bolts on the shock mounts with longer ones and attach the endlinks there. This also lets me attach it on either side of the shock body for more adjustment possibilities. I tried flattening the ends of my scrap tube with a 10ton press and it worked, but looked like ass. Will try once more with some makeshift dies, then plan B is to weld some flat bar to the bar, I guess? Seen some like that on google.

The other idea I had was to maybe use a heim with a 3/4" bore and slide the bar through it, holding it in place with some locking collars. Any thoughts on that? It would also mean getting a 3/4" female heim and making some kind of stupid threaded bushing so I could still screw the 1/2" heim into it. Or, I guess, use 3/4 heims top and bottom, with a bushing through the bottom link's bore so it would fit the 1/2" shock bolt...

[jrbe]

I'm not sure how it will do if you try to skip the hardening process / material. Maybe this is light enough to not be a big deal but I'd expect it to go soft over time. Maybe in 5 turns, maybe 10,000. Not sure you were thinking this way.

The 3/4 bore heim sounds good but it will be sensitive to coating thickness, nicks, etc. May not slide well or will be tough to get to a good finished OD I think. Maybe zinc coating the adjustment ends could work if it's really smooth..

You could also go with a splined bar with splined arms and bend the arms to fit if needed.

If theres somewhere else to attach to it may help the link situation. It's tough with very little room to adjust and the unbolt it to adjust it is a pain. You can also adjust at the swaybar bushings if you leave yourself room with their brackets.

[Zieg]

Well I've seen some kits with just 1026 DOM tube, which is what I bought. It's also recommended on some Locost forums so hopefully it holds up. I did run a quick calculation of shear stress at max deflection and it seemed ok. I guess welding close to the twisting part of the bar is still not ideal though, so I will avoid that. Splined would be cool but the only kit I found in my size range was NOT in my price range. I guess I could just mill a couple flats onto the tube and have the ends laser cut or something? The formula-style rotating blade swaybar ends would be amazing, but I can't find those easily either, and I know they are expensive.

Thought about mounting to the upper A-arm instead but I don't think I can do it. Both links are adjustable so it would have to attach to the ball joint cup, which is inside the rim and the cycle fender frame already gets close when turned to full lock.

Easier to make a short video than try and annotate photos, this is my attempt to explain my current plan.

[jrbe]

The video helps a bunch. Some thoughts after watching it:

Can you mount the bar inside the frame? Limits arm length though if that's already an issue.

The upper ball joint looks ideal to use for the link point if you can mount to it / if the upper ball joint can deal with added force in the vertical direction. The fender mount may work well too. One thing to watch for is jacking at the swaybar from steering inputs. You can use this to your advantage if it goes the right way.

The longer the swaybar link the better the angularity / the more linear it travels as the suspension moves up and down.
Mounting the swaybar higher and using a longer link down to the lower shock mount may work out best because of how things are configured. Should avoid jacking from steering and should allow longer links with jackscrews / turnbuckles. It also looks like there's the most room for this in the video but I'm not sure what's going on radiator wise and other stuff up there.

If the mild steel goes soft over time, you can copy it in a hardenable steel. And if you search out individual pieces splined swaybars can be had under $200 or so in common lengths, especially second hand.

[Zieg]

Okay, good point about mounting it on the inside of the frame. I thought that would have it too close to the pivot point but on a second look, it's actually better. Thanks for that (and all the advice and input). I cut the bottom part off one of the cycle wing brackets and it is going to need to be reinforced, but I was able to extend the heim joints basically right to their minimum engagement. There's only 2" of travel in each direction so hopefully the links are long enough like that.

There's just enough room to fit the 3/8 bolt in the hole. Debating just welding a stud in there, but I think the bolt will be ok. And I don't have to move the rad fan! The one on there is a cheapie from ebay and I don't know if it's actually reversible. Not having to touch it is nice.

I guess the other nice thing about it being on the front is that if I don't go stiff enough, I'm really no worse off. Anything will help a little bit. And if some how it's way too stiff the car will understeer but shouldn't be dangerous or anything. The other good news is these bushings are cheap and have a common bolt pattern.