What size is the ELF frame tubing?

[Projectitis]

Hi all,

I could hunt down a local ELF owner and take a few measurements myself, but I'm in New Zealand and I'd be surprised if there was more than a single one in the whole country

I've found several photos (attached), some nice quality, of the Organic Transit ELF. However, it is difficult to get any reference for the size. I'm trying to determine the aluminium square tube size that OT have used for the various structural members, most notably:
- The two that run aft alongside the rear wheel
- The main fore member that holds the bottom bracket

At a guess I would say the two rear are 40mm x 3mm (or 4mm) and the front is 50mm x 3mm (or 4mm), but because the ELF is so big, the size in the images may be misleading. Also, the bottom bracket goes right through the front tube, so 50mm might be too small. Then perhaps they are 50mm and 60mm respectively?

I'm building my own trike (not ELF) and thought using the same size tubing as the ELF would be a pretty safe bet.

Rather than guess from the photos, are there any ELF owners who could take a few measurements for me?

Much appreciated!

 

[amberwolf]

Is that regular bike chain? If so, then you can see how long each link is, and use that as a reference for the tubing next to it.

Then you can use that tubing's other end as a reference for the rest of the tubing where it joins together.

 

[Projectitis]

That's a good idea. Still just a guess though
I'm hoping there is an ELF owner who can help out!

 

[nerdalert]

That looks like 1.5"

Are you making a vehicle similar to the ELF? Me too. Was looking around for projects to see if anyone had done an enclosed electric bicycle that was worth a damn and found this thread. I am many hours into mine already. It started out as an original idea and went from there. Will post a project log.

 

[Projectitis]

Yep - exactly what I'm doing. I wouldn't say "similar to an ELF though" Mine will be an electric assisted trike, but that's about where the similarity ends! I'm also a way in to mine. Have parts coming by boat from China, and currently working on the plug. Getting the body shell made in carbon fibre by a local company who will pull moulds off the plug.

My point of difference (i.e. The reason I'm not just buying something that exists) is all about style I'm going to be trading off some weight and performance for comfort and good looks. A higher seating position, retro design, convertable soft top, leather interior. I.e. Not utilitarian like the ELF, friendlier to the average rider than 'classic' velos like the Quest, and much more comfortable than most of the builds I've seen so far, though there are some really cool one-offs if you spend enough hours on Google.

Not ready to share specifics quite yet, but will surely be doing so in the not to distant future!

 

[Projectitis]

Will post a project log.

Look forward to it!

 

[WoodlandHills]

What alloy did ELF use? There is a big difference between 7075, 6061 and the 1000 series. Get the alloy wrong and the tube size won't matter........

 

[Drunkskunk]

The front half looks like 2.5", 1/4" wall tubing, the rear looks like 2", 1/4" wall. hard to say, and I'd bet it's actually metric sized tubing.

It's 6061T according to ELF's website.

Got pics of what you're building?

 

[Projectitis]

Yeah, as drunkskunk says, they use 6061 T6. Real difficulty finding anyone that stocks it here (New Zealand) and mill runs need to be at least 200kg per size, so not feasible. I'll likely end up using 6060 T6 which is less strong, but still up to the task, especially as the frame will be over engineered anyway.

Still finalising the model, but to get an idea of what I'm building, just think of a bicycle version of the Brutsch Mopetta microcar

The main difference is that there will be two steered front wheels and one driven rear. And electric assisted pedal rather than 50cc petrol, obviously

 

[nerdalert]

Using bumper car?

 

[Projectitis]

Haha! Looks a bit like one. Nope, pulling moulds of a CNC milled plug (hand finished), then carbon fibre body shell for stiffness.