Think the problem with the trike is when you add a proper drop out for the other side of the hub that bit of the "for" hits the frame and limits the turning circle.
CityCyclingEdinburgh Forum » Questions/Support/Help
Xyz spaceframe reumbent trike
(82 posts)- Started 3 years ago by steveo
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Posted 3 years ago #
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@Laidback, if steveo doesn't take the hubs, could I have one of them please? I don't need a pair.
Posted 3 years ago # -
/vultures begin to circle
:D
Posted 3 years ago # -
@steveo, I'm not au fait with the trike design, is it one wheel at front or two? I can imagine steering with two up front is a tricky build task with precision required...
One of the few tricky challenges when building the trailer was getting the dropouts lined up so the wheels spun freely and true. Of course they don't need to steer anything, but they still need to track properly otherwise trailer will keep dragging and trying to tip itself over.
Posted 3 years ago # -
Hubs are at shop @steveo / @arellcat - in Sat for collection. Not that common an item.
Trailer is of course easier option to build so using disc brake ready hubs not required. The ICE Sturmey Archer 90mm wheelset includes brakes which is good solution for trikes. Heavier rim and wider hub too. Atomic Zombie was a site that had plans for all sorts of stuff.Posted 3 years ago # -
I'm pretty sure I'm going to have a go at the cargobike so if @arellcat needs the hubs I'm sure her needs are greater than mine.
Posted 3 years ago # -
So had another look at the photos and the cargo trike and bike share the same chassis.
Ordered a load of aluminium tubes and fixings should arrive in a few days.
Planning to build the bike first as its easier to store and get out the driveway but also because it doesn't use any uncommon parts. The steering looks a bit pernickety with a funny "fork" so if that fails it should be relatively simple to remove one steering system and replace with another.
Posted 3 years ago # -
"...and replace with another."
Feet on the backs of the front wheels, or a lever-operated spoon brake if you were being fancy.
When I bought my foot-scooter I went for a version which came with pneumatic tyres, then promptly got a set of solid wheels after a couple of punctures, so am currently considering if bits of old bike frames and forks and spare 8" scooter wheels can be persuaded to speak to each other and form part of a low-speed shopping-trolley-like trailer.
Posted 3 years ago # -
I'm on the scrounge...
Has anyone got a 26“ rear wheel or a 20" front wheel? Quality or even functionality doesn't matter for the moment. I can probably scrounge a 20" wheel from the kids.
I've examined a load of photos and decided the best way to proceed is to work back to front and place everything relative to the back wheel in the first instance, the handlebars will be relative to my biometrics. The cargo box size is fairly arbitrary and the fork is pretty independent of the main chassis as it bolts on to the cargo box.
But to start I need a 26" rear wheel.
Posted 3 years ago # -
Found a 26" wheel. In my garden under a load of knackered 700c I stripped down to get one working one. I really need to get my garden cleared out.
So looking for a 20" so I don't have to strip down the kids bikes!
Posted 3 years ago # -
"I really need to get my garden cleared out."
That reminds me, my lockup is well overdue for a clearout...
I probably have a 20" wheel somewhere, alas I expect I'll be unable to find it in the burach...
Posted 3 years ago # -
If the plan is to work back to front its going to be long time before I need one. The boys bike might need refurbished before that...
Posted 3 years ago # -
That's good. Because I have to clear out the spare room, weed the allotment etc. before getting to the lockup... Could be some time.
Posted 3 years ago # -
Made some progress today. Built the rear "drop out" and worked out where the seat post is meant to go.
Spent some time making the various connecting bits but in hindsight with out a chop saw and drill press its not accurate enough so I'd have been better clamping stuff up and then drilling out for the bolts. Frame may end up a little small but I had 2.5m lengths seemed to make more sense to make them 1m and 1.5m.
Posted 3 years ago # -
Having said that it has just occurred to me that the frame has a axle width of 125mm on the rear this is likely to be far too narrow for modern gear. I shall need to meditate on the problem.
Posted 3 years ago # -
CCE hive mind I beseech thee...
How can I attach a saddle to a tube of aluminium 25mm square section?
I've got the "seat post" constructed and adjustable bit slides between two sections of aluminium clamped down the by a bolt or qr. I've seen old style seat rails that clamp on a seat post with out rails but these all seem to be bigger than the 23mm internal section I've got to work with.
Xyz seat tube https://imgur.com/gallery/yzxZF6T
Posted 3 years ago # -
Can you not just use a normal seat post? Maybe a fairly long one? Drill holes laterally at a couple of points to bolt through to your seat "tube"? If the bolt fit is snug enough, should be fairly strong. Add washers/spacers on the outside to ensure even compression.
Posted 3 years ago # -
Here's one that may be suitable.
Posted 3 years ago # -
Cheers crowriver, I'd considered bolting it through but I'd lose the adjustment. Probably wouldn't be an issue on the other hand I'd have to get the fit right first time!
Posted 3 years ago # -
The clamp per the classic USE seat posts might be of use. Solid bar front to back and more or less horizontal, 2" piece of thick walled handlebar split lengthwise for the lower saddle rail seat, but you would need to fabricate the two upper rail clamps. M5 bolts to hold it together.
Posted 3 years ago # -
@steveo, you could have a bunch of pre-drilled holes in your square profile tubing, thus allowing for height adjustment (with a bit of faffage) as required? Could be in 1 inch increments. For lateral adjustment and pitch, if you use a "classic" style seatpost then a suitable "classic" seatpost clamp can be fixed to the saddle rails which should be highly adjustable.
Like this:
Posted 3 years ago # -
Thanks guys, I'll ponder.
As an aside wow USE seat posts are expensive!
Posted 3 years ago # -
I did once have an old saddle-clamp saddle and seatpost lying around but they might have gone back to the Bike Station years ago. I'll check the shed/loft...
Posted 3 years ago # -
So I was having a think. The square tube internal dimensions are about 21mm there is a saddle clamp like above for 22.2mm.
What about getting a 21mm tube, maybe even a small length of stainless for the strength, and shimming the top of the tube to fit the seat clamp?
Or get a 7/8" tube and file down a 100mm length to fit the 25mm square tube.
Posted 3 years ago # -
Judging by N55's image here, and the images on cargobikemag, there is some piece of seatpost banged into the square section.
BMX seatposts are traditionally 22.2mm throughout, so you can use a conventional seatpost clamp on top. I'd probably buy one and chop it down to four or five inches long, file some flats on it to bring it into size for the square tube, and either cut a traditional slot on the rear of the square tube to match with the primary QR clamp arrangement, or make it a sliding fit and epoxy the post into the square tube.
Posted 3 years ago # -
Yeah, you can (just) see here that the seat post is inside the square profile tubing. Presume the whole thing moves up and down for vertical adjustment and is clamped by the other square tubes sandwiching it against the flat plate aluminium?
Then a "classic" seat post clamp to hold the saddle.
Posted 3 years ago # -
Thanks @arellcat I missed the photos in the second link that confirms your thinking.
I reckon I'll epoxy the seat post into a square tube then adjust using a qr in the other two square tubes to clamp it up.
@crowriver yeah I missed that the first time I looked over them. I've tried clamping a square tube with those back ones locked down and it's pretty tight!
Posted 3 years ago # -
Thinking ahead. Any safety concerns using the same approach for the handlebar?
Posted 3 years ago # -
The bottom bracket assembly went as well as expected. Really badly!
Even with the plates held together the hole is on a slight run and when I space it out across the frame the bb is quite badly skewed. Plus the 35mm hole saw is too big so the bb just slides in and out, the threads are no where near the plates.
My options as I see it are,
A) pay someone to cnc it
2) buy a bb shell for frame building (which won't help it being skewed)
Iii) get access to a drill press and a hole saw much closer to the size of a bb.Posted 3 years ago # -
A²: acquire an old frame with an intact BB shell and brace the chainstays and down/seat tubes against other things.
Posted 3 years ago #
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