Gotcha, I’ll try installing it on the shaft later with my invisigoggles on and antimatter hammer.
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Any ideas on how the fuck to get this tyre on the rim without spending a fortune on tools?
So far I’ve tried dish soap on the rim and bead, and brute force but no luck. Ordered some metal tyre levers which should come tomorrow. Lots of people the interwebs reccomend getting some tyre tongs but they cost like 60 quid and payday is too far away to justify that.
I asked my dogs but even theyre out of ideas. Oscar came to investigate whilst I was looking defeated (yes I did attempt to film me fitting the tyre. No it wasn’t successful) and Berkley is just fed up with the whole ordeal and wants a solution so he can get back to sleeping.
They are demanding answers immediately.
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Tire levers and soap are usually enough. If not, I’ve heard good things about the Big Zip Tie method. By brute force, do you mean hand pressure?
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Hands, knees, feet, toes, you name it. Ive tried every appendage my body has to offer.
Whats the big zip tie method?
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I haven’t actually tried this method yet but this is how I planned to get my gokart tires onto my rims eventually.
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Ooh thats very clever, I’ll definitely have to give that a go. Although with my luck, the lever will slip from under my feet and render me infertile before whacking me in the face.
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It’s easier if the tires are hot and malleable, leave them in the sun before installing. You want a good angle between wheel and tire when installing so you may need to fold the tire to line up with the inner groove of the wheel once you’re on the second bead.
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Sun? Might as well wait 6 months 
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Mission success!
Here’s how I did it:
- Spray the rim with a 50/50 mix of dish soap and water then attach a clamp from sidewall to sidewall of the tyre. (Make sure bead lock screws are fully undone but still in the rim)
- Attach another clamp about 90° from the first
- Tighten them both down until the beads on both sides are within the rim.
- Tyre lever approximately 30° from the first rim until the bead is in place.
- Tyre lever approximately 30° from that and repeat.
- Keeping both tyre levers in place (i used my knee on one and one hand on the other), add a third tyre lever approximately 30° from the last one.
- Remove the first tyre lever, hold the other two in place and place the new lever 30° from the last one.
- Rinse and repeat.
- Pumped up the wheel using a bike pump
- To set the beads, i used a combination of air pressure, a mallet and a heat gun (thanks for the tip @Titoxd1000) around the rim.
- Tighten bead lock screws.
The tyre is labelled tubeless so I hope it stands up to that claim othwrwise I am absolutely dreading having to remove this motherfucker.
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Been doing a little more work in CAD over the last couple of days:
I know this looks like slow progress, and you’re probably thinking “why the fuck is he re-modelling the same things over and over again” but I like to take a slow and methodical approach…sometimes giving things a few days of thought before taking the next steps.
I’ve been playing around with the battery shape/size/enclosure. I think I’ll go with a 20S2P Samsung 40T pack (I know the cells aren’t exactly top of the line but I’ll work with what I’ve got!)
I need to work out what shape it’s going to be. I’m thinking 2x 10S2P packs in series with insulation between them, where each pack looks something like this:
Yep, I’ll be using cell holders. I bought them for the mountainboard build that’s fallen through, but I figured they’d be great here for the extra rigidity as flexibility isn’t necessary.
The crossbars between rails will be aluminium extrusions. This gives me a nice cheap and easy solution for mounting the footpad on top as well as mounting a 3D printed enclosure to house the electronics.
This is a really rough mock up of the aformentioned printed enclosure:
There will be a gasket around the top edge and the footpad will also act as a lid for the enclosure.
I like the way this is going. I’m debating making both of the lengths of extrusion 2020 to give me more room inside for the electronics but we’ll see. Ideally I’d like to keep that 2040 extrusion close to the wheel to counter any torsion in the frame.
Biggest concern right now is routing cables front to back. I think I’ll probably copy @lock approach. I know I said I would route them through the rail, but I’ve decided to replace the bearing retention circlip with a plate to simplify machining for my friend who will be making the rails:
Also the keen eyed among you will notice I’ve changed the shape of the rails a little. Nothing major, mostly aesthetic:
I’ve also made the axle longer. After modelling the tyre with dimensions more accurate to what I have to hand, it’s now 220mm long to give plenty more chain clearance, making the total width of the board 234mm which is just where I’d like it to be.
So, next steps are:
- Design the battery.
- Order the BMS and take measurements to help electronics enclosure design.
- Design the battery enclosure, making sure not to forget the waterproof gasket and cable routing…
Stay tuned for more updates 
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Haven’t heard from you in a while, any updates?
I bet over the course of this many times you have considered making one/both of the rails super thicc and hiding the chain drive inside the rail sorta (huge cnc cost if 1 part rails and not sheet metal fab or other)
Yeah I have considered many options for making XR rails wider while somehow needing minimal mods to bumpers, footpads etc stuff that is annoying to make also readily available. Normally this would just be to fit 20S2P huge battery (gt-box) packs on “XR platform” Only need an extra 5mm-10mm max or so in width. That extra width in this case would help a ton with getting the chain away from the tire sidewall.
I see your custom rails so far don’t really have footpad and bumper holes market yet. Do you want CAD models of other WTF style XR rails? you could get the hole pattern and try using some of it.
After writing I did see this topic you did cover. I imagine putting the cross bars in the right place would allow XR footpads to be used. If you end up with flexible footpads on this thing you may have a metal plate over this area so that might be something to consider any advantages you could find in it.
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If my budget was infinite… but that would also increase the width and probably the weight a lot too.
If you’ve got em I’d appreciate it!
Thats not a bad idea at all, i was going to make a custom footpad but might make my life easier to use something OEM.
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Hold onto your socks
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Great response, this gearbox/chain reduction hidden within the rail dream is how I imagine FM would make a board like these. I love the idea of removing part of the non gearbox rail and quick swapping cheap hubs/tires, like a giant esk8 drivetrain. This is basically the only way it occurs to me to get a fully sealed gear reduction, at least with chain.
Yep unless you really want to try to diy fp, some used TFL kush pads would speed the build up and save future foot pain. With a smart 3d printed TPU filler part I think it would work well even with a wider board than XR.
The XR/BANG bumpers would not really work good with widening. My idea of sawing them down the middle and bolting back together with metal is sketchy.
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The other method would be to mount the motors directly above the wheel with a sealed gear drive transmitting power vertically down to the axle but it would be much more difficult to design imo
Thanks for the cad files theyll be super helpful 
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one more unique chain gearbox idea to consider… sadly a 6in rim is just barely not enough room to make that easily. It would push towards using a super wide hub/tire so that would look amazing!
I realize if this chain drive broke it would instantly lock up… ouch. (although any sealed chain drive would too)
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Awesome work @That_Jamie_S_Guy . I haven’t posted in a year, but I check in occasionally because it’s one of the best forums full of people building cool stuff.
Much of what you’re doing is what I was thinking for a v2; rely more on off-the-shelf kart parts and a switch to chain drive. Belts are too wide, and getting the necessary reduction is harder. I probably would have stuck with a single motor likely something larger and higher KV, the kind of motors you’d see ElectricFox testing out in actual karts. Unfortunately not cheap.
I can appreciate it’s hard and slow doing this kind of project without a machine shop. Caused me all sorts of compromises; like there’s better ways I could have designed things, but I’d never be able to manufacture it.
Anyway, just wanted to say great progress, and I’ll keep checking in to see how it goes.
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