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Hello from Canada - DIY padded seat for rear rack

Started by Banjopete, September 04, 2023, 10:01:17 AM

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Hi good folks and fellow bikists. I broke the frame on my trusty commuter last monday, leaving myself in the lurch so naturally I made a rapid decision and find myself the owner of a rad! wagon.

I'm a little leery from the reputation of the tires but I needed something to get me and my 2 kids to daycare, and myself to work with.  We've made the transition from kids in chariot, to kids on bikes of their own, to winter short truck ride to daycare, and now potentially all of us on the wagon all year.

Radpower's out of the padded cushions for the seats at the back but I've got access to some tools at home that can hopefully make quick work of the DIY job.

So far I've got the plates cut, and am planning on using some garden kneeling pads for butt cushions for the kiddos. I'm comfortable with the woodwork, and metalwork, less so with the upholstery work but only one way to get better.

Here's where I'm at right now.

I've got a bunch of the accessories coming with this thing any day now to speed up the kids on the back way but I think I could've had some fun making up some handlebars, pegs, racks etc still if I'd been a bit more patient. Anyways I'm excited, and looking forward to sharing ideas, and hearing from all your experiences with these things.


I liked the last two images. A little more expensive than kneeling pads but it looked cool.
Literally is LITERALLY the most annoying word of the decade.


Quote from: Naranja_CT5+ on September 04, 2023, 01:11:19 PM

I liked the last two images. A little more expensive than kneeling pads but it looked cool.

Yeah there are lots of neat ideas, seat backs would be pretty nice too. I do like the attachment method for these accessories and would way rather be working with bolts into the frames than clamps. I'm sure I'll appreciate how modular these can be with some use.


Well I wrapped it up. I'm pretty happy the way it turned out, and so far my kids are pretty content with the butt pads. It may not be the final version but it's a working copy for the time being.

Just some 3/4" baltic birch cut to fit, with the kneeboard/pad cut to match, then wrapped in some heavy fabric. I bolted the pads down from the top using the conveniently already threaded holes, then plugged the holes through the fabric/pad and wood using some 3d printed plugs that still allow for the squish in the seat.


Shucks Ma'am, I'm no "Hero Member", I just like to wear this cape.


Does anyone have any experience with using a longer seatpost for these things? I'm 6'3" and long in the leg, and despite the fit, I'm much lower on the seat than I've been in a very long time on any previous bikes.  Any chance someone's successfully used a much longer seatpost without damaging the first sleeve or the frame?


Quick success on the seatpost front, I've added a 400mm 30.9mm seatpost that fit perfectly. Way better for riding now that my legs can stretch out once more.


I don't think setting the seat post at a comfortable height will be an issue for you.

I believe on the RW4 one could even be 7 feet tall and still get proper leg extension. I'm only six feet but I have a 34 inch inseam and I have the bottom sleeve set very shallow. With the standard seat post and the scale on the back of the post I had it set at about 6.5 whatever that is. None of the two telescoping devices were close to the minimum insertion depth.

FWIW I just installed a 27.2 Suntour suspension seat post on my RW4. I used a 30.8 sleeve (the bike shop didn't have a 30.9 sleeve) for the 27.2 seat post and it's working fine. I've put about 30 or 40 kms on it and it is holding position. I'm not sure why Rad's web site says the Suntour seat post isn't for the RW4 as they simply need to have a few sleeves in stock.

It works excellently. Very enjoyable riding now.


Quote from: Ddaybc on September 16, 2023, 08:11:28 AM
I don't think setting the seat post at a comfortable height will be an issue for you.

I believe on the RW4 one could even be 7 feet tall and still get proper leg extension.

It's a strange thing indeed but something about me and bikes has always resulted in massively exposed seatposts. In stock form on the RW4 I felt like I was close to 90 degrees at the knees at the bottom of the stroke. Maxed the minimum insertion height on both sleeve and post.

I've got a 400mm post in now and I think I could still go to 450 to get closer to what I'd usually set it at. So I'm maxing out the min insertion lines on both sleeve and new post. It's still not perfect but it's much much better than before. Just a strange body I guess, and I've always had long legs. 6'4 and I don't even look at pants unless they have 36" inseams or more (shoutout lululemon's 38" inseams!!).

No big deal, I expected the one size to fit all to be a challenge to adjust to.


You've got a 400 mm seat post maxed out? I think you're right, you may need a 450 mm post to get proper leg extension. I note Rad's web site indicates the RW4 is suitable for riders with an inseam just over 36" but I'm not sure how they measure. Bike fit is such a personal thing.

Good luck and keep trying to find a good fit.


Well I've got the tires mounted up. They're pretty beefy looking, and went on without as much fuss as I thought they would. Pretty much just my hands and body weight to wrestle them on.  I swapped to some new tubes while I was at it as well.  Hoping these are durable and grippy for the kilometers ahead.


Banjopete, those tires look great. They appear to have lots of tread blocks of sufficient depth so one could also stud them if necessary. Of course they will affect range and speed but one doesn't use something like a RW4 for speed or usually range. Most ebike riders often don't even go 20 miles (30ish Kms) per day. Hopefully you will be fine.


I went out last night with my family, two kids on board and did a 20km round trip for ice cream. These tires are noticeably slower, significantly so, much more rolling resistance felt like the bike was dragging the whole way. PAS felt like 2 less, so 3 felt like 1 and so on. I didn't check tire pressure but think first thing I'll try is a higher pressure and see what that does.

I knew this would be a thing going in, but wasn't quite prepared for how big a change it made. Ride wise I can feel the additional load rating of the tires, the ride for me and passengers was more supple while also being a lot stronger. Bumps, and curb ramps etc felt a lot smoother. I'm a hopeless upgrader and already am thinking a bigger motor and more batteries would be the ticket haha.

John Rose

@Banjopete :
Is that houndstooth an upholstery fabric or some kind of waterproof vinyl?

What did you use for the clear plastic sheet fastened to the fender? Some kind of Lexan / polycarbonate stuff? And where did you get it?

RadMini ST 2 / RadExpand 5


Banjopete, when your Kenda tires arrived, other than an arrow showing which direction they are supposed to rotate, did they have any markings indicating Front or rear? I'm still divided between ordering one for my front wheel verses the tire chains from Slipknot Traction.

Thank you.