20" bicycle rim / 16" moped rim, 50mm+ wide

amberwolf

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So:
https://endless-sphere.com/forums/viewtopic.php?f=2&t=67833&start=1000#p1595873
:(

I'm out of rims for the rear wheels of SB Cruiser, and need to buy at least one new one (might as well buy at least a pair while I'm at it).


So I'm up for new rims, as affordable as possible, but also strong. I'd be ok with steel ones, too, since I could bend steel ones back when the edge gets dented or crushed when I hit unavoidable sharp-edged potholes (infrequent, but it destroys the aluminum rims when that happens--they cannot be bent back, or they will fracture and fail dangerously--I have to leave the dents in, which means the tire doesnt' seat properly in those areas).

Presently I'm using Shinko SR-714 x 2.25" moped tires. I'd use the 3" version (80/90 or 90/90, IIRC) if I could; would require rebuilding some of the trike rearend / fender frames to accomodate the width, but I'd do it if it improved the ride quality some (larger air volume). Would probably work better with a wider rim than I presently use (50mm).

I'm using moped tubes, with all-metal valve stems that are secured to the rim by nuts--so a rim that has an inset for this on the inside surface (where the tube sits) would be nice; the ones I use now are typical double-walls that dont'.

I'd prefer something built for smaller spokes / nipples, as I use the Grin Tech Sapim 13/14g butted spokes, which have 15g-wrench flats and 14g threads. I expect I'd need to use washers if I use a moped rim, as they'll likely use larger spokes normally. A bicycle rim would work if it's nice and strong.

I'd prefer eyeletted nipple holes if it's aluminum, to minimize stress cracking and pull-thru. Guess those aren't needed on steel rims.




Separately, I am also looking to build a completely new trike, which would use much larger diameter rear wheels, probably something like pedicab wheels, dont' know the diameter but the larger the better to roll over road problems without suspension. Suggestions on those would be useful as well. (I need to look up Chalo's posts for the ones where he mentions where he works and builds those kinds of wheels, and maybe just buy some from there complete). These wheels would not have hubmotors in them; the motor(s) would chain drive them.
 
I think you're better off modifying the rear end to support wider wheels. Of course, it's the harder solution but it's ultimately simpler and more practical.
Replacing rims like that is surely more expensive (and mainly troublesome) in the long run, no?

After you do that you can use fat bike wheels, get the chunkiest 20 inch rims you can find. Most of the tires you'll find are for beach cruising and snow, but there are some beefy street tires too, little more expensive, see "Innova 5189". Even if you opt for cheap tires, traction might not be superb but you'll still get a very cheap wheel with much better weight carrying capabilities.
 
The very strongest, heaviest freestyle rims (e.g. Alex Supra E) are all out of production, so you'll only find them as old stock or salvage. Some people consider this stuff collectible, which hurts price and availability.

Others include Alex Supra RX, Peregrine Mad Max, Sun Big City, Odyssey Hazard, Gsport Ribcage. I'm sure there are many others in the same category I'm not remembering. But 20" freestyle double-walled rims over 30mm wide and over 550g are all going to be pretty good.

If you can make it fit, a double walled, non-windowed fatbike rim is your strongest option, probably even more so than a moped rim. But then you'll have to use fat tires.
https://www.jbi.bike/site/product_details.php?part_number=47970
47970.jpg


Based on my experience with putting 2.1-2.5" tires on 65mm rims, I think a 3" tire would work just fine on a 100mm rim. That opens up some decent options.
 
goatman said:
grin sells them
https://ebikes.ca/shop/electric-bicycle-parts/rims/rim20-fat.html

That's new to me. Good find. New first choice
 
goatman said:
i use that weissman fat rim from grin but in 24 inch with dual gauge spokes at 3000 watts and its been excellent
I've used that rim in 26" and 29", for hub motors and pedicab wheels, and it's as good as I've found for heavy loads. I didn't know there was a 20" version.
 
BDamari said:
I think you're better off modifying the rear end to support wider wheels. Of course, it's the harder solution but it's ultimately simpler and more practical.
Replacing rims like that is surely more expensive (and mainly troublesome) in the long run, no?

Yes, but this trike (SB Cruiser) is presently my only transportation. Unfortunatley at the rate I'm completing projects after getting sick early this year, between the dayjob and exhaustion, I would have to first build a new trike, or put Crazybike2 back in operation, before I could modify the SB Cruiser trike--it would probably take me weeks (at a minimum) to do the complete rebuild of the rear end of the trike to accomodate different wheels than it presently uses, and I cant' be without transportation more than a couple of days at a time.

Right now, money is less important than time (I have a little spare money, but not really any spare time at the same time as I have energy).

Just relacing a wheel takes me a day, sometimes two, instead of an hour or two.


After you do that you can use fat bike wheels, get the chunkiest 20 inch rims you can find.

If I *were* to rebuild the back end, I'd go with 29" wheels, because I'd get a MUCH better ride out of them, as long as tires at least as tough as the Shinko SR214 2.25 tires I'm using now are available for them at a reasonable price, and 3-5mm thick tubes are available for them for a reasonable price as well.

Even if you opt for cheap tires, traction might not be superb but you'll still get a very cheap wheel with much better weight carrying capabilities.
Traction is essential, so can't be sacrificed. I can't have the back end sliding around on the road, nor having the wheels skid during typical braking.
 
Balmorhea said:
The very strongest, heaviest freestyle rims (e.g. Alex Supra E) are all out of production, so you'll only find them as old stock or salvage. Some people consider this stuff collectible, which hurts price and availability.
I couldn't find any actually in stock anywhere, just searching on the name. :(

Others include Alex Supra RX, Peregrine Mad Max, Sun Big City, Odyssey Hazard, Gsport Ribcage. I'm sure there are many others in the same category I'm not remembering. But 20" freestyle double-walled rims over 30mm wide and over 550g are all going to be pretty good.
I'll look around and see what I can find in the 50mm size or wider (up to 55-60mm, *maybe* 65).


If you can make it fit, a double walled, non-windowed fatbike rim is your strongest option, probably even more so than a moped rim. But then you'll have to use fat tires.
https://www.jbi.bike/site/product_details.php?part_number=47970
https://images.jbi.bike/800/47970.jpg

Based on my experience with putting 2.1-2.5" tires on 65mm rims, I think a 3" tire would work just fine on a 100mm rim. That opens up some decent options.

If I had room for 100mm rims, that'd be great...but I think 60-65mm rim would be pushing it, and I know I couldn't fit a 3" tire without modifying the frame around the wheels. At minimum I would have to cut off the wheel well frame and rebuild it, which under normal circumstances would be a few hours, maybe a day, to do...but right now would be at least several days complete downtime for the trike. Can't do that now...earliest time maybe after newyear's, but if I didnt' finish in time, I wouldn't be able to go to work when the "vacation" was over. :( Then I'd have to do the rim replacement the next time off, cuz i have to swap them out on the existing motors, and there wouldn't likely be time to do that during the same "vacation".

So...while it might be the best solution...practical necessities mean it would probably be better to do it on a completely new trike, or at least after I've built a new one.

Also...as more or less noted in my reply to bdamari, unless the fat tires have the same kind of traction and puncture resistance (thickness), and the tubes for them are available really thick (or I can use the moped tubes), and with TR4 or TR6 valve stems...it would be problematic.
 
goatman said:
grin sells them
https://ebikes.ca/shop/electric-bicycle-parts/rims/rim20-fat.html

Thanks--that's probably as perfect as I will find in the short term. Just have to first make sure I can fit a 65mm wide rim in there (as it will make the tire wider, too). Not much clearance....

Unfortunately it is $66 to ship them to me, which puts the total pretty high, at about $150 for just two rims. Although looking around at some of the brands Balmorhea lists, they can be that kind of cost range (or more!) just for one or two rims, not including shipping.

But at least I have some idea what to look for now, which helps a lot, so thank you all for the info.


Still open to suggestions if anyone else has any, of course. :)
 
Balmorhea said:
I have one of those, do not mind to sell it.
It is almost new, only about 100Km made on it.
If some one interested just send me a message. I am located in Spain will send it in EU area.
 
Unfortunately it is $66 to ship them to me

Must be the package size, ordered spokes and couple of other things, think shipping was under $20. Was going to get a new rim but just the rim was $60+ shipping. Crazy shipping twice what the rim was.
 
Thank you all for the input. :)

Thanks to Chalo, the rim problem is solved for me ATM, with a couple of unused rims identical to what I have now, and is helping me find sources to buy the pedicab-type larger wheels and stuff to use on the new trike once that is designed and built. :)
 
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