Motorcycle rim?
- Thread starter ian.mich
- Start date
Motor cycle rims are sized differently to bicycle rims, a motor cycle rim is measured as the dia of where the tyre sits on the rim and a bicycle rim is measured as the outside dia of the tyre, as an example a 16" moped tyre will fit on a 20" bicycle rim. So if you where planning on putting 24" bicycle tyres on moped or motor cycle rims then you would need to do some research to find the bead dia of something like 19" rims to see if they would be suitable.
MattyCiii
100 kW
There's a lot that can go wrong with this type of mix and match. See my A-Line build thread. Here are some lessons I learned from my experience:
- The tire, inflated, won't likely be the specified width. This is because width varies with rim width. As a result my wheels barely fit my bike, I have maybe 3mm clearance on one side and 4mm on the other (need to center that wheel...)
- With spokes, thicker does not always mean better. Spokes work through tension. A thicker spoke needs more tension to do its job, and if your spoke is too thick you'll pull the flange right off the hub before you reach the appropriate tension. With this in mind:
- I bought 13ga spokes - a good middle between the moto rims and bicycle hub.
- I got these with oversized nipples... But even then, the nipple heads pass right through the moto rim spoke holes. Solution? I put washers on the nipples so now they don't fall through. This arrangement is holding up fine through wheel build, tensioning and truing - but I have not ridden the bike yet so I have no ruggedness test.
- I bought a tubeless tire, but as a spoked rim I decided not to try this setup as a tubeless wheel. That means I get the worst of both worlds:
- The tire was a SOB to mount. I had a motorcycle shop do it and they struggled.
- It's heavier than it has to be, with the tubeless construction and added weight of the tube.
- I get none of the advantages of tubeless
MattyCiii said:
Ok so you're saying:
get a motorcycle wheel and tire, run the tire tubeless if I can, get 13ga spokes and nipples, and what size are the washers and where do I put them on the nipple?
And I still havent had my question answered, where can I get a rim and i guess a tire too at this point?
Thanks so much for your help
MattyCiii
100 kW
ian.mich said:
Hmmm, let me clarify:
- I'm neither for or against the motorcycle rim/tire, that's your decision. But if you're convinced its right for you, the things I said are things to consider
- By the way I failed to mention that my moto wheel w/bike hub is terribly heavy.
- The point of my spokes/nipples discussion is that it's been hard to plan, to do, and has not (yet) proven its value - but only because my build is not finished.
That's the hard work, and it's so specific to your frame & your vision of the desired outcome that it's inherently a job you must do. I googled around for days to get the wheel/tire combo I bought, and even then there were revisions, risks and compromises.ian.mich said:
That info is more a metaphor for what to expect in your planning process. But here's more related info. I had to get spokes custom cut. I went to Holmes Hobbies. Notice "13ga large: 4.77 body 7.75mm head (special order)". I noticed #10 washers would fit my need: ~5.5mm ID is larger than nipple body and smaller than head: GOOD. It's OD is 12.7mm, which is larger than the ~10mm spoke holes in the rim: GOOD. Placement isn't tricky, just use the washers on the spoke nipple just like a washer used with a lag bolt. I used two washers because they're thin.ian.mich said:
Chalo
100 TW
ian.mich said:
There is no 24 inch motorcycle rim size. The largest diameter I am aware of is 21".
If you mean a motorcycle rim that is compatible with a 24 inch bicycle tire, that would be a 20" rim. Motorcycle wheels are categorized by the bead seat diameter, but bicycle wheels are designated by their nominal outer tire diameter. 24" BMX and MTB rims are 507mm at the bead seat, or 20".
I suggest that using a motorcycle rim on a bicycle is more complicated than you think, with no genuine advantages to speak of. Specialty bicycle equipment, e.g. downhill racing, dirt jumping, and freestyle rims and tires can be more than strong enough for what you have in mind, while being less costly, easier to service, and much lighter in weight than motorcycle rolling stock.
If you're having trouble with cheap or ordinary light-duty bicycle equipment, that's not a good justification for jumping directly to the wrong tool for the job. Just use good strong bicycle parts and have them assembled by a competent, experienced technician.
Chalo
Chalo
100 TW
ian.mich said:
26 inch MTB type tires only fit on one kind of rim, which is 559mm or 22" at the bead seat. You can get narrower or wider tires, but they all fit on a rim of the same diameter.
Chalo
Oh I was just wondering about the motorcycle rim as it seemed that was the best option due to strength, i guess its back to dual wall rim searching for me. also, ive been looking for hub motor spokes, i should get custom 13g spokes using the spoke calculator no?
John in CR
100 TW
My hubbies with 17" moto rims come out to be 23=24" OD wheels with the tires I have. An 18" rim may be a little better, because I think there's even more tire selection in an 18" for a smaller lighter lower profile tire.
My advice though would be to go to a 14" or 16" moto rim and get the size down closer to a 20-21" wheel. All hubmotors run better with smaller wheels. They are all geared too steeply with 24-26" OD wheels without adding many more pounds of motor. How do you think a fat guy like me has ebikes that all exceed 50mph and can climb mountains without burning up?
John
My advice though would be to go to a 14" or 16" moto rim and get the size down closer to a 20-21" wheel. All hubmotors run better with smaller wheels. They are all geared too steeply with 24-26" OD wheels without adding many more pounds of motor. How do you think a fat guy like me has ebikes that all exceed 50mph and can climb mountains without burning up?
John
rkosiorek
100 kW
if you are going for motorcycle tires on motorcycle rims, I'd say pass on the 16"moto rim. go for either a 14" or 17" moto rim. you have a lot more tires to choose from. 16's seem to be an unpopular size these days.
you can get some very heavy duty double wall bicycle rims for 26" tires, they'd be a lot lighter, cheaper and easier to fit than the moto rims.
rick
you can get some very heavy duty double wall bicycle rims for 26" tires, they'd be a lot lighter, cheaper and easier to fit than the moto rims.
rick
Chalo
100 TW
ian.mich said:
Here's a super strong, very inexpensive 26" bike rim that weighs a bit over 800g. My shop sells this rim for $36 retail. If you need more rim than this, you must weigh 500 pounds, or you're doing something terribly wrong with it. http://www.weinmanntek.com/Products/CHOPPER/DHL42.htm
The strength of the wheel is in the rim, not the spokes. I weigh over 325 lbs (I'm 6'8" tall) and I have fine results (no breakages) with 16ga and 17ga spokes in my own bikes-- they're just hard to build with because they twist up so much when being tightened. 14ga spokes are more than adequate for heavy-duty e-bikes, and they have associated advantages. They fit correctly in a bicycle rim without having to drill it out, and any bike shop has the right tools to service them. Top quality 14ga spokes are easy to get in any length, and reasonably priced, too-- how about $0.25 each for Belgian stainless spokes cut to order?
http://www.danscomp.com/products-PARTS-Spokes/435905/Sapim_Stainless_14G_Spoke.html
Mainly, though, 14ga spokes are most reliable because they are thin enough to stretch at tension levels a bicycle rim can withstand. That stretch is what keeps a spoke tight in the long run. Fat spokes-- 13ga and thicker-- tend to loosen chronically because when the rim is loaded, they go slack and the nipple can back off a bit. Repeat over and over, and all your spokes will be loose. Because the spokes are so thick, they can't stretch enough to remain taut through those loading cycles.
That's the reason butted spokes (those with thinner middles and thicker ends) are considered superior to straight gauge. It's not because they are lighter, even though they are. It's because they stretch more under the same tension than a straight gauge spoke with the same size elbow and thread. Paradoxically, the spoke that's thinner in the middle allows a wheel to carry larger loads reliably. Dan's Competition has 14/15ga butted Belgian stainless spokes for $0.40 each.
Chalo
Chalo
100 TW
rkosiorek said:
The advantage to 16", if there is one, is being able to use BMX and freestyle 20" tires instead of only heavy slow DOT tires.
Yep. The resulting wheel and tire combinations will be a lot faster than any motorcycle rolling stock, too, for any comparable treads.
Chalo
wesnewell
100 GW
I was looking for the DHL42 some time back and couldn't find them. Ended up buying 2 DH39 front wheels and taking the rim off one to use with my hub motor. 1000W yescomusa hub motor laced into it nice using 165mm 12g stainless spokes in a 1X pattern. Perfect for 1.95 and larger tires. FWIW, a 26" bike rim is 22.5" diameter.
Chalo
100 TW
wesnewell said:
Motorcycle rim sizes and ISO sizes for bicycle rims are based on Bead Seat Diameter (BSD). That's the size of the groove that the tire's bead wire sits in, which is a little bit smaller than the rim's measured size. Mountain bike rims (ISO 559) have a 559mm bead seat, which is 22 inches. 24" MTB is ISO 507, or 20 inches, and 29er is ISO 622, about 24.5 inches.
The ISO markings on bicycle tires put the width first, then the BSD. The width naming makes some assumptions about what width rim a certain size tire will be mounted on. Anyway, a 26 x 2.1" MTB tire is a 53-559 in ISO nomenclature. A 29 x 2.35" tire is a 60-622.
-dg
1 kW
Chalo said:
I second the DansComp recommendation and those spokes are really a bargain, most places are closer to a dollar each. Plus they were super nice to me when I screwed up my order. For hub motor building I was worried (probably unnecessarily) about the large holes in the flange so I used Pillar PSR TB 2018 which are 14/15 butted but 13 ga. at the elbows. Seem to be working fine, but regular ones would probably have been fine too.
Since this is a rim thread, let me ask for a recommendation for a stout but not ridiculous 26" for a hubmotor (BPM) rear to go on an early 90s Trek 950. I'm not huge, but pretty big and I tend to carry lots of stuff, say 350 lbs all up typically. I'm a big fan of utility cycling. I usually just use Sun CR-18s as they are cheap and decent enough, but I want something a bit wider for this bike. I suppose the Rhynolite is the default next width, but there may be better choices and I'd love to learn about them. Since the BPM has a fair amount of offset I was wondering if it is worthwhile to try use an offset rim (eg Velocity Synergy OC) to make the tension more symmetrical? Any suggestions?
Thanks.
Ch00paKabrA
10 kW
Being a dirtbiker, I have some spare wheels kicking around so I drilled out a hub to experiment with to accept 10 gauge spokes. I had a local bicycle shop lace it up and it works fine. The only issue is that the wheel and tire are fairly heavy coming in at about 12 pounds. The rim is a 21 inch excel on a cheap shimano hub that I got used.
Since it worked out well I did the same for the rear and I put some duro hf903 medians 90/90s-21 tires on the rims and the diameter is just shy of 27 inches.
After I get a rear hub motor for the bike I am going to grit my teeth and drill it out to accept the dirt bike spokes.
it you are buying new, then you might consider ProWheel rims as they are very good but are cheaper than Excell or Warp9. The enduro tires are also pretty good and are actually cheaper that some bicycle tires. I paid only about $53.00 for an actual motorcycle tire and I expect it to last a lot longer than a bicycle tire.
I was thinking of trying out an 18 inch rear dirt bike rim since they are fatter. The tire would be a bit taller so I estimate that the wheel would have a diameter of around 25 inches. I think this set up would be sweet for playing in the mud and snow with an actual dirtbike knobby tire on it.
Since it worked out well I did the same for the rear and I put some duro hf903 medians 90/90s-21 tires on the rims and the diameter is just shy of 27 inches.
After I get a rear hub motor for the bike I am going to grit my teeth and drill it out to accept the dirt bike spokes.
it you are buying new, then you might consider ProWheel rims as they are very good but are cheaper than Excell or Warp9. The enduro tires are also pretty good and are actually cheaper that some bicycle tires. I paid only about $53.00 for an actual motorcycle tire and I expect it to last a lot longer than a bicycle tire.
I was thinking of trying out an 18 inch rear dirt bike rim since they are fatter. The tire would be a bit taller so I estimate that the wheel would have a diameter of around 25 inches. I think this set up would be sweet for playing in the mud and snow with an actual dirtbike knobby tire on it.
Oh, this thread again, its been a while. stupid moto rims 
What i have done is below.
What i have done is below.ha nice. I too have settled the two DH39s from amazon. I actually unlaced both rims, relaced one in my motor with 12g holmes hobbies spokes in 1x. For the front the hub got replaced with a shimano disc hub, and reused the spokes. Tires are 2.1 schwalbe smart sam with a STOP FLATS liner, panaracer DH tube, and 2 rim strips (per wheel). The whole setup is going to last for long time and never pinch flat.wesnewell said:
johnrobholmes
10 MW
Motorcycle rims are great for high powered bikes, and smaller wheels get more geardown. While not everybody rides their ebike like a motorcycle, some people like the puncture resistance and extra rotational stability of the heavier rims and tires. I'm a light person at 150lbs and I can tear through MTB slicks like hookworms in a matter of 300 miles even on my 20mph bike. A Moped tire like a Shinko or Pirelli lasts 1500 or more at 30mph and offers a much better ride at those speeds.
Dans does offer a great deal on spokes. They do it by using 1/20th cost oriental nipples instead of supplying genuine Sapim nipples like the $1 per spoke companies such as myself. At 25 cents each I would be losing money on every spoke in machine wear and materials alone! We have considered getting a second machine just for 14ga to reduce prices on that type, but we won't be using cheap nipples to get there. Just a faster machine.
Dans does offer a great deal on spokes. They do it by using 1/20th cost oriental nipples instead of supplying genuine Sapim nipples like the $1 per spoke companies such as myself. At 25 cents each I would be losing money on every spoke in machine wear and materials alone! We have considered getting a second machine just for 14ga to reduce prices on that type, but we won't be using cheap nipples to get there. Just a faster machine.
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