19" Motorcycle Wheels vs 26" Bicycle Wheels (rim and tires)

[Rix]

As you are aware Amber, the industry metric size references are as follows for the 90/80-16. 90 is the width in MM, 80 is the percent of the height off the bead of the tires width, and the 16 is rim size. So we get about 3.5" of width and about 2.8" of side wall height on a standard 1.60x16" MC rim. Now if your rim is narrower, the tire maybe a little taller and less wide. Conversely if the rim is wider, the tire will be a little wider and slightly lower in sidewall height. On your 2.5-16 tire size refernce, we are missing the sidewall percentage height information as is the case with all tires that are size reference in inches instead of MM. That said, I know from personal experience with various trials and knobby tires from 2.5 to 2.75 wide also runs around 80% of its, except the Michelin M62 Gazelles series, which is more like 65-70%, we can figure out the difference. So my math tells me your 2.5-16 inch tire has a sidewall height of about 2" or so. Based on that, we should see a radius increase of about .8 for a total diameter increase of about 1.6". Thats my best educated guess Amber.

 

[amberwolf]

Thanks--that is helpful.

So it might be enough.

My rim is about 45mm, IIRC, so a few mm wider, perhaps, than the reference 1.6" MC rim. I don't recall if the 45 is between the beads or is the width at outerwalls; I'd have to check.


I could probably use the 80/80 version for a little less width and probably about the same height, then, but the 90/80 would hold a little more air, giving a little more cushion...and if I have to make new wheelwells anyway, I might as well do it for wider tires.

 

[Rix]

Thanks--that is helpful.

So it might be enough.

My rim is about 45mm, IIRC, so a few mm wider, perhaps, than the reference 1.6" MC rim. I don't recall if the 45 is between the beads or is the width at outerwalls; I'd have to check.


I could probably use the 80/80 version for a little less width and probably about the same height, then, but the 90/80 would hold a little more air, giving a little more cushion...and if I have to make new wheelwells anyway, I might as well do it for wider tires.

Thats going to be neat, post up a pic when you get it done.

 

[amberwolf]

Definitely...but it'll be a while. Hopefully not too long as the rigthside tire is pretty worn at this point (not nearly so much on the left side), and needs to be replaced soon. I'd much rather not buy another tire or set of them until changing to the new size...but I might have to.


The modifications will have to be some serious structural changes, something on the order of the stuff below, out of the SBC thread. Most likely the inboard half of that frame would simply replace some of the existing outboard frame, and the inboard axle mounts / dropouts (which would include the disc caliper mounts to be added) would end up somewhere around the "depth" the tire itself sits in right now, to prevent the overall trike width from increasing as much (so I can still get thru and around the aisles in the store I work at to get it into the breakroom).

https://www.endless-sphere.com/forums/viewtopic.php?f=2&t=67833&start=1000#p1555572

I'd love to widen the trike quite a bit, for better stability and better cargo capacity, but it would have to be parked outside in a parking space at that point, and be sitting in the Phoenix AZ heat all day long (bad for the battery), and also be vulnerable to mischief. :/

 

[synics]

Rix, I've literally perused every tire site for like a month, and when I say limited, I mean limited, LOL. That's why I was looking at thicker front tires as a back tire option because there are more 19" tires out there in that category. Everything in the rear tire category seems to be well over 4 inches.

https://endless-sphere.com/forums/viewtopic.php?f=3&t=53986

Check this old thread out amigo. Its Zombies' Greyborg build with 2.75-19 SR244 on Warp 9 2.15-19 rims, it gives you an idea what a 2.75 wide tire will look like on this wide of a rim. I actually talked to Zombies about his build and he loved the tire rim combo, said it felt super stable and really liked how it rolled. Unfortunately as you eluded to, if you don't go with a 2.75 wide tire, you got to go big then. I did a little research on the Conti Twinduro that you were looking at, it weighs 10 pounds. Thats lighter than other tires in the 100/90-19 catagory, but the 2.75-19 tires can be found all day long in the 5-6 pound weight range.

Rix do you still run the 241 on the front? I was thinking of getting that as my front tire. 21x2.75 Would that be a good choice? Are there better options? Money is no object...

 

[Rix]

Rix, I've literally perused every tire site for like a month, and when I say limited, I mean limited, LOL. That's why I was looking at thicker front tires as a back tire option because there are more 19" tires out there in that category. Everything in the rear tire category seems to be well over 4 inches.

https://endless-sphere.com/forums/viewtopic.php?f=3&t=53986

Check this old thread out amigo. Its Zombies' Greyborg build with 2.75-19 SR244 on Warp 9 2.15-19 rims, it gives you an idea what a 2.75 wide tire will look like on this wide of a rim. I actually talked to Zombies about his build and he loved the tire rim combo, said it felt super stable and really liked how it rolled. Unfortunately as you eluded to, if you don't go with a 2.75 wide tire, you got to go big then. I did a little research on the Conti Twinduro that you were looking at, it weighs 10 pounds. Thats lighter than other tires in the 100/90-19 catagory, but the 2.75-19 tires can be found all day long in the 5-6 pound weight range.

Rix do you still run the 241 on the front? I was thinking of getting that as my front tire. 21x2.75 Would that be a good choice? Are there better options? Money is no object...

I am. 2.75-19. When I was toying with the idea of going to a 21MC rim, I bought this tire and have it at the house. Its almost identical in size to a 27.5 MTB and is just over a full pound lighter than the SR241 in this size. https://www.bikebandit.com/tires-tubes/motorcycle-tires/vee-rubber-vrm-021-trials-tire/p/43168?b=3221312&CRTP=psc&gclid=EAIaIQobChMI4JPai7bj6QIV6B-tBh21iAKiEAQYASABEgJIjfD_BwE

 

[synics]

Interesting...do you think it works perform as well? Is the 241 too heavy for a front then?

 

[Rix]

Interesting...do you think it works perform as well? Is the 241 too heavy for a front then?

No I don't think it will hook up as well as the SR241, its just a lighter and narrower option.

 

[synics]

Rix my shinko 3.5x19 just got delivered. Holy crap this thing is bigger than I though it would be! Tall as my 26" mtb tires. I like the look of it though and how soft the rubber is. Now if I just had a DANG BIKE to mount it on. All my main stuff has been in U.S. Customs for like a month now and it's got me worried.

 

[Rix]

Rix my shinko 3.5x19 just got delivered. Holy crap this thing is bigger than I though it would be! Tall as my 26" mtb tires. I like the look of it though and how soft the rubber is. Now if I just had a DANG BIKE to mount it on. All my main stuff has been in U.S. Customs for like a month now and it's got me worried.

Don't worry about the customs issues, its the covid 19 procedures. during phase 2 which California and Nevada are in, we can only have 50% of the employees on site. Your stuff in customs is most likely waiting for someone to get to it and clear it. Aren't you glad you didn't order that 100/90-19 tire now? Its even bigger than your 3.50-19 SR241.

 

[synics]

Rix my shinko 3.5x19 just got delivered. Holy crap this thing is bigger than I though it would be! Tall as my 26" mtb tires. I like the look of it though and how soft the rubber is. Now if I just had a DANG BIKE to mount it on. All my main stuff has been in U.S. Customs for like a month now and it's got me worried.

Don't worry about the customs issues, its the covid 19 procedures. during phase 2 which California and Nevada are in, we can only have 50% of the employees on site. Your stuff in customs is most likely waiting for someone to get to it and clear it. Aren't you glad you didn't order that 100/90-19 tire now? Its even bigger than your 3.50-19 SR241.

Yeah I'm deff glad you talked some sense into me as far as the tire is concerned! LOL! I've changed a million bike tires in my life but never a moto tire this heavy, this should be interesting. I got all the tools to do it. Only thing that makes me wary is not messing up the phase wires going to the controller while I mess around with changing the wheel. Do you prefer dish soap, or windex when changing?

Regarding the shipping, yeah I hear you. It's frustrating because I paid for all of this stuff back in March, and here we are in June and I still don't have it, and it's just sitting in a warehouse somewhere.

Btw, do you think I'll need extra reinforcing for the dropouts given that this is a 273? I've seen so many posts and discussions about these things moving around in the frame and twisting it with even just the 205, I think I may have them machined to be better safe than sorry. If so is there any one design that works best?

 

[synics]

Look at this sucker, next to a 26x2.0 mtb tire.

 

[Rix]

Rix my shinko 3.5x19 just got delivered. Holy crap this thing is bigger than I though it would be! Tall as my 26" mtb tires. I like the look of it though and how soft the rubber is. Now if I just had a DANG BIKE to mount it on. All my main stuff has been in U.S. Customs for like a month now and it's got me worried.

Don't worry about the customs issues, its the covid 19 procedures. during phase 2 which California and Nevada are in, we can only have 50% of the employees on site. Your stuff in customs is most likely waiting for someone to get to it and clear it. Aren't you glad you didn't order that 100/90-19 tire now? Its even bigger than your 3.50-19 SR241.

Yeah I'm deff glad you talked some sense into me as far as the tire is concerned! LOL! I've changed a million bike tires in my life but never a moto tire this heavy, this should be interesting. I got all the tools to do it. Only thing that makes me wary is not messing up the phase wires going to the controller while I mess around with changing the wheel. Do you prefer dish soap, or windex when changing?

Regarding the shipping, yeah I hear you. It's frustrating because I paid for all of this stuff back in March, and here we are in June and I still don't have it, and it's just sitting in a warehouse somewhere.

Btw, do you think I'll need extra reinforcing for the dropouts given that this is a 273? I've seen so many posts and discussions about these things moving around in the frame and twisting it with even just the 205, I think I may have them machined to be better safe than sorry. If so is there any one design that works best?

I am a dish soap kind of guy, especially for seating the bead, don't be afraid to run the pressure up a little over max PSI rating if you need to to seat the bead. As far as drop outs go, over engineer the shit out of that, its better to be safe than have a structure failure.

 

[synics]

awesome. will do on both counts. ha. thanks man

 

[synics]

What kind of stand do you use to work on your bike? Obviously none of the regular bike tube type stands will work...

 

[Rix]

What kind of stand do you use to work on your bike? Obviously none of the regular bike tube type stands will work...

I will snap a pic of my stand and post it tomorrow. Nothing fancy, just a high lift hydraulic stand from harbor freight with a wooden deck bolted to it.

 

[HorizonLess]

New member here! Is there anyone here who has tried fitting 17” motorcycle tires on an mtb? And does it fit well if ever.

 

[Rix]

New member here! Is there anyone here who has tried fitting 17” motorcycle tires on an mtb? And does it fit well if ever.

In my avatar picture, I have a 1.40x17 rim on my Bomber running the shinko SR241 3.00-17 on the rear. I got some pics somewhere of various 17" MC tires on my ebikes, got to dig them up.

 

[synics]

So Rix, I've been working on my bike for the past two days, SO MUCH WORK and customization. It's like it never ends. Now I'm looking at the bike and it looks pretty sweet with the 19" back wheel and 21" front wheel. But if I mount this shinko 19x3.5 then it's going to take away that smaller wheel in the back look and raise the angle a bit. The shinko is at least an inch and a half taller than the 19" wheel that's on it now. I'm torn....

 

[HorizonLess]

New member here! Is there anyone here who has tried fitting 17” motorcycle tires on an mtb? And does it fit well if ever.

In my avatar picture, I have a 1.40x17 rim on my Bomber running the shinko SR241 3.00-17 on the rear. I got some pics somewhere of various 17" MC tires on my ebikes, got to dig them up.

That is an awesome looking bike you have there, it gives me good input on how the bike might look. Another question, how big does those wheel compare to 26er’s do they come close?

 

[Rix]

Here is a pic of Offroader's qulbix with the 17" rear and 26MTB up front. Should give you an idea.

 

[HorizonLess]

Here is a pic of Offroader's qulbix with the 17" rear and 26MTB up front. Should give you an idea.

Thanks you have been really helpful!

 

[Rix]

Here is a pic of Offroader's qulbix with the 17" rear and 26MTB up front. Should give you an idea.

Thanks you have been really helpful!

Anytime, post a pic here of your build when its up and running.

 

[synics]

Here is my progress so far. I am really torn on what to do about the tires. As you can see the shinko 19x3.5 241 is a BIG tire, and would raise the back up. The Shinko 21" is only a bit taller, so not much gained there. Think I should mount them or stick with the stock? Of course I haven't ridden it yet so I can't comment on the feel.

Also, here are the other things still needed to be done besides the tire drama:
1. Put in the battery, lol (it's sitting on the bench behind it)
2. Take off the derailleur and either go just go chain or add a smaller tensioner. Pretty sure that chain is gonna bounce around and smack the swingarm.
3. Fabricate the moto shock mounts and get that shock mounted.
4. Possibly put bearings in the swingarm pivot point and fabricate a spacer. I have to ride it and feel it out.
5. Find some small unobtrusive brake lights and wire them in.
6. Wire in the headlight that you see I have already mounted. The stock one that was there before had 3 wires, a red, back and yellow. I have NO IDEA what that yellow wire does, but it's connected to something else going to the controller. Think I need it?

That's is for now. Lemme know your thoughts!

 

[Rix]

Nice build going on Synics. Yah the wheels are a tough call, if you are only going to run the one speed set up, got with a Surly singulator or Paul Melvin chain tensioner, either one of those will be way better than the set up you have right now.