RadRover : how slim (Tires) can we go ?

Kyogiro

Member
I already replaced my rear tire with a Jumbo Jim 26x4 on my rear wheel. I have another one waiting for the front wheel.


I've been mostly riding my Rad Rhino (Rover) on pavement, I was wondering if anyone has tried to fit 2.25 wide tires.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
The 26x2.25's, in my mind, are way too narrow for the extra wide rims used with the 26x4" tires. The stock rims are usually about 80mm wide. Rims for 2.25 tires will be something closer to 30mm wide. What you CAN do is drop down to something like a 26x3" tire using the stock rims. I've done this using 26x3.0 Kenda Flames with decent results (though they may be hard to find), but there are others in that size range as well and my bet is they'll have similar results.
 

Kyogiro

Member
Thanks. I've seen users successfully switching to 3 inches tires.

I was wondering for 2.25" due to the larger choice of tires. Probably next year, I'll change for 3" tires after using my current Jumbo Jim ones (which should last longer than the Kenda stock ones according to reviews).
 

ExPatBrit

Active Member
I installed 3 inch street tires, quieter and faster and got slightly more battery range.

Three caveats, speedometer will read high, you can scrape the pedals when leaning over and cornering and the bike leans more on the kickstand. My original stand snapped off.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
You can have 27.5 (or 29'er) rims laced on to your existing hubs too. Getting ready to do that on my fatty (27.5 in my case). After giving them a fair try, I consider the 4" tires a mistake here. That's me though. Some love them!

Worth mentioning maybe, is that the balloon type tires like the Schwab Super Moto-X and Big Apple lines, do a REALLY nice job of providing both a nice ride AND low rolling resistance. Designed to be run from 40 to 20 psi, when run down in the 20-30psi range they provide a GREAT ride, and still manage to handle SOME sand well. Super Moto-X come in 2.4 and 2.8 widths..... just sayin.....
 
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m@Robertson

Well-Known Member
Region
USA
Assuming they are 80mm rims, you can go as far down as 2.35" with a Super Moto X. 2.5" with a Maxxis Hookworm is a very common thing to do for height-challenged riders looking to take the bike down as far as possible (typically petite women). Ride comfort is compromised though. Expect a hard ride like you would get with a road bike with 100 psi tires.

I did the Super Moto X tires on 80mm rims on a fast bike (not a Rad) and I also used an oversized tube to ensure the tire formed properly to the hook bead rims. Fitment was surprisingly good. But the ride absolutely sucked. At high speeds on the street (28+) it was just not worth the trouble.
 

Timpo

Well-Known Member
I already replaced my rear tire with a Jumbo Jim 26x4 on my rear wheel. I have another one waiting for the front wheel.


I've been mostly riding my Rad Rhino (Rover) on pavement, I was wondering if anyone has tried to fit 2.25 wide tires.
So you want 26 x 4 on rear but skinny tire on front?
 

Timpo

Well-Known Member
If you want skinny front tire, you should just get 700C or 29ER wheel.

Option 1: Get a 29ER fork so that you can install 29 inch wheel and tire. (or 700C)

Option 2: If you want to keep your current fork, you can get hub width adapter and axle adapter so that you can install Quick Release 700C or 29ER wheel. https://www.mtbtools.com/product/adapter-set-rear-hub-boost-application/

Option 3: Re-lace the rim by using 29 rim and fat bike (150mm I believe?) hub.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Re: hub width adapter, I'd approach something like that with a healthy dose of caution for a disk brake equipped e-bike. That rotor needs to line up on the caliper. Using a spacer of some sort is just about guaranteed to screw that alignment up. That's for starters. Then there's chain alignment issues something like that might get into. There's also the very real possibility of a need to change the amount of "dish" used to center the tire over the hub in a manner where all that lines up.

Not saying an adapter like that can't be made to work. Saying there's a good deal to keep in mind when considering one.
 

m@Robertson

Well-Known Member
Region
USA
From a purists' perspective I agree doing new wheels is the 'right' thing to do mechanically, but realistically you can get the desired result with just a tire.

And its reversible if you decide you want to go back.

I know the guy who did the yellow bike. Pic is from 2018 and he still has it like this. Me... I didn't last past 6 months and maybe 3000 miles. Both bikes use 80mm rims. The yellow one is 2.5" Hookworms. The orange one is 2.35" Schwalbe's. The sidewall/casing is actually straight up from the rim on both of them.

20170626_203443.jpg.c3358c20e7bee29529cc82e74eb47e20.jpg
img_20190907_175309[1].jpg
 

Timpo

Well-Known Member
From a purists' perspective I agree doing new wheels is the 'right' thing to do mechanically, but realistically you can get the desired result with just a tire.

And its reversible if you decide you want to go back.

I know the guy who did the yellow bike. Pic is from 2018 and he still has it like this. Me... I didn't last past 6 months and maybe 3000 miles. Both bikes use 80mm rims. The yellow one is 2.5" Hookworms. The orange one is 2.35" Schwalbe's. The sidewall/casing is actually straight up from the rim on both of them.

View attachment 95214View attachment 95216
That looks like the easiest solution. Just change the tire.

How's the speedometer though? Did you have to change it?
I know typically people just set their speedometer setting to 29 inch for 26 x 4.0 because of larger tire diameter.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
From a purists' perspective I agree doing new wheels is the 'right' thing to do mechanically, but realistically you can get the desired result with just a tire.

And its reversible if you decide you want to go back.

I know the guy who did the yellow bike. Pic is from 2018 and he still has it like this. Me... I didn't last past 6 months and maybe 3000 miles. Both bikes use 80mm rims. The yellow one is 2.5" Hookworms. The orange one is 2.35" Schwalbe's. The sidewall/casing is actually straight up from the rim on both of them.
On the bold, in your opinion, would the "desired results" include things like minimized rolling resistance and a great ride? Would love to know more about how rim vs. tire width play here.

I have 2 other bikes (both city bikes). 1 is a 26" and the second a 27.5, both equipped with 2.4" Schwalbe Super Moto-X tires front and rear, mounted on 30 and 32mm rims. Those bikes both work GREAT. They both ride better and pedal easier than the ex-fatty now running 26x3" Kenda Flame tires on 80mm rims. Those tires (the Flames) are about the same width across the tread as the rim is wide
(80mm= 3.14"- giving a great looking "square" appearance ). It seems to ride rough even down under 30psi. If I go much lower, like down into the high teens, I get into the dreaded self steering issue. My opinion above based on this experience.

Worth mentioning maybe, is the fatty is a Bafang Ultra Powered Rize. My current plan is to do a rim swap, and install a 2.8" Schwalbe Super Moto-X on the back and a 2.4" Super Moto-X on the front.
 

Timpo

Well-Known Member
Re: hub width adapter, I'd approach something like that with a healthy dose of caution for a disk brake equipped e-bike. That rotor needs to line up on the caliper. Using a spacer of some sort is just about guaranteed to screw that alignment up. That's for starters. Then there's chain alignment issues something like that might get into. There's also the very real possibility of a need to change the amount of "dish" used to center the tire over the hub in a manner where all that lines up.

Not saying an adapter like that can't be made to work. Saying there's a good deal to keep in mind when considering one.
yeah good point, I don't know about the integrity of adapter, but yea, that's just an option.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.

Timpo

Well-Known Member
Yes, they'll fit. The bike will roll with them installed. My question is more like will they perform as designed?
Well not likely, because 2.4- 2.6 tires are designed for 25mm to 40mm max.
So obviously RadRover's 80mm is too wide for optimal performance.

MTB_Tire_Rim_Compatibility.jpg
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Thanks for the charts Timpo. I rest my case....

Those charts pretty well match my experience. I like the second one better as it describes what you might expect to happen when you get too far away from "suggested".

There's still the point regarding will the skinny tires "work" on the fat rims, and clearly they will. Story there is about working as designed, and as the charts show, they do not. Point being, I suppose it depends on your interpretation of the word "work". So the questions that need to be answered - are you looking for something you can get by on, or something that will allow the tire to work as designed?
 
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Gordon71

Well-Known Member
Thanks. I've seen users successfully switching to 3 inches tires.

I was wondering for 2.25" due to the larger choice of tires. Probably next year, I'll change for 3" tires after using my current Jumbo Jim ones (which should last longer than the Kenda stock ones according to reviews).
What did you get for mileage on your Kendas? I've got about 2700 miles on my Rover (mostly pavement and groomed gravel trails) and there's still life left in them. I expect I'll replace them during the winter down time and will probably go with a street tire this time. Either 26X4 or 26X3 but will probably stick with the 4's as I'm too cheap to replace my tubes and Tuffy liners.
 

m@Robertson

Well-Known Member
Region
USA
That looks like the easiest solution. Just change the tire.

How's the speedometer though? Did you have to change it?
I know typically people just set their speedometer setting to 29 inch for 26 x 4.0 because of larger tire diameter.
Yes you do need to adjust your tire diameter in your display. Always necessary when fiddling with tire diameters. 29" is for big tires like a 4.5-4.8. 28" is what I am using right now with 4.0" tires on that orange bike. Arrived at via measuring.