Fat tires for class 3+ urban utility bikes?

I've been researching fat bikes lately, but all of the writing about them has been in the context of mountain biking and snow riding. I am more interested in them for Class 3 urban riding, but have not been able to find much info about this type of bike. My current bike was a busted eZee Sprint that I've been building up into an urban cruiser. Right now it has a Wald 3133 front basket and a Companion rear seat with a Wald 583 folding basket attached to the rails. I also have an Arkel pannier backpack and a milk crate I can secure to the seat (or I can just tie down heavy items directly to the seat). All together, it can carry a significant amount of cargo for a non-cargo bike, and I'm planning to add capability for 28 MPH bursts of speed with a Phaserunner. The problem is that I would really hate to hit a pothole at 28+ MPH on 1.75" wide tires while loaded down, and I can see this type of bike working a lot better with 3.8" tires. Other than lower battery efficiency and slower acceleration (which is just an excuse for moar power), I can't see any significant downsides.

If there's one thing I've learned in my research and experience with e-bikes so far, it's that if a seemingly brilliant idea doesn't already exist, there are usually good reasons why not. The only fat tire urban or cargo bike that springs to mind is the Surly Big Fat Dummy, and they always market it as a cargo bike for trails, and always recommend the Big Dummy instead for urban riding. So I put the question to E-S: Why are companies not selling fat tire e-bikes for high-speed urban utility and cargo, and why would it be a bad idea for me to build up such a bike?

Fat bike tires are thin as baby bum skin and twice the cost. They are for soft or loose terrain, where their size advantage is a compensation for their downsides.

In the winter, studded fat bike tires are not bad on snowy streets. It is the only situation where I would find them acceptable for urban use.

On performance ebikes, the best tires are 3.0

Yes, you might want to take a look at the plus tire bikes or boost spacing bikes. We have a full suspension plus bike we mostly ride on the streets. We get up to about 40-45mph going down some hills and it is pretty stable at speed. I would not want to hit a pothole at 45mph but I think we would be ok at 20-25mph. I carry my dog se we are pushing quite a bit of weight, maybe 280 lbs total including the bike. There are a couple decent street treaded tires in the plus sizes too. Whatever you buy if you are going to be riding over 25mph you may want to look into some better brakes. The standard hydraulics don't seem to have much bite over 20mph or so, it seems 4 piston and possibly a larger diameter rotor may be the way to go.

First, how wide are the stays and fork on your bike?

If they aren't wide enough, you can't fit fat tires in there, so you'd have to build a new bike to do it.


Second, as pointed out, typical "fat tires" are very thin; the ones I've seen personally are all thinner than even regular lightweight road tires. Those I know here that are using them have to keep refilling them with Slime or similar, because they get holes with all sorts of road debris, thorns, etc., and leak all the time, requiring re-airing between rides (or even during rides).


If you want tougher tires that are wider, there are bicycle-class tires (Chalo posted a number of good options in my SB Cruiser thread and elsewhere), but for myself I went with 16" moped/motorcycle tires by Shinko, 2.5" wide (there are wider versions) SR714s, on 20" bicycle rims, for the rear of SB Cruiser. They have lasted way longer than any bike tire I tried on there before, with no puncture failures. And they don't cost any more than a bicycle tire. But of course they are a lot heavier, as that toughness comes from thickness.

That option is for 20" wheels, but there are options for larger diameter wheels; I think 19" motorcycle tires fit 26" bicycle rims (at least some--there is a whole thread dedicated to that around here with lots and lots of info).

Someone put maxxis hookworms on a fatbike over on endless sphere so that has me wondering if you can just use Plus bikes tires on a fat bike. Use studded fatbike tires in winter and hookworms all the other times.

Putting a 2.5 tire on a 4’’ rim is not the best idea. But, putting another wheel with a smaller rim and tire is OK.

Yet, you can build with a reasonably wide rim, 47 to 67mm, and use 3.0 tires all year long. Ex. Innova Street Hog in the summer and Duro Wildlife Leopard in the winter. And, if you want to try, a 4.0 fat bike tire can be mounted on a 67mm rim. I prefer 3.0 on the street.

I have heard good things about the super moto-x tire in 27.5 x 2.8. They weigh over 2lbs each and are rated for use on 50kph ebikes, and they have a nice street tread. They have extra sidewall and puncture protection too, I am waiting for my rear tire to wear out and then I would like to try one. I am sure they are not as durable as moped tires but they sound fairly capable for a street e-bike.

I have heard some good things about the Duro Beach Bum 26" x 3" tire mounted on 100mm rims, at least good for cheap tires. The company endorses their use on up to 100mm rims. I hear they really reduce the drag from fat tires for street riding.

Pic of 3" beach bums on 100mm fat rim:

I would not ride hard and fast on tires that are mounted on rims that are wider that them.

Even at equal width with the rim, a tire has poor cornering action. I ride the Beach Bum on 67mm rims max, 57mm for optimal cornering speed. The Beach Bum has soft gum and pretty thick sole, that is a plus. It is a very good tire for clean pavement, and can take hits. My braking distance on Beach Bums inflated 22 PSI on 57mm rims is very good, and cornering can be very aggressive. Overall better than Street Hog, but the Street Hog does better on wet. The Street Hog is available 4.0, and even 6.0 but hard to find in some sizes.

I wish they made them for 27.5 rims, I would love to try them The most interesting I have been able to find for my rims looks like the supermoto-x.

I am afraid the Super Moto will be your only good choice for a while. 27.5 is not yet a priority for street tire makers. But, some DH racing tires after they are worn out, can be a very good street tire for some time. That is because soft gum is common in DH, and tough casings too.

It’s been a while that I ride 24’’ wheels on the street, and 26’’ in the mountain. The main reason is tire choices and availability. DH tires are now in a good selection for 27.5, but rims and tires are so common in 26...

You would probably laugh but before I went looking at bikes I shopped for tires. I had to make sure there was a supermoto type motorcycle tire available for the bike before I bought one There are so few tires that I like - hookworms, smx, duro bb, and the somewhat expensive vee speedster. That was all I found after an entire day of researching tires!

They will come. I mean, 27.5 had been adopted by bike manufacturers, the most popular tires will follow. But, there is some delay, especially to fill small markets. Street tires in 27.5 won't be common for a while. If you have disc brakes, you can swap wheel sizes at will. Used 26 DH wheels can be found cheap, so you can mount a spare with a tire that you like.

I'm riding my Mxus 3000w Fatbike in Thailand on local roads, and hard pack gravel and dirt trails and regularly will cruise at 50kph very comfortably, with a lovely, smooth handling bike with no problems.
My bike has 26" x 100mm rear rim, and 80mm wide front rim and now fitted with Chaoyang Sandstorm tyres, with wire beads and 30TPI, so thick carcass. They have good grip, very quiet, track straight and no punctures so far.
Before fitting these, I ran the bike for 3800kms on factory fitted Chaoyang Big Daddy 26x4.9 tyres and they were also fine, although noisy and even though they were 120tpi and quite thin carcass, I only experienced 1 rear puncture in all that usage!
I would highly recommend the Chyoyang Sandstorm tyres with 30 TPI Carcass. I bought my tyres from Ridewill in Italy, who offer great prices, have good stock and ship worldwide.
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Super Moto-X tires sound like a great upgrade, and my quick visual inspection shows that there should be plenty of room in the frame and fork for bigger tires. I've already decided that this bike project is never going to be finished, so why not add new rims with tires and a total motor and hub re-lace to the docket? That will be in addition to a Phaserunner, torque-sensing BB, TDCM rear hub for 2WD, and more things that I'm sure will strike my fancy in the future!

If you are riding on decent roads, IMO you can't beat a Schwalbe Super Moto-X in size 27.5x2.8". They come in other diameters and widths but the 2.8 is the widest option.

My second and third choice would be a Maxxis Hookworm or a smaller Schwalbe Super Moto-X.

I have a Duro Beach Bum 26x3.00 on the way but haven't tried it yet so I can't say ya or nay.

Agree with Mad Rhino...fat tires in general are thin and would not be the best choice. If they made them thick enough to be durable, they would be very heavy.

Johne-bike mentioned a good option. I have a set of 26x4.00 Chaoyang tires that have worked great on the road. They are super heavy and not your typical fat tire. Only fat tires I have ever touched that I would consider for pavement. BUT the 4.00 tires won't fit in anything but a fat bike frame, even if you mount them on a 52mm internal width rim...I tried :lol: .

I would really like to try a Chaoyang Sand Storm in size 26x3.00...they list it on their web site but I can not find it anywhere.

What the heck are the classes for ebikes, who cares, just ride. Not like the fuzz is going to know the difference.

It is not about what is "legal" it is about not having a tire failure when you are going around a corner and leaving a lot of your skin on the pavement...that is not a lot of "fun".

I had a tire explode at 35 mph...luckily I was going in a straight line and could come to a stop without crashing. Now I only use tires that are ECE-R75 certified for 50 Kph (31 mph) and although I exceed that speed, I have never had a problem with any of them .

On the Chaoyang tire, what's this interior portion that's shown in the picture?



is that just a rim with no spokes that will not ship with the tire?

owhite said:

On the Chaoyang tire, what's this interior portion that's shown in the picture?

is that just a rim with no spokes that will not ship with the tire?

Click to expand...

It is the rim that you see in this pic. It does have rectangular holes through which you see the rim band.

Bullfrog said:

It is not about what is "legal" it is about not having a tire failure when you are going around a corner and leaving a lot of your skin on the pavement...that is not a lot of "fun".

I had a tire explode at 35 mph...luckily I was going in a straight line and could come to a stop without crashing. Now I only use tires that are ECE-R75 certified for 50 Kph (31 mph) and although I exceed that speed, I have never had a problem with any of them .

Click to expand...

Then maybe motorcycle tires would suffice but like you said there is ECE-R75 and more and more certificates are out there, I seen ebike brake pads, ebike inner tubes, theres probably ebike rims. Hope you dont do 50mph+ on that, bicycle components are not meant for those kinds of speeds even though people have been getting away with it.

Based on my experience...if you are running all "bicycle" components i.e. frame, rims, tires, brakes, etc., about 30 mph is as fast as you can "safely" go without worrying about exceeding the capability of the components. Of course that assumes you are running "good" bicycle components.

Can you go faster than 30 mph on a "bicycle"...well sure but not something I would consider safe or smart.

As always "It Depends". I am building a bicycle that should do about 45-50 mph and I am using all bicycle components BUT I will only be running it in a straight line and I'll have plenty of room to slow down AND there won't be any four wheeled vehicles trying to kill me :lol: . I'll be running it on a runway in Blytheville, AR with the East Coast Timing Association to set a speed record for a supplied voltage of 52.8v. When I get home I'll go back to my "bicycle" that has a top speed of a little less than 30 mph for riding on roads where I turn left/right and have to avoid four wheeled vehicles :wink: .

You CAN go over 30 mph relatively safely on two wheels. Just upgrade your equipment appropriately...both your vehicle and your personal safety gear .