Are 3.50-16 front motorbike tires roughly 100mm wide..?

[fireaza]

Hey guys! I'm looking for higher-end road tires to replace the knobbly 20x4.0 tires that came with my ebike. I've been looking for motorbike tires, since the only road-style bike I can find in 20x4.0 size are Supermoto X, which are a bit more on the expensive side and wouldn't be as hardy as a motorbike tire. Obviously, motorbike tires are heavier, but my bike gets a good week on a charge, so I'm not too worried about slightly reduced range.

At first, I had been looking for tires mark as "110/SOMETHING-16, since that seemed to be the figure that I saw online for what size motorbike is the equivalent of a 20x4.0 bike tire. However, I've measured the width of the tires that came with my bike, and they're actually 100mm wide, 110mm would scrape against my chain!

So instead, I've been looking at tires marked as "100/SOMETHING-16". I've been having trouble finding good choices in this size, just Dunlop K330A so far. But I've also seen tires marked in inches too, and according to THIS TIRE CONVERSION CHART, for a front, road tire (all the correctly-sized tires I've found are marked as "front" so I'm assuming I need to use the front measurement) "100/90 is 3.25/3.50".

However, not quite sure how to interpret this. By "100/90" do they mean "100mm wide, 90% ratio" or "100mm = 3.25" and "90mm = 3.50"? 100mm is 3.93 inches, but I'm assuming the difference is 'cuz motorbike tires are measured by the rim and not the tire. But either way, I'm not sure how a larger measurement in mm winds up as the smaller of the two measurements in inches, so that's clearly not right.

Does anyone know how to interpret this conversion? What 16 inch motorbike tires would be roughly 100mm wide in imperial measurements?

 

[Chalo]

By "100/90" do they mean "100mm wide, 90% ratio"

That means nominally 100mm wide, with the sidewall height being 90% of the width, or 90mm.

What 16 inch motorbike tires would be roughly 100mm wide in imperial measurements?

100/90-16, 100/80-16, 4.00-16

They'll weigh a depressing ton, and they'll be a bear to mount and dismount.

 

[Mongo]

Schwalbe's moped-ish 20x2.60 Pick-Up tire (65-406 ETRTO) is quite a bit narrower than your picks, but it's a pretty good roller and a tough tire. And it'll rim up with less fuss.

 

[neptronix]

..the huge weight and added rolling resistance will put a big strain on your ebike..
..i hope you have an excess of power available to you

 

[fireaza]

That means nominally 100mm wide, with the sidewall height being 90% of the width, or 90mm.



100/90-16, 100/80-16, 4.00-16

They'll weigh a depressing ton, and they'll be a bear to mount and dismount.

Thanks! Aren't tires measured according to the rim when measured in imperial units though? Hence why the conversion guide says "100/90 = 3.25/3.50"? I'm not finding any 16 inch tires marked as "4.00".

Schwalbe's moped-ish 20x2.60 Pick-Up tire (65-406 ETRTO) is quite a bit narrower than your picks, but it's a pretty good roller and a tough tire. And it'll rim up with less fuss.

Considering my wheels are sized for 4.00 wide tires, wouldn't 2.60 wide tires just, fall off..?

..the huge weight and added rolling resistance will put a big strain on your ebike..
..i hope you have an excess of power available to you

I've got a 1000W motor! If anything, heavier tires might make the bike less jumpy!