… are they all the same ? Bar Mopeds etc ! ie 700c etc ??

I know nothing about motorcycles !

ish. Mostly 17″ Diameter on modern bikes

Adventure bikes will vary 18-21″

Sports bikes are 17″ front an rear. Dirt bikes 21″ front 18″ rear ( mainly) Cruisers often have a large front wheel and small rear. Faux dirt bikes 19″ front, 17″ rear

so no – sizes vary

At the extreme ends of the spectrum Honda xl 500 with a 23″ front wheel and
Moto guzzi lemans mk4? with a 16″ front wheel

The Yak has a few motorbikes. TJ is along the right track. Most street bikes will have 17 inch wheels with a big selection of tyres, some have a 19 inch front. The Yak has an “adventure bike,” whatever that means, and a couple of dirt bikes that both have 21 front and 18 rear.

Sports bikes 17 inch (some older had an 18 rear, which limited your tyre choice to Michelin “Hyside” Sports or Japanese-no-grip-ever-lasts….go ask me how I know, I’m not bitter……..)

Race bike dabbled with 16.5 but I’m not sure wether that’s petered out now

oh and the earlier Fireblades had a 16 inch front which led to some interesting handling foibles.

I think even the first Hornet had a 16?

Course, just like cars, you get different widths of rim, different heights of tyre… My SV came with a 120/60 but I switched it (like everyone else) to a 120/70 because that’s what most sportsbikes use so they’re cheaper and more available, frinstance.

Op asked about circumference. Everyone gave diameter. I assume you did actually mean diameter op?

Funnily enough I’ve been trying to measure the circumference of my motorcycle front wheel today as I’ve fitted a digital speedo and need it for calibration.

I put a tape measure on the floor with the valve at the bottom, rolled it forward until it was in the same position.

I made it about 1850mm (Gsx750 inazuma)

I ran over my tape measure and it’s knackered now. Plus, the setting seemingly didn’t work as it had me down for 110mph when I was doing about 45 😂

my SR250 has a 16″ rear and a 18″ front, but my Triumph Street scrambler has a 17″ rear and a 19″ front

Kayak: just enter your radius in here…

Ooh thanks. I knew it were something to do wi pies. 👍

1850mm sounds about right for a typical 17″ front wheel. How many magnets is the speedo reading from?

kayak23

I ran over my tape measure

Pro tip- mark the floor/ground, then measure it after doing the bike rolling

1850mm sounds about right for a typical 17″ front wheel. How many magnets is the speedo reading from?

This is the thing. None. I have a widget that converts the analogue cable signal into digital. I think that’s where it’s going wrong as the manual only mentions magnets in setting up, . Nothing about using a converter.

Pro tip- mark the floor/ground, then measure it after doing the bike rolling

Now why didn’t I think of that! 😄