Comp 3 skinny vs Fat

[Topcat]

Probably a really silly question and no doubt asked at some point on here.......

How comes some pairs are sold one fat (20x2.125) and one skinny (20x1.75) and others are just 2 skinny's.  Also if you have a pair of 20x1.75 surely these wouldn't fit.   

Sorry showing my complete lack of BMX knowledge here! 

[CD17]

You can fit whatever size you want, a lot of bikes BITD came with a 1.75 on the back & a 2.125 on the front. I like the look of 1.75 tyres on both back & front 

[zed4130]

i usualy use skinny back fat front, but recently ive been using skinny both, im still not sure though 

[lazychubs]

yep what chris said
and the idea of a fat front
is to clear the way for the skinny rear tyre
in muddy conditions
not that im a bmx nerd or owt lol

[GREMLIN]

I was told when i bought my 1st bmx that the front tyre was wider so it has a bigger footprint. Making it grippier for turning in etc when racing. Where the rear only turns on the 1 axis, so can be slimmer. As if an 11 year old really cared  .
I prefer 1.75's front and rear  But do have fat/thin on 1 or 2 rides.     G.

[thesku11s]

sorry if im being obvious/patronising but it semed you were a little mixed up:

the 1.75 & 2.25 is relating to the width (fatness) of the tyre, the 20" obviously the diameter of the wheel.

Bmx tyres are all standard and you can fit any 20" on any 20" wheel.


in terms of the skinny/fat combo thing as gremlin said you dont need as much grip on the back.

thinner tyres are faster so you have them where you can. this is both because of less energy loss in a squidgy fat tyre and also less rotating resistance. they also weigh less.

It is often necessary to have a big un at the front ( at a sightly lower pressure ) to take some of the bumps.

[Topcat]

Thanks all

[stidds]

I must say that I only ever used 20 x 1.75 front and rear bitd, wouldn't have dreamed of racing with a 2.125 up front and I never had problems with grip.

[Trev]

i go with a chunky 2.25 front and a skinny rear...

[MartyC]

the 1.75 & 2.25 is relating to the width (fatness) of the tyre, the 20" obviously the diameter of the wheel.

Bmx tyres are all standard and you can fit any 20" on any 20" wheel.

Close, but a 20 x 1 1/8 or 1 3/8 tyre will not fit a 20 x 1.5 or 1.75 rim.  Don't mean to be patronising either