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Technical & Reference Section => Tech and Restoration => Topic started by: Andy68 on November 19, 2011, 09:27 PM

Title: Wheel size, I never realised.......
Post by: Andy68 on November 19, 2011, 09:27 PM
That 20'' rims aren't 20'' diameter. Only took me 30 years to learn that!!   :crazy2:  My missus has just been lookin' at the Junior build and asked why the wheels are bigger than on the others. Told her to stop being stupid its just an illusion cos of the shallow tyre sidewalls. Out came the tape measure, feck me the diameter is about 16 1/2 '' on the 7X's and 18'' on the Ukai skinnies.

So wots that all about or am I just been mega stupid?? 20'' = Rollin' width with tyre fitted I guess.   :-[    :idiot2:
Title: Re: Wheel size, I never realised.......
Post by: Gnarlyscoots on November 19, 2011, 09:31 PM
20'' = Rollin' width with tyre fitted I guess.   :-[    :idiot2:

Spot on dude  :daumenhoch:
Title: Re: Wheel size, I never realised.......
Post by: xGoose on November 21, 2011, 08:38 AM
Yeh be careful with that, I found out the hard way.

1.50 / 1.75 (standard typical BMX pro size) rims are approx 406mm and 1-1/8 / 1-3/8 (mini / junior) rims are approx 451mm. (I think this measurement corresponds to the tire bead.)

So frame sizes and especially tire, tube and brake sizes are different. You can be lucky and get away with frame size (ie fit a 1-3/8 wheel to a standard 20" frame), but you'd need to play around a bit to get the brakes to line up. If you're talking about new school race then LDC brakes have enough adjustment to cover both sizes.


Title: Re: Wheel size, I never realised.......
Post by: BENDYCAT ELEVENTEEN on November 21, 2011, 10:06 AM
your wife is sharp - watch her  :shocked:  she will start noticing parts you buy in and when you say "i didn't get any parts last week ?" she will know you are lying and then yer for the chop

hide parts
get then sent to another address
say you are just getting it sent to your for your mate - walk it out the house and then bring it back after dark

just watch her mate  :shocked:
Title: Re: Wheel size, I never realised.......
Post by: wildon on November 21, 2011, 10:17 AM
I just had some 16" wheels delivered and they are tiny .. they are actually only 12"  :shocked:
Title: Re: Wheel size, I never realised.......
Post by: Andy68 on November 21, 2011, 01:07 PM
your wife is sharp - watch her  :shocked:  she will start noticing parts you buy in and when you say "i didn't get any parts last week ?" she will know you are lying and then yer for the chop

hide parts
get then sent to another address
say you are just getting it sent to your for your mate - walk it out the house and then bring it back after dark

just watch her mate  :shocked:

 :LolLolLolLol:   All avenues covered fella.  :daumenhoch: 
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