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Technical & Reference Section => Tech and Restoration => Topic started by: Frosty on December 12, 2005, 02:12 PM

Title: I know this has been asked before but
Post by: Frosty on December 12, 2005, 02:12 PM
something that I had not ever given any thought to caused me a problem at the weekend.

I was trying to build up a pair of mini wheels using Araya 1 3/8th rims and Suzue large flange hubs using 14x7 7/16 double butted spokes, same size I used on the laserlite wheels I had built. But they are way too short, I hadn't appreciated that the 1 3/8th rims are way bigger in internal diameter than the usual 20x1.75 Araya 7x rims!!

I guess the 20 refers to the diameter to the outside of the tyre that is being run and not the internal of the wheel!!

Please can some advise (ball park) what length spokes are needed for such a build?

Thanks

Paul
Title: Re: I know this has been asked before but
Post by: lazychubs on December 12, 2005, 05:52 PM
ive just built some sew up rims with high flange hubs all i did was nick the spokes out of some old chrome wheels i had
fink they was 143 mm
Title: Re: I know this has been asked before but
Post by: aditup2004 on December 12, 2005, 06:27 PM
Sounds far too short that. I think you will be looking at about 180mm depending on the spoke pattern. Try this;
http://www.wheelpro.co.uk/spokecalc/

 ;) Ad
Title: Re: I know this has been asked before but
Post by: steve on December 13, 2005, 12:41 AM
the 20 by 1.1/8th wheels are actually a 451mm rim

-the 20 by 1.75 is actually 406mm
-so

451 - minus 406
=45mm
-halved = 22.5mm

-so add 22.5 mm to the spoke length you have already
 :D

sew ups are 406mm- i think
Title: Re: I know this has been asked before but
Post by: Frosty on December 13, 2005, 05:07 PM
Steve,

Thanks, do you know what the 1 3/8th rims size is?

That's long spokes for a 3 or 4 cross build :o

Regards

Paul
Title: Re: I know this has been asked before but
Post by: steve on December 13, 2005, 06:03 PM
flange size?
spoke is 210mm to rim
(http://www.radbmx.co.uk/archive/albums/v222/pantswagen/IM000041.jpg)
Title: Re: I know this has been asked before but
Post by: aditup2004 on December 13, 2005, 06:41 PM
410mm? :santa_shocked: What you building, a penny farting :santa_grin:
Use the spoke calculator, its easier than you think. :idiot2: :santa_grin: ;D ;)
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