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so i have a non drive pro class arm ,

finding a mate is .. well improbable ,

i found another non drive pro class arm
dose anyone see a reason why i cant weld crank pin and ride " other than the threads will be reversed" ?

back side pic of pro class drive arm would help.

Last edited by caligoose (2012-09-05 6:40am)

JacksonHole22 · 2012-09-05 7:07am

caligoose · 2012-09-05 7:10am

hmmm looks like i may be able to make it happen

now the question is should i .......

killer · 2012-09-05 7:13am

You'll nee 2 right hand pedals

caligoose · 2012-09-05 7:17am

sick , looks like ill have a decent set going for under 250$

whatupethan · 2012-09-05 7:58am

killer wrote:
You'll nee 2 right hand pedals

+1....... & one may spin

Last edited by whatupethan (2012-09-05 7:58am)

Coco · 2012-09-05 8:10am

whatupethan wrote:
killer wrote:
You'll nee 2 right hand pedals
+1....... & one may spin

Use Loctite, just not the red stuff.

mitchtram · 2012-09-05 8:17am

From Sheldon Browns Site:http://www.sheldonbrown.com/gloss_p.html

Direction
The right pedal has a normal thread, but the left pedal has a left (reverse) thread.

The reason for this is not obvious: The force from bearing friction would, in fact, tend to unscrew pedals threaded in this manner. It is not the bearing friction that makes pedals unscrew themselves, but a phenomenon called "precession".

You can demonstrate this to yourself by performing a simple experiment. Hold a pencil loosely in one fist, and move the end of it in a circle. You will see that the pencil, as it rubs against the inside of your fist, rotates in the opposite direction.

Ignorant people outside the bicycle industry sometimes make the astonishing discovery that the way it has been done for 100 years is "wrong." "Look at these fools, they go to the trouble of using a left thread on one pedal, then the bozos go and put the left thread on the wrong side! Shows that bicycle designers have no idea what they are doing..."

Another popular theory of armchair engineers is that the threads are done this way so that, if the pedal bearing locks up, the pedal will unscrew itself instead of breaking the rider's ankle.

The left-threaded left pedal was not the result of armchair theorizing, it was a solution to a real problem: people's left pedals kept unscrewing! I have read that this was invented by the Wright brothers, but I am not sure of this.

Note! The precession effect doesn't substitute for screwing your pedals in good and tight. It is very important to do so. The threads (like almost all threads on a bicycle) should be lubricated with grease, or at least with oil.

whatupethan · 2012-09-05 9:02am

^^^^ what he said....

caligoose · 2012-09-05 9:12am

i may remove and flip pedal boss to make it easy on myself

thell need chrome or powder anyway ...

looks like a go

Neil-Son · 2012-09-05 9:18am

caligoose wrote:
i may remove and flip pedal boss to make it easy on myself

thell need chrome or powder anyway ...

looks like a go

threads would still be the same direction ...try it on a bolt

Last edited by Neil-Son (2012-09-05 9:21am)

JacksonHole22 · 2012-09-05 9:21am

take some pics of the process...i'd be interested in seeing how this works.

caligoose · 2012-09-05 9:35am

will do !

i can accually have them made , even change the spindles to modern design .

but first set cost 600$ lol

tomandemmy · 2013-01-31 12:53pm

very cool !!! I wondered if you found another!

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pro class crank issue .....

pro class crank issue .....

#2 2012-09-05 7:07am

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#3 2012-09-05 7:10am

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#4 2012-09-05 7:13am

Re: pro class crank issue .....

#5 2012-09-05 7:17am

Re: pro class crank issue .....

#6 2012-09-05 7:58am

Re: pro class crank issue .....

killer wrote:

#7 2012-09-05 8:10am

Re: pro class crank issue .....

whatupethan wrote:

killer wrote:

#8 2012-09-05 8:17am

Re: pro class crank issue .....

#9 2012-09-05 9:02am

Re: pro class crank issue .....

#10 2012-09-05 9:12am

Re: pro class crank issue .....

#11 2012-09-05 9:18am

Re: pro class crank issue .....

caligoose wrote:

#12 2012-09-05 9:21am

Re: pro class crank issue .....

#13 2012-09-05 9:35am

Re: pro class crank issue .....

#14 2013-01-31 12:53pm

Re: pro class crank issue .....

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