9/16"-20tpi Crankarm Footpegs?

fatty

10 kW
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My next build has a 24T drive chainring and 50T driven sprocket for a gain ratio of 1.0, and thus will not be pedaled with force.
I'd like to save weight and use light motorbike-style footpegs rather than full pedals.

Most similar threads relate to footpegs directly onto/into the bottom bracket.

What would you do for light footpegs for 9/16"-20tpi crankarms?
Long 9/16"-20tpi bolts inside knurled 1-5/8" PVC tubes? May not be any cheaper or lighter than pedals.
Use bare replacement spindles with grip tape? Aliexpress has "titanium" for under $18 shipped/pair. Would need a large flat washer on the end to decrease injury risk in an accident.
 
Just cut off the pedal itself. Find a pedal with the correct contours of the middle and cut off all the rest.

As an example from random search engine pic. Keep the red middle part with its wider black bits and cut out the rest. Then you'd need to add texture so your shoe doesnt always slip off it. But the key is to find the right pedal to do your angle grinder handy work on :thumb:


1.jpeg
 
Of course: rectangular tube TIG-welded directly to the crankarms. Square tube would give good platforms at 12 and 6, rectangular only at 3 and 9 o'clock positions. Are 12 and 6 used when cornering in such an application?
 
markz said:
Just cut off the pedal itself.

Yes, I thought about this, but I expect that swiveling pedals give a less-stable platform compared to fixed footpegs -- even with both on crankarms.
This instability due to swiveling would be exacerbated if the platforms are shortened longitudinally.
 
I dont see why you'd want to bother. What bike are you wanting crankarm footpegs? Enduro? MTB? DH? XC? Custom? Cruiser?

I see I did not post what I had typed out before I left for Bass Pro today. I basically said that yeah you can do round, triangle or square tubing, buy your aluminum metal but weld on a L or T to stiffen the custom aluminum peg, exact same metal welded together for extra strength and all the stress is on the peg joint. Then weld the the new metal to the arm with its dis-similar aluminum, and bracket or gussets. If you do zero pedaling that it shouldnt be an issue but I understand you want some movement. The top part of the L is the peg, the bottom part of the L is welded to the crank arm. The bottom part of the T is the peg, and the top part of the T is welded to the crank arm. And gussets. No moving parts, no rolling action of bearing so depends on how much you want to pedal. Otherwise the metal is moving under your sole creating heat, if you pedal enough. Then again your still dealing with slippage, I keep thinking of your idea and LineX or bed liner keeps coming to mind :lol:

As for the 3 and 9 or 12 and 6, remember you can also do 3 and 3 or 12 and 12, have both pedals pointing same way. Its an option but would feel totally wonky. I did it for giggles one time, very odd feel.

I would try my original method with some old pedals and see how it goes. You can always weld metal to the pedal peg and see how it feels when riding. You want more of a platform weld on some flat plate, or flat plate 2 sides, or 3 sides or 4 sides to box it in. Doubt you'd find square tubing to fit existing pedal.
 
So if doing an L, would mean you want the peg to be at the end of the crank arm.
If you have some room weld up a T.
Remember there are different lengths of crank arms.

Some people just get rid of the BB and weld up steel or alum right to BB. But thats not what you want, which is why I said you still want movement otherwise why bother playing around with the idea, just weld on pegs to the frame or whatever.
 
markz said:
As for the 3 and 9 or 12 and 6, remember you can also do 3 and 3 or 12 and 12, have both pedals pointing same way. Its an option but would feel totally wonky. I did it for giggles one time, very odd feel.

Yep -- thought about that too, but matching crankarm orientation would always come to rest at 6 and 6 -- ideal to get low CoG, and would swing back on acceleration and forward on braking -- good to brace against.
But couldn't even pretend to be pedaled, and high risk of "pedal" strike even with bottom bracket rise of 7mm and 162mm crankarms.
4:30 & 7:30 may be a good compromise, but one foot would always have to lead -- may get uncomfortable?
 
Received 1" x 1" Perforated Square Tubing, 16gauge 6061 T6 Aluminum. 12" weighs 100g, plastic endcaps weigh maybe 6g, so two 5" pegs with caps would weigh 89g, not counting heatshrink and/or griptape. The strength:weight:cost ratio is very attractive -- I think I'll try it.
 
Why limit yourself? In off-road motorcycling pegs that pivot are desirable because they offer good support at all angles.
 
TDB said:
Why limit yourself? In off-road motorcycling pegs that pivot are desirable because they offer good support at all angles.
Moto footpegs only pivot upward, and only then to prevent the footpeg from levering the tire off the ground. I've never seen moto footpegs that pivot on an additional axis.

In any case, the pegs are going on crankarms, the rotation of which would put pivoting footpegs upside-down, and pivoting in the wrong direction: downward.
 
That's not true...

https://pivotpegz.com.au/pages/pivoting-action

Saying stick to MTB pedals.
 
TDB said:
That's not true...

https://pivotpegz.com.au/pages/pivoting-action

Saying stick to MTB pedals.

Ah, interesting find. "Unique & patented", as they say though.
Still wouldn't work on rotating cranks.

I'm definitely not committed to the square tube experiment. I have no idea how it will compare to pedals.
 
fatty said:
TDB said:
That's not true...

https://pivotpegz.com.au/pages/pivoting-action

Saying stick to MTB pedals.

Ah, interesting find. "Unique & patented", as they say though.
Still wouldn't work on rotating cranks.

I'm definitely not committed to the square tube experiment. I have no idea how it will compare to pedals.

You're still missing my point... or just being argumentative.

MTB pedals do the full 360deg and offer support.
 
TDB said:
You're still missing my point... or just being argumentative.

MTB pedals do the full 360deg and offer support.

I'm definitely still missing your point. Are you suggesting pedals instead of pegs? If so, what was the point of posting one-off pivoting pegs that won't work on crank arms?

I don't disagree about pedals, but I haven't found any references to pegs on crank arms to rule them out. That would be most helpful.
 
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