Well done on getting the holes straight with a hand drill. That is one task I have a great deal of difficulty with. I was thinking that maybe drilling and tapping for 1/2" pedals in this situation might be advisable, but that's only because I have both 1/2 and 9/16 pedal tap sets.
I've been trying to decide whether to buy new crank arms for my bike.. but because of your video I'm going to do this! do you think I should?? I've recently gone from a well rounded CCM to a Turner Downhill bike... and I'm sooo sore after pedaling it around flat trails. My knees come up so high! Butt and hip flexors just beaten!! Should I get used to it?? Do I need the leverage? (I will also need a smaller crank sprocket if I go down to a 155) My frame is a medium, and I'm 6' tall. I can't really get the seat high enough without it being way too far back. the bike isn't the right size for me. I think I can weld a saddle onto a spare clamp in a much farther forward position, then I think the bike will feel nicer. And I might be able to get the height I need for the 175 arms to feel better. Fascinating!! Left Side: Counter Clockwise motion of the crank makes the relative motion of the pedal Clockwise, intuitively you might think (I did) the RH threads would be on the left..???? EDIT: I have researched, and it is due to mechanical procession. So indeed, that is why LH threads are on the left side.
Hola ,se que es un comentario viejo,pero yo también pensé que los sentidos de rosca en mis pedales no tienen sentido ,y no encontré explicación! Si pudieras explicar lo de "precesión mecánica " o compartir algún enlace al respecto te lo agradecería mucho. Saludos y gracias.
I wanna do it but I dont know which length to choose. I was ridin 170, then switch to cheapest 150 and its much better but momentum is reduced by third. Im thinking about making 156, 157 or 158 but its just guessin. Maybe this could be calculated?
I think as long as the crank is used for it's intended purpose (50lb child riding in the 150mm length) I feel it will be more than strong enough. Trek actually specs most of their 20" and 24" mountain bikes with a dual position setup like this. I definitely wouldn't feel comfortable with a larger rider or adult riding this setup in an aggressive manner, but it's my young daughters bike. She was on a 20" bike that she out grew, and this is a small 13" frame 26" wheel Trek mountain bike. She fits the bike ok, but the cranks were just a little long for her currently. If the crank mod works out, I'll probably get another crank in the appropriate length that I can set up in a 1x system (the crank I modified has a stamped non removable 3 piece chainring ). Thanks for your comment and question!
Well done on getting the holes straight with a hand drill. That is one task I have a great deal of difficulty with.
I was thinking that maybe drilling and tapping for 1/2" pedals in this situation might be advisable, but that's only because I have both 1/2 and 9/16 pedal tap sets.
Thanks! Yeah, 1/2" would definitely be stronger but we only had 9/16" taps at the shop.
WOW Very clever!
Park recommend a 33/64" drill bit.
Just what I need. Thank you!
I've been trying to decide whether to buy new crank arms for my bike.. but because of your video I'm going to do this!
do you think I should??
I've recently gone from a well rounded CCM to a Turner Downhill bike... and I'm sooo sore after pedaling it around flat trails. My knees come up so high! Butt and hip flexors just beaten!! Should I get used to it?? Do I need the leverage? (I will also need a smaller crank sprocket if I go down to a 155) My frame is a medium, and I'm 6' tall. I can't really get the seat high enough without it being way too far back. the bike isn't the right size for me. I think I can weld a saddle onto a spare clamp in a much farther forward position, then I think the bike will feel nicer. And I might be able to get the height I need for the 175 arms to feel better.
Fascinating!! Left Side: Counter Clockwise motion of the crank makes the relative motion of the pedal Clockwise, intuitively you might think (I did) the RH threads would be on the left..???? EDIT: I have researched, and it is due to mechanical procession. So indeed, that is why LH threads are on the left side.
Hola ,se que es un comentario viejo,pero yo también pensé que los sentidos de rosca en mis pedales no tienen sentido ,y no encontré explicación! Si pudieras explicar lo de "precesión mecánica " o compartir algún enlace al respecto te lo agradecería mucho. Saludos y gracias.
You could go closer, to the point where the two holes overlap but obviously not to much
What if you cut 20mm peace and weild it again???
I wanna do it but I dont know which length to choose. I was ridin 170, then switch to cheapest 150 and its much better but momentum is reduced by third. Im thinking about making 156, 157 or 158 but its just guessin. Maybe this could be calculated?
Pretty brave doing that without a drill press ....
It takes a steady hand…😂
they last or broke
Great mod! Do you think this would affect the structural integrity of the arm?
I think as long as the crank is used for it's intended purpose (50lb child riding in the 150mm length) I feel it will be more than strong enough. Trek actually specs most of their 20" and 24" mountain bikes with a dual position setup like this.
I definitely wouldn't feel comfortable with a larger rider or adult riding this setup in an aggressive manner, but it's my young daughters bike. She was on a 20" bike that she out grew, and this is a small 13" frame 26" wheel Trek mountain bike. She fits the bike ok, but the cranks were just a little long for her currently. If the crank mod works out, I'll probably get another crank in the appropriate length that I can set up in a 1x system (the crank I modified has a stamped non removable 3 piece chainring ). Thanks for your comment and question!
For sure it will impact it, but these things are over designed and cna carry massive loads so they won't fail under intended loads
I think the hole is metric so 13mm ?
I believe I used a 1/2" drill bit which is about the same as 13mm. The threaded hole size on all cranks other than the steel 1-piece type is 9/16".
@@JoeyMesa ok tha ks for that
Make a few more holes the arms, save weight for free