Confused Mom/ Tap and Die Question...

If the parts in question are a crank with a through hole and a bolt, the simplest solution would be a new longer bolt to protrude though the back side of the crank and a nut.

Edit: (It's been sixty years since I dealt with anything with pedals)
 
Consider your long term goals with this moped, repairing the arm could be expensive. If the crank arm is removable from the spindle or if the spindle can be removed from the bike with this pedal attached, I'd install the stripped pedal and weld the backside. Pick up a replacement part at a later date, things are always available when you don't need them!
 
I never thought I'd receive the kind of response I have, so quickly. Thank you to everyone who's attempting to help.

One of the solutions we tried previously, was to buy a 1/2" diameter carriage bolt, insert it through the opening and just tighten it down with a washer and nut but the head of the carriage bolt protrudes by a millimeter or two past the opening closest to the engine and interferes with the kickstand.

The pedal arm where the pedal screws into is only about 1/2" deep; it's a very hard steel. I'm hoping a 1/2" depth is enough to hold an insert. Yes, the male thread is also damaged. The crank and arm are one piece and it's on the right side. Although this moped is a 1977 Puch Maxi, I thought the thread size would be in inches because my son ordered a replacement pedal a while ago and the size was 9/16ths.
 

Attachments

  • IMG_20210313_095833243_BURST001.jpg
    IMG_20210313_095833243_BURST001.jpg
    1.3 MB · Views: 52
  • IMG_20210313_095853311.jpg
    IMG_20210313_095853311.jpg
    2.5 MB · Views: 51
  • IMG_20210313_095930433.jpg
    IMG_20210313_095930433.jpg
    1.6 MB · Views: 52
I’m sorry if I’m going to sound stupid but from long years of trying to help folks I’ve learned to start with the obvious. So did your son order from a Puch dealer or just get a bicycle pedal? The 70’s, especially the late 70’s there was all kinds of confusion about hardware even with American stuff.

did the new pedal ever thread all the way into the crank arm? It doesn’t look like it by the pedal threads.
 
Hi June: You might want to try a glue repair- an epoxy cement may well be strong enough to hold the stripped pedal shaft into the stripped crank hole provided you clean both parts really well with a solvent like lighter fluid first. You could possibly improve your chances by winding some thin wire around the pedal shaft threads also before gluing to fill the space a bit more
-Mark
 
This part?

www.dennycycles.com

Chrome Pedal Arm Set for Puch Maxi

We sell moped parts for Puch, Tomos, Vespa & More. Fast same day shipping on orders placed before 2PM EST Monday - Friday
www.dennycycles.com www.dennycycles.com

If that is not the right part I'll bet one of these moped stores would know where to get it. The original part would best be repaired by adding weld material to the inside and re-tapping. Should be 9/16" as someone said earlier. I do not have such a tap or I would offer to do it.
Robert
 
Last edited:
June said:
I never thought I'd receive the kind of response I have, so quickly. Thank you to everyone who's attempting to help.

One of the solutions we tried previously, was to buy a 1/2" diameter carriage bolt, insert it through the opening and just tighten it down with a washer and nut but the head of the carriage bolt protrudes by a millimeter or two past the opening closest to the engine and interferes with the kickstand.

The pedal arm where the pedal screws into is only about 1/2" deep; it's a very hard steel. I'm hoping a 1/2" depth is enough to hold an insert. Yes, the male thread is also damaged. The crank and arm are one piece and it's on the right side. Although this moped is a 1977 Puch Maxi, I thought the thread size would be in inches because my son ordered a replacement pedal a while ago and the size was 9/16ths.
Click to expand...

From the photos, the male thread will have to be repaired or replaced as well. The crank doesn't have a lot of material, making use of an insert problematic. From this Puch crank, it appears that the crank can be removed without removing the pedal
www.mopeddivision.com

NOS Puch Maxi S Pedal Crank Arm Assembly, One piece - Chrome

International Hunter and Seller of Vintage Moped Parts for Puch, Tomos, Motobecane, Mobylette, Vespa, Piaggio and other 2 stroke 50cc motorcycles.
www.mopeddivision.com www.mopeddivision.com

Welding the pedal to the crank as @Firstram suggested may be the most expedient way to make this repair. A new pedal bolt and building the hole in the crank up, drilling and tapping would be a more elegant solution.
 
In response to some answers:

My son did order the pedal from Moped Division, a moped supply company; Puch is a defunct business since the 80's. The pedal did thread all the way into the crank arm. The crank and arm are "one" piece. Even though Moped Division shows a replacement part on their website, after contacting them, I was informed that they haven't had this part in years. Yes, the pedal threads are damaged as well.
 
You must log in or register to reply here.
Back
Top