Hi, this is an Italian folding bike from the 70s "piknik" and it has strange stem diameter and handlebar clamp diameter, I'd love to replace the headset so I can use a more modern standard iso fork/stem/bar, I'll copy the current headset measurements below. This is a 20inch wheel fork, and I'd love to put a larger 26inch fork with a disc brake ideally, cuz the current rim brake is very weak, also it would look sick. Is this feasible? Not sure exactly how to take a measurement of the head tube.
Stem diameter is 20.9, maybe 21, but not 21.1mm.
25mm diameter threaded part at top of steerer (not 25.4mm)
by burner_1234567891011
1 Comment
* this is incorrectly assembled, there should not be a lockring over the clamp
* [the dimensions suggest a french headset](https://www.sheldonbrown.com/cribsheet-headsets.html)
* no you are not, that massive change in axle to crown length will ruin the handling and destroy your frame by stressing the frame in ways it was never meant to experience
* the puch picnic is a clone of the [raleigh 20](https://www.sheldonbrown.com/raleigh-twenty.html)