Originally Posted by
Jantaras
Hello,
so I was building this Monark Reynolds 531 for selling. I bougt it as a frameset and it already came with a beer can shim between race and fork.
The seat of the fork is too small for most of the crown races I have. Seat is 25,8 mm and race 26,4mm. Crown race sits very loosely.
I thought about the possibilities I have:
- sell the bike with the beer shim and state that in the add. Now, I know it is not ideal, but what are real dangers of that? The crown race may become loose, but it is not that it will disintegrate or become locked, so are there any dangers while riding it?
- I doubt knurling the steerer seat would help as there is significant gap (can see in picture)
- seat the race with metall putty, but still, it could easily get seated eccentric as the gap is significant
Originally Posted by
Jantaras
- I have this Prior/Maillard headset that is quite heavy and finish is not very good, I believe intended for basic city bikes, but the race is ideal in size and stack looks good. The problem is that the adjustable race and locknut is too small for the steerer and would not thread. Also, thread pitch is different (french?). One possibility is to retap these headset parts with 1" tap if it is possible.
The French made Prior/Maillard headset is most likely metric with 25mm x 1mm threads - smaller than an ISO/British thread headset with 25.4mm x 24TPI theads. The headset is chrome plated hardened steel - about 60+ Rc hardness. Not re-tapable because the tap is likely going to be 60 Rc too plus the chrome plating will tear up the tap.
Suggestion, find an inexpensive ISO or British 1" x 24TPI headset. Before you spend any money try a headset that size first. There is a possibility that the frame takes on old British size 1" x 26TPI headset.
Originally Posted by
Jantaras
Now, a bonus question: could someone explain Sheldon Brown's cribsheet for me?
It states, for example, that 1" ISO crown race is 26,4 mm and steerer 25,4 mm. Thats 1 mm diference. Does that mean that steerer diameter is measured above the seat for crown race?
https://www.sheldonbrown.com/cribsheet-headsets.html
Yes, the steering tubes are smaller that the crown race.
British and Italian size headsets fit 1" (25.4mm) diameter fork steering tubes. The crown race is usually 26.4mm or 26.5mm diameter. I've never seen a 25.8mm crown race on a standard type of frame like yours made of better quality tubing like Reynolds 531.
French steerers were 25mm and most used a 27.0mm crown race. Same with many Japanese bikes.
As far as your crown race problem, you might try to find .3mm shim stock and cut it to fit. Assemble it with some liquid bearing retaining compound for Loctite-Henkel.
verktyg
