Are disk and drum forks the same?

[ArmandTanzarian]

Hello,

I'm converting my old Vespa to a disk brake. I'm going to use a ScootRS hub as it looks more like the original rather than the star shape of the newer Vespas.

Are the stub axles of disk and drum forks the same? I bought some PK disk forks in anticipation of using a genuine Vespa hub but now it occurs to me that the Scootrs hub is designed for retrofitting to a drum brake fork. Will it still fit on a disk fork?

[rapido230]

the only visible difference is no hole in fork stem for brake cable. The forks are the same otherwise, but dont mistake earlier px forks for latter pxe as earlier forks had a smaller diameter spindle (16mm i think and later 1s are 20mm).

[rapido230]

oh, and do believe the pk forks are 20mm

[jonny snatchsniffer]

but not early pk50 forks as they are like primmy/50 special forks, but the fork leg is longer, there are a few discbrakes for smallies one of which is the scootrs one which uses the 4 stud hub, and can be fitted to early pk 50 forks and v range forks, the spindle is the same just different hub and backplate, i have some bare v range forks and some complete early pk50 forks so if your pk forks are the 20mm px type and you want to keep the older look id happilly do a swapsie with ya for whatever suits your needs, bearing in mind the pk forks give a ride height about 1" higher than the v range forks, both i believe are suitable stem wise for pre px models tho dont hold me to that

[ArmandTanzarian]

but not early pk50 forks as they are like primmy/50 special forks, but the fork leg is longer, there are a few discbrakes for smallies one of which is the scootrs one which uses the 4 stud hub, and can be fitted to early pk 50 forks and v range forks, the spindle is the same just different hub and backplate, i have some bare v range forks and some complete early pk50 forks so if your pk forks are the 20mm px type and you want to keep the older look id happilly do a swapsie with ya for whatever suits your needs, bearing in mind the pk forks give a ride height about 1" higher than the v range forks, both i believe are suitable stem wise for pre px models tho dont hold me to that

I've sorted the ones I've got now so I'll think I'll stay with them.

Cheers