VBB disc conversion


I would like to convert my vespa VBB to a front disc brake.

may some one please tell me if I purchase the following from S.I.P below will I have trouble fitting it together. 

steering columns from SIP

Grimeca disc kit from SIP

bitubo gas shock from sip



Hi dude


can you post a picture ?



-- Let me tell you something about my expirience regarding bitubo and discbrake --



I know that if you mount a new brake with a new shock sometimes the thickness of the paint is to much.

If it´s like this you could modify a little bit to mount easily. Also the 2 holes have to be open a little bit. Round about a half millimeter.

I´m shure that your old shock will fit without problems with the brake disc.



Did you also purchased the special screw for mounting a bitubo with diskbrake ?





Hi appreciate the reply

thickness of paint is fine the bitubo slides into place.

My old shock is not compatible, it came from a drum brake and the motorcycle is a VBB

I will provide a picture shortly, it looks like about 3 to 4 millimetre if I line up the top  hole and have to adjust the lower hole. It just looks like a total mismatch

I did not purchase the special screw. Is this the screw for mounting the brake calliper so then it does not rub against the shock ?




Hello Dom,

Our inhouse technician posted a detailed description of the conversion in another part of this forum:


All the necessary parts are listed there, the additional information is in German however. Maybe this helps a little, if you need more information you can call our hotline and speak directly with our tech-wiz.



Hi thanks for the reply guys, I have recieved my parts and have come across a major problem, the mounting holes on my gas bitubo shock does not align with the holes on the Grimeca Caliper plate. Any help would be appreciated.



I converted my 1965 VBB 2T front forks (non Disc) to 10" px 20mm spindle type fork kit from sip and put a Bitubo gas shock on, not a straight forward bolt on ! but if you want photos or help post your email and i will try to help,



Hey Paul I will eventually get my picture up of the problem I am having but if you can post me your pictures of the mods you made to the shock would be appreciated, [email protected]