Marzocchi Brake Boss Thread Size

[Rob H]

I'd like to replace the brake bosses on my QR20 Bombers with some cap head bolts as I'm running discs and don't perticularly like having two studs sticking out the front of the forks. However I can't figure out what the thread size is, it looks about M5 but the pitch is too fine, rather than randomly ordering obscure bolts to try does anyone know what thread size these are?

My best guess is M6 by 0.75 can anyone confirm?

 

[mdvineng]

shop.brake-stuff.de/en/canti-studs

 

[Rob H]

Re:

Well ordered some M6 by 0.75 bolts and the thread was far to course, any other suggestions?

 

[Mugoftea]

Re:

Why not remove the canti studs and then measure the thread diameter & pitch?

 

[Rob H]

Re:

Do metric bolts still use TPI? Or is there some weird TPM or TPCM?

 

[focomat 1c]

Re:

Metric threads are either coarse or fine pitch

Your 6mm x 0.75 bolts are fine pitch. You can check the pitch on any metric bolt/screw by counting ten thread crests and measuring
the distance between them. In this case ten thread crests will be 7.5mm in total. The only other option would be that ten thread crests
measure 10mm ( which is coarse pitch )

I would remove the existing items ( as above ) and check your measurements again.

 

[Rob H]

Re:

Thanks, went back and measured the pitch, 10 teeth on the the stud are 7.5mm, as a sanity I also measured my "M6 x 75" bolts and it turns out that the company I bought the bolts of actually sent me M6 x 100 which explains why they didn't fit. Hopefully the correct bolts are on their way.