How big (diameter) are the two bolts that hold the two seat pieces together?

[Vargas]

I have lost them while riding the bike. Have no idea how it happened. When I returned home they weren't there

 

[Vargas]

Of course I noticed there was

Of course I noticed there was something going on with the seat but at first I thought it was just the clamps which needed some tightening.
Fortunately no accidentes, and yes, after this I have rechecked all bolts.

 

[John Tolhurst]

Never heard that one before!

Never heard that one before! They are M6. The holes are 6.5mm, so a 1/4 bolt might fit. Make sure they have a nyloc nut on them, so they don't vibrate loose.

 

[Vargas]

Thanks John

1/4 which is 6.35 mm does fit well. I have replaced the missing ones by 1/4 bolts the same day I lost them. Anyway I'll have to go buy the nyloc nuts and will look for the M6s.

 

[Jerrye]

Metric bolts & nuts

If you have a Lowe's or Home Depot near you they should have the M6 you are looking for in their hardware section, normally in the metal cabinets with drawers.