Urgently need to know Kona seatclamp size

I've stripped the threads on my wife's 93 Hahanna seatpost clamp and have no verniers (still!). Can anyone tell me the size as I need a new one for the weekend.

Cheers

Pretty sure it'd be 28.6mm - same as the front mech....

SP

Splatter Paint":22g7zhki said:

Pretty sure it'd be 28.6mm - same as the front mech....

SP

Click to expand...

That would indeed make a lot of sense :facepalm:

Splatter Paint":37w1ed9k said:

Pretty sure it'd be 28.6mm - same as the front mech....
SP

Click to expand...

That may be correct in this case, but in higher-end frames the size of the fm clamp isn't the same as the seat clamp because the seat tubes are externally butted out to 29.8 at the top and where the welds are. It may be though that a Hahanna has a plain gauge straight seat tube, in which case you'd be right, but I don't know anything about Hahannas I'm afraid.

I'm saying 29.8/30mm for 1993. Is it a 27.0mm seatpost?

You can measure to 0.2mm easily enough with a steel rule, so that should put you in the ballpark or else wrap a strip of paper round the top of the seat tube and mark where it overlaps.
30mm dia. will be about 94mm, 28.6 around 90mm.

Andy R":1bm13l7h said:

I'm saying 29.8/30mm for 1993. Is it a 27.0mm seatpost?

You can measure to 0.2mm easily enough with a steel rule, so that should put you in the ballpark or else wrap a strip of paper round the top of the seat tube and mark where it overlaps.
30mm dia. will be about 94mm, 28.6 around 90mm.

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Pretty sure the seatpost is pretty skinny, maybe a 26 something

In that case it'll be 28.6mm then

The mathematical constant Pi (3.142) is the relationship between a circle's diameter and circumference. Therefore simply measure the external circumference of the seat tube (if you don't have a flexible tape measure you can wrap some paper around and mark it, or use a bit of string) then divide that measurement by 3.142 to get the exact external diameter of the tube.

Or... an engineering shop might be able to drill and tap your existing clamp for the next larger thread size, looks like it might be possible on a standard Kona clamp. A decent engineering shop will probably have the appropriate sized replacement allen bolt too..

RadNomad":irlauf87 said:

The mathematical constant Pi (3.142) is the relationship between a circle's diameter and circumference. Therefore simply measure the external circumference of the seat tube (if you don't have a flexible tape measure you can wrap some paper around and mark it, or use a bit of string) then divide that measurement by 3.142 to get the exact external diameter of the tube.

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Mmmm - could have sworn I said much the same this morning

Come on then raidan73, tell us the size!

SP