Bicycle Mechanics - Seat binder bolt for an old Univega.

Hi everyone,

I recently bought an old (early-to-mid 80's) Univega frameset, with a seat binder bolt sleeve I've never seen before. (I've attached an illustration of what it looks like.)

I bought a Sugino bolt for it, but it didn't fit.

What sort of bolt should I be looking for, and where can I find one?

Thanks!

Seb.

edit: It's not a jpeg! It's not supposed to be blurry! I swear, click on it!

— Oh, and measurements are in mm, of course.
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What are the sugino bolts dimensions?

I believe what you need for that frame is a M6 x1mm socket head bolt which would fit down into the recess of the seat binder. The other side would use a matching hex nut with 10mm flats. That is assuming the other side of the binder has a hex shaped recess and is not round. My Koga Miyata has the same setup. Bike Tools Etc sells them in lots of 10 in stainless for about $6.

http://www.biketoolsetc.com/index.cgi?id=416545615343&d=single&c=Repair-Parts&sc=Fasteners&tc=Socket-Head-Bolts&item_id=US-SS625

Hi.

Thanks for the response! I've attached another illustration... I'm having fun drawing these!

Seb.

e: The diameter of the bolt head and nut is 12mm.

Also, notice that the Sugino bolt has a little protrusion, which is supposed to fit onto a similar indentation on one side of a corresponding frame's binder bolt sleeve... My frame doesn't have that!
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Hi raverson,

Just saw your message. Unfortunately, no—both sides of the sleeve are round. But I suppose I can try it, though the nut probably would not fit, right? I would have to find a round nut, or make the hex nut round...

Thanks for your response.

Seb.

OK, I just made a drawing of what I need.

Now I've got to find it... or something close to it. :rolleyes:
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Campy makes a seat binder bolt with no anti rotate tab on the nut. Trek also used them on bikes from the late 80's. Hope that helps!

I have two 1986 Univega Gran Sprint Bicycles. I need a Seat Post Binder Bolt/Nut for one of them just like the one you describe. The problem is actually not the bolt, which I can find at my local fastener supply, but the nut. The OD of the nut that normally pairs up with the bolt (M6) is just a smidgen too big and will not fit inside the hexagonal holder of the seat tube collar. I need one that will fit. DId you ever find a source for this part?

Thank you!

Neil

I just ran into this problem after getting fed up with a loose seat post and my LBS fixed me up after many trips to and from my univega and the back of the shop, until he finally found something that would work. Not exactely sure what it was, but it kept my post tight from then on.