What do you call them?    I’m referring to the things at the top of the seat stays on your bike frame.   Are they seatstay caps?  Ends?  Does your bike even have them?  Speedhounds do, and we like to call them by the old British term, “top eyes.”

The Speedhound seat cluster, with its scalloped "top eye."

Contrary to popular opinion, seatstays are the least important tubes on a bike frame.  They add virtually no lateral stiffness and take almost all of their load in compression.  That’s why you can use skinny tubes without compromising the frame’s integrity.  It’s also what gives framebuilders the freedom to get creative where the seatstays  join at the seat cluster.

Using decorative top eyes is one way we’ve added some personality to the Speedhound ONLY ONE frame.  Joining the seatstays to the side of the seat tube also gives the Speedhound wider spacing for fenders and fatter tires, so there’s a functional advantage as well.

If you examine our top eyes, you might suspect that they are simple plugs inserted into the seatstays.  Someone even asked whether they might push in if they hit a hard bump!  But take a look at the raw top eye — it has a shoulder that snugs up against the end of the seatstay. Very clever!

The top eye plugs into the seatstay end.

Our seatstay end (left) and top eye (right).

Our top eyes are investment cast steel, with a deep hollow for weight reduction and better brazing.  The joint is cleaned up before the seatstays are attached to the main triangle.  The result is a seamless connection that sets Speedhound apart from the typical production bike.

Top eye and seatstay, together at last.

Next time you pass by a rack of parked bikes, take a look.  Are there any top eyes peeping back at you?