gear lever boss diameter?

[foz]

Can anyone tell me what diameter the circular part of a braze on gear lever boss should be?

I'm trying to fit campag barend shifters to the braze on bosses, but they don't want to go on all the way. The frame is fully chromed which I suspect may have made them slightly larger diameter than they should be.

Would like to know the correct diameter before I start filing though!

thanks!

 

[keithglos]

I used these in the 1950s, if yours are the same they are a totally different shape from down tube levers. Certainly the centro bore is smaller. Never occurred to me to measure them.

From what little I remember

Keith

 

[foz]

Thanks Keith, but my levers are 9 speed indexed barends, from the early 00's

 

[foz]

Forgot to add - the bosses are standard campagnolo style (from the early 90's)

At the moment my choice of gear levers is between

- simplex retrofriction (seem to have a very long lever throw to move the chain over an 8 speed cassette)
- campag 9 speed bar end shifters (only indexed, no friction mode - I have a mech that should be compatible and a 9 speed cassette)
- C Record friction levers (only friction)
- Dura Ace SL 7700 9 speed levers (can be used indexed or friction)

I've tried the simplex, but the lever throw is too far I think. C Record friction will probably have the same problem. DA are nice and should play nicely in friction with anything, I'm just not sure they fit the rest of the build. Campag bar ends are lovely, but they won't fit the bosses (at the moment) and can only be used 9 speed indexed, not friction, which might limit my wheel choices in the future...

 

[Midlife]

I'm confused, are you trying to fit the levers from a bar end onto the bosses on the frame?

Shaun

 

[foz]

Yes. From what I've seen, the Campag 9 speed barend shifters are just a DT lever on a boss, so they should go on fine

 

[Midlife]

I'll dig out the digital micrometer and measure some of the bosses on the frames I have in the garage....

Like Keith, my memory of the 70-80's is that the bar end levers were shorter and broader than the downtube levers.

Shaun

 

[Midlife]

Quick check of a few frames with varying thickness of paint gives 8.88mm to 9.07mm diameter of the downtube bosses.

Shaun

 

[foz]

Thanks Shaun! Will check the diameter of mine tomorrow

 

[Midlife]

Quick check on my downtube levers (Campag, Shimano, Suntour) and the internal diameter is near on 9mm for them all.

BITD we adjusted the levers as they are alloy and easy to slighty "enlarge". Very fine wet and dry spun around the finger but crucially finished with fine corundum paste on the lever boss spinning the tight lever around. Easier than trying to remove chrome plate.

Shaun