Dirt Road Blues 

To clarify this is in regards to downtube braze on levers. I want to install a set of Nuovo Record levers in place of the SLJ's.

Anyone ever tap those oddly threaded Simplex bosses to accept a Campy screw? 5x1 to 5x0.8 if I remember correctly.

Assuming that the tapping job was successful, how'd things turn out for you? Did the swap perform well for you?

I've read that it's difficult to keep things tight. Wondering if thread locker would help, or not.

Thinking of giving this a go on my PX-10, but want to hear from folks with firsthand experience before I go and do something I might regret.

seypat

I thought a version of Simplex DT shifters were the best that's ever been. As good as Johnny the fiddler who kicked Ol Scratch's a$$ back to Hades. Anyway, if you want to see if the Campys shift better, put them on a clamp on mount and give them a try. After that, make a decision.

Dirt Road Blues 

Certainly the retrofrictions are loved by many. I often read how they're "the best shifters ever made." And I can't disagree that they perform great. I've been riding with a pair for a couple months now.

To be honest though, my inclination to swap them out for Campy is more about completing a group set than anything else. And then there an aesthetic preference as well. I simply love a low profile lever, while wide protruding levers tend to irk me.

I would actually assume that NR levers will perform not quite as well as SLJ, but for my riding style, that's not much of a concern.

I just need to know if the Campy mounting/adjusting screws should hold dependably in a re-tapped boss or not.

seypat

You'll have to wait for someone else to answer the question then. I will say though, if that's a high level Pug that came with a high level Simplex group, a future buyer will probably want the complete Simplex group back on it. So, retapping the bosses will probably decrease the value.

Dirt Road Blues 

I get your point. And normally that'd be a consideration I'd hold too. And while it is a high end frame, it had most of its original parts changed out prior to my purchasing it. I also really feel this bike is a keeper. I'm enjoying it as much or more than anything else that has passed through my hands.

AdventureManCO 

Hmmm...I'm looking for some retrofrictions for my PXN10 and it has these on it...



Wanna trade?

daka

What is the compatibility between Simplex and Huret DT levers? Huret made some elegant, slender levers in the mid to late '70s with the Success group.

https://velobase.com/ViewComponent.a...0084a&Enum=104

oneclick 

I think you may find the Simplex boss
a) is too short;
b) has no flats; or
c) both of the above.

scarlson 

Aside from the above concerns, I would not tap to 5x0.8 from 5x1. It will be a mess. The thread pitches are so close that there will be nearly no threads left by the end of your tapping job. That's also what happens when you tap a French bb to English. The pitches are so close there won't hardly be any thread left by the end.

Dirt Road Blues 

​​After looking into it more, it began to appear that there's a bit of inconsistency regarding the subject. Conflicting reports. Surprise, right?

Anyhow, I decided to attempt a straight swap rather than leap right into making any permanent changes with a thread tap that may or may not have worked.

Turns out, at least in my case, that Campy levers install just fine on Simplex bosses without need for any modifications. Everything pressed right into place, and the screws threaded in easily and snugly. Should note that this is a '79 frame in case era makes a difference or not.


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himespau 

Glad it was that simple for you.

Charles Wahl

Calling Emily Litella . . .

Chombi1 

Simplex Retrofriction levers will usually have the same threading as Campys, as long as they are not the ones that came with a band clamp. The oddball threaded ones are the ones with the band clamp.