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Plastic in MAFAC brake levers 
PostPosted: Mon Jun 30, 2008 6:42 am Reply with quote
vanhelmont
Joined: 11 Dec 2007
Posts: 242
Location: Florida
My MAFAC Racer levers have black plastic around the pivot and for the adjustment mechanism. Does anybody know if it's the same stuff as the delrin in Simplex derailleurs? Are these levers safe to use? I broke the plastic parts in a Dia Compe lever once while squeezing the lever a bit hard just to make sure everything was in good shape. Better in the garage than on the road. The MAFAC plastic parts look more substantial than the Dia Compe part thsat failed.
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Plastic Brake Lever Parts 
PostPosted: Mon Jun 30, 2008 10:45 am Reply with quote
verktyg
Joined: 14 Jan 2007
Posts: 2814
Location: SF Bay Area
Mafac used plastic in their brake levers for many years. The first ones that I recall were the Guidonnet style levers used for French touring bikes. They had white plastic wrap around levers. They also used plastic lever handles on their Ville Forge levers for upright bars.

In the mid 70s Mafac introduced their standard drop bar brake levers with main part of the lever body made of plastic. They replaced the old style all metal levers that had the half rubber hoods.

Later they started using these plastic parts on their top of the line brake sets that had full rubber hoods covering the plastic body. The black portion of the levers in this picture were made of plastic:



I've never seen these fail other than the adjuster screws breaking from some kind of impact. I'm not sure what kind of Plastic Mafac used. It seemed a little harder than the DuPont Delrin (nylon) Simplex used in their dérailleurs.

Modolo and even Campy produced some models of brake levers with plastic bodies. They are probably safe as long as there are no cracks in the plastic.

Chas.
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Delrin 
PostPosted: Mon Jun 30, 2008 3:42 pm Reply with quote
greyhundguy
Joined: 09 Apr 2008
Posts: 678
Location: South-Central VIRGINIA
Got curious...

http://en.wikipedia.org/wiki/Polyoxymethylene

"Applications" section is interesting.

Jay

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I've been wrong for 35+ years!!! 
PostPosted: Mon Jun 30, 2008 8:09 pm Reply with quote
verktyg
Joined: 14 Jan 2007
Posts: 2814
Location: SF Bay Area
Jay,

Great link. I guess I've been wrong about Delrin being an improved form of nylon for the past 35 years. That's what I read somewhere years ago and I've seen it repeated in technical sources over the years. Not even close. They're completely different plastics.

http://en.wikipedia.org/wiki/Nylon

Chas. Crying or Very sad
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Thanks 
PostPosted: Mon Jun 30, 2008 9:46 pm Reply with quote
vanhelmont
Joined: 11 Dec 2007
Posts: 242
Location: Florida
It sounds like they are safe to use. They surely aren't delrin because the plastic doesn't seem slippery. My other bike has Campy levers with some plastic in them, which seem very solid.
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PostPosted: Tue Jul 01, 2008 4:37 am Reply with quote
greyhundguy
Joined: 09 Apr 2008
Posts: 678
Location: South-Central VIRGINIA
I got a pair of the Black Plastic housing levers as a bonus of sorts. I bought a Stem, bars and brake set to get the stem. Everything in Alloy was kinda beat up, but the plastic housings looked almost NEW. 30 (?) years of use...they must be sturdy.

I looked up the Delrin thinking it might be related to the "Rislan" that Ideale used for their 2000 series saddles.


Jay

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Plastic in MAFAC brake levers 
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