brianinc-ville

These Mafac guidonnet levers came to me on, of all things, a Raleigh Superbe. I was thinking I'd like to use them with moustache bars on a city build (Takara touring-ish frame, Sturmey 5-speed hub) -- but I'm a little nervous about whether the ≈40-year-old plastic is going to snap off in my hand. The end of one lever was already snapped off, when I got it. This thread says that they've got a metal frame inside, and thus can't totally break off. Anybody know whether that's true?

dddd

One thing about braking components is that you can staticly test them to more cable force than they are ever likely to see in use (barring a crash!).

An exception might be for an instance of some extreme loss of brakepad friction, such as with rain on steel rims. I once rode a Varsity on wet grass, then felt the bike continue to accelerate as I applied the brakes hard on a descent, which was terrifying.

Plastic levers seem to normally have a steel shank inside, though I've seen the clamping portion of cheap MTB levers fail completely and with no metal reinforcement there!

Lascauxcaveman 

That looks exactly like the pair I sent @noglider awhile back, complete with missing knob on one lever. I was afraid to use them and took them off my wife's Peugeot mixte in favor of some sturdy, modern Star BMX type levers.

I know he's used these plastic levers on at least one build; maybe he'll chime in and let us know whether he's ever broken one.

noglider 

I broke the aluminum part of one of those levers immediately after receiving it. D'oh! I suspect these levers are not as well made as others, but you should use them while you last. I wouldn't be afraid.

Grand Bois

I didn't trust them when they were new.

loky1179

I picked up a pair of plastic Mt Bike levers, new, for about $3 on closeout from a shop. When I finally decided to upgrade to V-brakes, I also decided I didn't trust these plastic levers! (especially for winter riding).

They'd probably be OK. I still have mine in the parts bin. Even if they broke, what are the odds that they'd both break at once AND cause a crash? I guess that is the unknown.

In my younger, poorer, days I'd have used them. I've gotten more cautious with age.

ThermionicScott 

So you'd guarantee them to last roughly the life of the user?

gioscinelli 

I've had mine for 40 years! Used to take out my youngest daughter, go up a hill and down and she would say "do it again". Now I'm using the same Peugeot Mixte (gave to my wife long time ago) for my granddaughter who by the way is my youngest daughter, daughter! Same brakes Mafac with the plastic levers.

Trakhak

Plastic?!!?! The levers are steel covered with miracle Delrin, if you please. That's how MAFAC and Simplex referred to it in catalogs in the mid-1960s, as I recall. Why Peugeot didn't simply dip the bike in a vat of the stuff is one of life's mysteries.

SJX426 

Have you ever seen Delrin burn? You can use it to start fires.

Chombi

I dunno what's all the mystery about the French and Delrin.........as if one ever watched the movie "Mon Oncle" one will notice the post war French obsession with plastics.......

verktyg 

Like the Chevy Corvair... Unsafe at any speeds!

A lot of French mixties came with those MAFAC Ville Ref 718 Delrin levers.



I've seen broken ones on customer's bikes and I've broken at least one while doing a tuneup.

MAFAC made an all aluminum version, the Ville Forge Ref 725. They were a lot more robust.



The plastic levers were a very cheap, wimpy design. Add to that, most of them are at least 30-35 years old and Delrin deteriorates when exposed to UV rays as in sunshine!

We used to replace them with these Weinmann levers which were much better constructed.



MAFAC also made guidonnet style levers for randonneur bikes. They allowed easy reach while riding on the tops of the bars.

All metal Ref 820 levers,



They also made a version with plastic levers which were even less safe than the Ville Ref 718 levers!



No dental plan can replace your natural teeth and reconstructive facial surgery is expensive.


verktyg

Chas.

verktyg 

In the 1950s plastics were the miracle materials. In the US by the mid 60's plastic became the epitome of cheap!

" Just one word... Plastics..."

https://www.youtube.com/watch?v=PSxihhBzCjk


verktyg

Chas.

noglider 

I bet these levers, similar in design, would last longer.

Tbone5

I just took a pair of those off a pug mixtie. There is indeed a metal lever inside the plastic, about 3/5 the length of the lever in plastic. If it were me, I'd toss them and replace with a full metal lever.

JohnDThompson 

The plastic MAFAC guidonnet levers I have here have a steel core over the plastic, so they're perhaps a little safer than the all-plastic "Ville" levers. That said, I prefer the solid aluminum ones, either from MAFAC or CLB.

brianinc-ville

Interesting. How do you tell the difference? Are the ones in my photo above the all-plastic model, or the aluminum-shank model?

nlerner

I've seen a couple of broken sets of those in which the metal innards didn't go all the way to the knob on the end, so when they broke off they were particularly sharp and uncomfortable. Not a good design.

Ex Pres 

Any experience with the drop-bar non-aero version? mod 130 (from velobase)

dddd

Just like the petroleum age changed life on earth forever, the discovery of moldable, structural petroleum products opened up a can O'worms.

It seems like the limited lifespan of plastic bicycle parts has long been considered appropriate to the intended lifespan of bicycles, and if someone wants to use their bicycle longer than that the industry is all to happy to sell them replacement parts.

Seeing a current WalMart bike's plastic brake lever perch break in half tells me that not much has changed, though I think that current plastics can be made to withstand the effects of aging longer.
The current Ultegra rear derailer uses a molded plastic "A"-knuckle that is deemed strong enough, and even Campagnolo's Ergo brake lever bodies are molded of composite as well.