Contigo

I'm interested in a certain PX-10, which would be my first French bike. I've read a few things about Simplex derailleur hangers, but I'm unclear on when or how that hanger could be used with a Huret derailleur.

If a picture is worth a thousand words, perhaps what I should really ask is What's going on here?

Mr. 66

jj1091

Hard to tell from the photo, but a full pic of the bike would be helpful, since it looks like either the chain is off the smallest cog, or it's very-small 6th gear. Could be that the chain is off the sprocket, which is why the rear derailleur looks in the wrong position for the bike.

dddd

I had a Trek 710 with the Duopar having a broken tab washer, so the derailer was kept bolted solid at a fixed angle to the dropout.
It made for a very interesting tire change, not impossible but difficult, and with the QR shaft having to be removed.
I even clearly remember the last flat rear tire repair, ran over the latch of a small belt buckle along a short bike lane on I-80.

Aubergine 

dddd

Perhaps the seller should in that case be reminded that the plastic cover plugs into the hollow mounting bolt and is easily broken, so must be pushed out from the back side.
...and that there may be a smaller expander bolt threaded into the back side of the mounting bolt, and which needs to be removed first from the back side.

Contigo

Great point -- this is exactly what I'm getting at. Seller is not a French bike person, and I can't inspect the bike in person, so I don't really know what is going on with the hanger. Your idea that maybe it was bolted solid is something that I wouldn't have thought of, but seems plausible.

Here's the whole bike:



And here we have another angle:

dddd

There are certainly a LOT of Duopar derailers out there which lack an intact tab washer of the correct (for dropout type) style.

The washers were hardened after bending, which increased their yield strength sharply, but which made the part brittle at the limit.
I can still almost hear the echo of the "snap" I heard when I broke mine in mid-80's, but have been lucky in recent years to acquire a couple of complete units having Campagnolo-type washers.

Used-bikes having C-Record or similar derailers should also always be inspected for a properly swiveling pivot, as broken stop hardware can be hidden by rigid mounting the derailer using a thicker washer.
One seller last year (a medical doctor no less) acted offended that I immediately checked the bike he was selling for proper swiveling, took a rigid stance as soon as I discovered his camouflaging of the broken part! I walked away without saying a word.

nesteel 

There will a batch coming this month. I also just sent you a PM regarding loaning me the Huret dropout version of the tabbed washer.

Dieptriest

Hi Contigo,

That rear derailleur looks like it's reached his end of life and the cable to it is also to short or not matching this kind of derailleur.

The bike is late 60 early 70's i think (black detailed lugs). the rear derailleur is an 80's replacement?
Ask the brand of the front derailleur and look for a matching model, than you have a (more) authentic PX-10

John E

Yes, decals look like late 1960s, making this a pretty valuable PX-10. I had no trouble hanging a SunTour Cyclone on my 1980 PKN-10, but by then the Simplex dropouts had changed quite a bit from yours. Tightening the mounting bolt to maintain the derailleur body in a fixed orientation is not that bad a strategy, particularly if you carry the necessary hex key with you.