branko_76 

I supposed most would have tossed these in the trash, and I was tempted to do so as well but I'm glad I didn't. Although they were stiff and unresponsive, it didn't take long at all to get them working again...

branko_76 

I was lucky to find in my stash a pair of Shimano pulleys with the same bearing hole size (6mm) as the originals...

Nubra 

Hi there,
Love the exploded components!

I was dealing with exact same components on a low end Peugeot that I put back into working order (see my thread "save from the dump, now what" in classic and vintage). I can see a crack in the acetal resin in the FD already, so be prepared for it to fail pretty soon. Some one on my thread suggested using a couple of zip ties to reinforce it, but for me it was too late, broke completely. My RD was fine.
Very cool. I do like fixing up old bikes that have plenty of ride left in them.
Mine went to a young woman who wanted a ride around the neighborhood bike.
Cheers!

branko_76 

The front derailleur has a couple of cracks so I know its days are numbered. I got them working yesterday and they shift nicely. I won't get a chance soon to try them on the road because I ran into a problem with the frame. I may use the Simplex setup on a different bike.

Piff 

What's wrong with the frame? The restoration was going so well.

branko_76 

I got the stays where they should be but the problem became worse. The wheel is centered perfectly between the chain stays but is about 3/8" to the left of the rear brake center bolt. I tried a different wheel, even flipped it around in case it wasn't dished properly but same thing.

After taking many measurements, I found that the left chain and seat stays are about 1/8" longer than the right. I can also see that the wheel is not parallel to the seat tube, it (wheel) leans to the left when viewing from the rear. The only way to center the wheel would be to shave 1/8" or so off of either the "inside top of the left drop-out" or "inside bottom of the right drop-out".

Shaving the inside bottom of the right (drive-side) drop-out would be preferable I think, since it will have a derailleur hanger attached to it which would still be the correct size for the axle and keep it (axle) where it needs to be.

Mr. 66

I have a Mercier that has a similar seatstay issue. I may braze a metal shim on the dropout to remedy the issue.

branko_76 

Well, it just happened...

branko_76 

I was a little too heavy handed with the mounting bolts...

branko_76 

I found another in my stash and cleaned it up. I applied a little lock-tite to the mounting bolts so that I wouldn't have to over-tighten them...

branko_76 

Next problem....

When I tried to install the rear portion of the derailleur, I noticed that the diameter of the derailleur body was slightly smaller than the seat tube.

The seat-tube diameter is 28.6mm, the inner diameter of the Simplex derailleur body is 27.8mm. Since it's plastic, I could force it on but it would no doubt crack sooner or later.

branko_76 

...a ratty old HURET to the rescue...

nlerner

I recently installed one of those Huret FDs on a bike. Heavy as heck, but they work really well. Just a very solid/positive shifting feel.

branko_76 

I'm looking forward to trying it. It's about 20 grams heavier than the Simplex, but mounted on the Grand Prix, I don't think it will be noticeable.

noglider 

I agree that the cheap crappy Huret derailleurs of that era work really well, and they're durable.

branko_76 

What makes them "crappy" if they work well?

repechage

I would not ride a bike with the front mech like that. It WILL fail, and more than likely launch the cage into the chain. Replacement required, now.

repechage

Only problem with Huret front mech's is that one really needs to limber up the pivots, I back out the adjusters quite a bit, work oil and or graphite lock-eze into them- by backing out the adjuster a bit, the mechanism can be hyper extended and then will work better when adjusted back. Often these get "draggy" near the end of the travel otherwise.

Nubra 

so sorry brother. What is happening with the frame? You said problems there too?

branko_76 

I got the frame issue worked out but then the derailleur snapped. Not a big deal, more work but I'm learning something every time walk into my shop.

https://www.bikeforums.net/classic-v...alignment.html

noglider 

They were cheap and look cheap. As @repechage points out, they need occasional work to make them operate well. That's not so bad.

branko_76 

Most bike components need periodic maintenance, a good mechanic would know that.