Bike Forums

Bike Forums (https://www.bikeforums.net/forum.php)
-   Classic & Vintage (https://www.bikeforums.net/classic-vintage/)
-   -   Mercier 300 (https://www.bikeforums.net/classic-vintage/1168696-mercier-300-a.html)

juvela 04-08-20 07:50 AM

-----

thank you for the response to queries

P3 crown race is 26.9

total stack height is 34.0

[values from Sutherland]

-----

Narhay 04-08-20 07:57 AM


Originally Posted by juvela (Post 21407026)
-----

thank you for the response to queries

P3 crown race is 26.9

total stack height is 34.0

[values from Sutherland]

-----

Thanks. I just checked the box for the Tange I used on the Gitane and it was 27.0 and fit fine.

juvela 04-08-20 09:18 AM

-----

stack height -

if you plan to stay with sidepull brakes for the build you will have the two "free" mm's to play with for the replacement lower stack from the thickness of the MAFAC hanger.

---

years ago there was a replacement sealed bearing lower stack available as a separate item. it was called the Jasik but was offered for only a short time ca. 1978-79.

-----

Narhay 04-09-20 02:25 PM

I replaced the lower cup and race with one from a spare frame I had here but it wasnt perfect. The adjustment is still off so it looks like I will be on the hunt for a French threaded headset, either the Stronglight P3 or Competition. If anyone has one lying around let me know.

juvela 04-09-20 04:32 PM

-----

be aware that the Competition V4 requires five and one half more mm of steerer than the P3

if you stay with sidepull brakes you are gaining about two mm over the OEM arrrangement

this still leaves you about three and one half mm short for full engagement of the V4 locknut

the V4 fork crown race is another complication. its interior is stepped so that the seat needs to be of lower height than for the P3 whose fork crown race is not stepped.


-----

Narhay 04-20-20 09:41 AM

I measured the steerer and head tube and came back with 35mm of room for a headset. There are some early generation metric dura ace and 600 headsets on ebay with stack heights of 38mm. Wondering if I remove the washer between the lock nut and the threaded cone if I would have enough thread engagement.

steve sumner 04-20-20 04:14 PM

hate to see my all time favorite stem abused like that! 3ttt is 26.0 and French al-alloy bar is 25.4.
cast alloy parts have no elasticity. I see so many 3T/Cinelli combos out there and I just cringe.
stem failure is no fun! as for headsets: I see basic steel French headsets on ebay from time to
time with really low stack height. if you want better quality the Stronglight Delta was pretty short

Aurorabucky 04-30-20 12:03 PM


Originally Posted by steve sumner (Post 21429910)
hate to see my all time favorite stem abused like that! 3ttt is 26.0 and French al-alloy bar is 25.4.
cast alloy parts have no elasticity. I see so many 3T/Cinelli combos out there and I just cringe.
stem failure is no fun! as for headsets: I see basic steel French headsets on ebay from time to
time with really low stack height. if you want better quality the Stronglight Delta was pretty short


A word to the wise, since there's an Italian stem in there already, check that you even need a French stem. My Mercier buildup was matched to a Gitane fork, so this well may not be true for your Mercier fork, but my French Nervor steerer was sized to fit a 22.2 stem, not a 22. [MENTION=333224]juvela[/MENTION] can comment on this, but apparently some of the steerer boring was done pretty imprecisely.

​​​​​​If you haven't already, see if a regular old 22.2 will fit in there, or else you might get a French stem only to find that you can't get it to fit right.

Narhay 05-03-20 11:02 AM

A regular 22.2 stem did fit, I noted this shortly after purchase. A nice surprise.

I don't do quill pedals...sorry 14x125 threads.

Foreground
https://i.imgur.com/l3EgrkL.jpg

Background
https://i.imgur.com/TxPMSK7.jpg

steve sumner 05-03-20 11:16 AM

I think that bike is crying out for a white pump and bar tape

Narhay 05-03-20 12:35 PM

https://i.imgur.com/QnDtRpI.jpg

Tapping successful. Gave it a quick hand polish and clean. Next up chainrings.

juvela 05-03-20 01:56 PM

-----

tapping out a first generation set like this probably not the smartest thing

first generation has a tendency for radial crack failures at the pedal hole

you have just removed a bit of "meat" in that spot...


-----

Narhay 05-03-20 04:52 PM

Understood and it was something I considered. However, I assume the crank arms were not forged differently between 14x125mm and 9/16-20 versions other than drilling and threading so this would likely be no different in terms of risk tolerance than the stock English threading. I also did the same to the Stronglight 93 cranks on my Peugeot. For that one I initially sourced some NOS metric Zeus pedals but I just couldn't appreciate the bike with those. If it doesnt use my spd pedals and shoes I wouldn't end up riding it.

Narhay 05-03-20 04:57 PM

https://i.imgur.com/vFbYyBc.jpg

52 40 chainring combination cleaned up and polished.

Narhay 05-10-20 03:38 PM

Waiting on a new headset to borrow the crown race. Otherwise moving along.

https://i.imgur.com/17G6dz9.jpg

https://i.imgur.com/hFqtfg1.jpg

https://i.imgur.com/iwmilYd.jpg

https://i.imgur.com/3HjyQ6s.jpg

https://i.imgur.com/UL4cHD7.jpg

https://i.imgur.com/SWPPOAI.jpg

mikestr 05-11-20 08:30 PM

Wow, this is great. I'm a bit surprised to see a completely painted fork and rear triangle on a Model 300 of this vintage. All those I've seen, including mine, are half-chromed. Given the quality of that plating I wish mine were painted as well. Does anyone have any version info that would indicate when the chroming was begun or discontinued? Was there perhaps a difference in finish between bikes exported to different markets?

I'm unfamiliar with the etiquette here. Would it be appropriate to add pictures of my own Mercier 300 restoration? What I received and the choices I made were different and might add useful information, but I don't want to hijack.

Thanks

Narhay 05-11-20 08:45 PM


Originally Posted by mikestr (Post 21469696)
Wow, this is great. I'm a bit surprised to see a completely painted fork and rear triangle on a Model 300 of this vintage. All those I've seen, including mine, are half-chromed. Given the quality of that plating I wish mine were painted as well. Does anyone have any version info that would indicate when the chroming was begun or discontinued? Was there perhaps a difference in finish between bikes exported to different markets?

I'm unfamiliar with the etiquette here. Would it be appropriate to add pictures of my own Mercier 300 restoration? What I received and the choices I made were different and might add useful information, but I don't want to hijack.

Thanks

Thanks for the comments. I dont have much to add in how chrome socks and half stays were determined. All my other bikes have chrome so this is a bit of a departure for me.

Post your bike here... I'd love to see it.

mikestr 05-11-20 08:56 PM

I will need to add the detail shots--coming soon. But just a quick comment on Juvela's concern about tapping the cranks. There is ample "meat" around the hole, and the amount of metal removed so slight that it's a nonissue. I retapped a 93 back in the mid-80s; it was an accepted and common practice then, and I was strong enough to worry if there had been any cause for concern.

Almost OT and blatantly self-serving, but does anybody need a NOS 93 left arm, 165mm, BSA threading? Talk about an orphan part!

Narhay 05-11-20 09:13 PM


Originally Posted by mikestr (Post 21469735)
I will need to add the detail shots--coming soon. But just a quick comment on Juvela's concern about tapping the cranks. There is ample "meat" around the hole, and the amount of metal removed so slight that it's a nonissue. I retapped a 93 back in the mid-80s; it was an accepted and common practice then, and I was strong enough to worry if there had been any cause for concern.

Almost OT and blatantly self-serving, but does anybody need a NOS 93 left arm, 165mm, BSA threading? Talk about an orphan part!

I tapped them because I am ok with what I did but I understand juvela has a pretty good knowledge of french bikes and the first generation 93s did have some cracking at the pedal hole so I appreciate him weighing in. Subsequent versions were beefed up a bit in this area to address the issue.

mikestr 05-11-20 10:06 PM

I understand, and I would be loathe to question Juvela's knowledge of these bikes, which is undoubtedly much superior to my own. Cranks did and do fail around the pedal hole owing to stress risers caused by defects in the forging and/or fretting on the face where the pedal spindle shoulder bears down and moves over time--especially when not over-designed with extra thickness (apparently an oversight in the early 93 arms). But I think that rethreading alone is not a cause of breakage, as it doesn't (or shouldn't) add any new stress risers and removes perhaps 1% of the total thickness of the crank arm--it's a mere wisp of a shaving that comes out with the tap--the two different pitches are very close, after all. That being said, any old cranks, stems, bars (and frames) should always be viewed with suspicion, as should any bike that has been raced--like mine. I've not retapped the crank on my Mercier, but not for any safety reason.

OK, I'll get the pictures and narrative together.

mikestr 05-11-20 10:55 PM

Another Mercier 300
 
OK, I've located some pictures, and I can add more later. Here's the background and the story. I fell in with French bikes during college, either late '74 or early '75, when these bikes were almost current models. My first good ride was a LeJeune Professional, a parallel model to the Mercier discussed herein, and to the PX-10, Gitane TDF, etc. Had a TA 3-pin crank but otherwise was the same deal--Simplex Criterium, Philippe bars, Lyotard pedals, Mafac Racers, etc. Later installed a Stronglight 93 and other changes, so I still had some extra parts 30+ years later. I loved that bike and rode it everywhere. Sweet ride like most of these French bikes. Replaced it with a new '85 PX, which I still have. I also have a '83 PX-10 "Super Competition"--my first restoration.

About ten years ago I was hanging out in my neighbor's studio and noticed a box in the corner containing a rusty bike in pieces. I then spotted the 93 crank and 531 decals on the form and down tube. My neighbor was small and so was the bike, but I offered to put it back in working shape for her--just hated seeing it turn to junk. She demurred. I occasionally bugged her about it and finally offered ti buy it, as she was clearly not going to use it. Each time she declined. Another two years later, after she'd moved away, I got an email: "I am ready to let go of the bike." She brought it by, took my money, and said goodbye to both of us. Below you can see what I received. It was already cleaned up a bit in this picture, rust removed and paint prep started, but you get the idea.

https://cimg3.ibsrv.net/gimg/bikefor...b447d83432.jpg

https://cimg0.ibsrv.net/gimg/bikefor...6e0dde7b93.jpg

https://cimg3.ibsrv.net/gimg/bikefor...63c443d692.jpg

https://cimg6.ibsrv.net/gimg/bikefor...bd9268523a.jpg

https://cimg0.ibsrv.net/gimg/bikefor...015cd7bf2b.jpg

https://cimg2.ibsrv.net/gimg/bikefor...77f8d2cb1d.jpg

https://cimg4.ibsrv.net/gimg/bikefor...5a12ac4b1d.jpg


https://cimg1.ibsrv.net/gimg/bikefor...a4d52e624b.jpg

https://cimg3.ibsrv.net/gimg/bikefor...7362d837ac.jpg

mikestr 05-11-20 11:23 PM

The story I was told was that this bike had belonged to a youngster in NYC, whose dad owned a bike shop. The boy raced the Mercier in junior events. It made sense: The wheels were a serious pair: Campy Record HF hubs, Rims were Fiamme Red Label rear, Yellow Label (Later called the "Ergal") in front. This is a very light rim--around 280 g. Spokes are butted. Simplex bar-end shifters were another contemporaneous "trick" upgrade. You can see the "demultiplier" unit used with these shifters--very tricky to adjust. Freewheel is the much-respected Regina Oro GS, grungy but with very little wear. The saddle was a Brooks B15, very uncomfortable. So I basically wanted to keep as much of this period-authentic stuff as possible and replace only those components that got in the way of a good fit and safety, as well as the usual wear parts: chain, brake pads, cables and housings, bar tape. The bars were much too small and had to go, as did the treacherous-looking (and too-short) Belri stem. I wanted nicer pedals than the Lyotards and some high-quality traditional sewup tires. More to come.

Narhay 05-12-20 04:38 AM


Originally Posted by mikestr (Post 21469893)
The story I was told was that this bike had belonged to a youngster in NYC, whose dad owned a bike shop. The boy raced the Mercier in junior events. It made sense: The wheels were a serious pair: Campy Record HF hubs, Rims were Fiamme Red Label rear, Yellow Label (Later called the "Ergal") in front. This is a very light rim--around 280 g. Spokes are butted. Simplex bar-end shifters were another contemporaneous "trick" upgrade. You can see the "demultiplier" unit used with these shifters--very tricky to adjust. Freewheel is the much-respected Regina Oro GS, grungy but with very little wear. The saddle was a Brooks B15, very uncomfortable. So I basically wanted to keep as much of this period-authentic stuff as possible and replace only those components that got in the way of a good fit and safety, as well as the usual wear parts: chain, brake pads, cables and housings, bar tape. The bars were much too small and had to go, as did the treacherous-looking (and too-short) Belri stem. I wanted nicer pedals than the Lyotards and some high-quality traditional sewup tires. More to come.

That is a great looking pile of parts. I was wondering what the demultiplier was all about.

mikestr 05-12-20 10:15 AM

I know, crazy, huh? Because this pile was actually a complete bike, I wanted to reassemble it as fully as possible to see what it all added up to, what it had been that had given two owners so much joy. In most cases one gets an old bike already assembled--with non original parts. Then one either finds the best substitutes, looks for the originals--a search that can continue for years--or goes the other way, strips the frame and add to the world's supply of fixies.

The actual name of that part, now that I look t up, is the "demultiplicator." It lowers the ratio between shift lever and derailleur travel. It certainly complicates derailleur adjustment. Anyway, the main goal here was to restore what was rather than to adapt to personal preference (which would be down tube shifters.)

mikestr 05-12-20 10:59 AM

I inventoried and assessed everything. Existing components in good condition:

Brakes: Mafac Racer
Brake hangers-Mafac
Wheels (Campagnolo-Torrington butted spokes, Fiamme rims). One broken spoke.
Freewheel: Regina Oro GS 13-21
Derailleurs: Simplex Criterium
Shifters: Simplex bar-end type with "de-multiplicator" coupling
Headset: Stronglight P2 (replaced locknut with hex-type)
Crankset: Stronglight 93 (chainwheels a bit worn)
Bottom bracket: Stronglight Competition
Cable clips: Simplex
Cable guide: Campagnolo

Frame looked straight, though a slight lateral curvature in the seat tube concerned me. Paint was compromised; rust on top tube and all 4 stays. Also dirty and yellowed. Chrome was quite rusty. I sanded and used oxalic acid immersion where possible. I primed and painted the top tube and rear stays with some high-end enamel I had left over from some equipment repair--happened to match the Mercier. Two-stage clear coat (only on repainted parts). Stabilized the chrome by rust removal and conversion of last bit of rust to black iron oxide, overcoat with clear lacquer to inhibit further rusting--still OK after 7 years.

Cleaned, overhauled all remaining parts. Crank set was in great condition, needed only new chainwheels. Rear derailleur pulleys were disintegrated and replaced with Dura-Ace ball-bearing type from parts bin.

Other parts replaced/upgraded:
Cables and housing: Jagwire
Tires: Veloflex Criterium tubular
Pump bracket, upper: Camagnolo (NOS--not seen in photos)
Toe clips: Christophe (new)
Handlebar: Belleri, 42 cm; Cinelli cork ribbon, black
Stem: Atax, 105 mm
Brake levers: Mafac professional, drilled levers (NOS)
Saddle: Turbo (original c. 1980)
Pedals: Maillard 700 (early model)
Toe Straps: Campagnolo, laminated leather, stainless steel buckles

I'll skip to the last stage. First time doing cabling for bar-end shifters--a different experience:






https://cimg7.ibsrv.net/gimg/bikefor...97210dad17.jpg


All times are GMT -6. The time now is 07:50 PM.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.