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Post by eaglerock on Mar 28, 2018 0:08:12 GMT
I've been working in fits and starts on assembling my 1973-ish filleted Lambert Professional Grand Prix 24K, and the front derailleur situation has been a real headache. I don't have either original derailleur, but the photos I've seen of the OEM Lambert FD look like a cable-operated pillbox system, similar to the 50s-60s Campagnolo Gran Sport/Valentino, or the Simplex Prestige. The key problem is the front cable router, which directs the cable to the non-driveside of the seat tube, without the rightward angle of most braze-on and clip-on routers. Most road front derailleurs clamp the cable on the driveside of the seat tube; using such a derailleur wraps the cable tightly against the back of the tube. In a conflict between rubbing steel cable and soft gold plate, guess which one is going to win? My first attempt was with a Campagnolo Nuovo Record, which demonstrates the router and the resulting cable wrap problem: The next thing I tried was a pillbox Campagnolo Gran Sport, whose pushrod is far too short to get to all three chainrings. Next, I started looking for normal parallelogram derailleurs that clamped on the non-driveside. There are several Suntour variations (Spirt, Compe-V, SL/NSL) and several Huret variations (Allvit, 700, Challenger, Club, Club II, Success) all of which clamp the cable to the left/non-driveside of the seat tube's centerline. Here's the rear of a Suntour Compe-V, to demonstrate the geometry: The difficulties with the Suntour derailleurs are: 1) they're high-normal, so the untensioned cable puts you in the big chainring - the opposite of normal shifting 2) in order to make the lever action work, there has to be something stiff pushing against the cable stop below the clamp, like a routing cable housing. Which is where I am now. I suspect that a short length of cable housing (shifter or brake) butted up against the derailleur's cable stop will do the job, but what will work at the other end of the housing? I can try to jam the end of the housing into the braze-on cable router, in the hope that it stays in place. But it may slip out when the cable is slack, and it'll look terrible whether it works or not. How do I cover three alpine-geared chainrings without redirecting the front cable router or damaging the gold plating on the seat tube? What other gimmicks have people tried in replacing the stock derailleur? Are there other derailleur models I should look for?
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Post by wheelson on Mar 28, 2018 1:16:24 GMT
I believe you'll find that the Shimano Titlist will work for you. That's what I'm using on my Viscount and while mine is set up as a double, I've used this derailleur for triples many times. My Viscount has your type of braze-on: www.flickr.com/photos/wheelson2011/albums/72157693177987474/with/25655157527/I think there are several photos of the front derailleur. Where are you located? I possibly might have a spare, but I'm in Pennsylvania, USA. Best, John "wheelson"
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Post by eaglerock on Mar 28, 2018 5:17:38 GMT
I believe you'll find that the Shimano Titlist will work for you. That's what I'm using on my Viscount and while mine is set up as a double, I've used this derailleur for triples many times. My Viscount has your type of braze-on: www.flickr.com/photos/wheelson2011/albums/72157693177987474/with/25655157527/I think there are several photos of the front derailleur. Where are you located? I possibly might have a spare, but I'm in Pennsylvania, USA. Best, John "wheelson" I feel like I'm missing something about the mechanics of the Shimano derailleur. As I look at the photo on Velobase, it appears to have the same design as the Suntours (tightening the cable draws the clamp bolt arm down towards the fixed cable stop): But the photo of your bike appears to have a bare cable running from the braze-on router to the derailleur - wait! I get it! With the Suntours, the clamp is fixed and the cable stop is drawn up; with the Shimano, the cable stop is fixed and the clamp is drawn down. With the Titlist, nothing needs to butt against the cable stop, because the stop doesn't need to be pushed anywhere. Is the Titlist also low-normal? Your offer is greatly appreciated, but I'm in Northern California (San Francisco East Bay). Fortunately, that means there are three bike kitchens within five miles of me. At least now, I know what to scour for. Thank you!
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Post by wheelson on May 5, 2018 0:19:10 GMT
Bit of an update. In my photos, I show the large Lambert/Viscount "holey" ring de-toothed as a chain guard. Since I'm taking my Viscount to the Classic Rendezvous Weekend in Greensboro, North Carolina (USA) I decided to make it as conventional looking as possible. I'll post updated photos when I can.
I had previously set this up as a double using 46 and 28 TA rings and 13-32 freewheel, shifted by a Shimano Crane long cage, a Titlist front and standard Shimano downtube shifters. So imagine my joy when, after adding the new-looking "holey" 52t ring, moving the Titlist up a bit, and making a few adjustments, this setup shifted perfectly.
Pretty extreme range for the old Titlist front, if you can find 'em, stock up!
Best, John "wheelson" Wilson Greensburg, PA USA
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vfrman
Viscount
hi-13 lamberts[2 gold, 1 reg harris] 3 10 speeds
Posts: 33
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Post by vfrman on May 5, 2018 3:38:51 GMT
hi out there-having perused ebay for front derailleurs, it appears there are numerous options. clicking on suntour [ebay] first it gives you the option of brazed, clamp-on, etc.. then you can click on bottom pull or top pull. then you also have a choice of double chainring or triple-chainring etc...whew? clicking on campanolo and simplex produced the same results. so the possibilites and options seem endless..having acquired 12 lamberts now [thats another talk show], i havent even examined them all yet thoroughly; i have the luxury of being able to study original lambert, suntour, and simplex parts. former owners also installed various shimano and campy [easier to spell] items as substitutes..the lambert FD has never failed in thousands of miles; the lambert RD that came on newly acquired NOS gold bike looks like a piece of junk as several have suggested?!..may never get a chance to test it unless installed on used gold bike acquired in february or other lambert. the suntour GT seems most prevalent on the other lamberts. which brings up simplex which i'm/we are spotting everywhere. unless we hear from someone or people that worked at the factory, we can only speculate..the used gold bike came with a suntour vista in the rear; the "chrome" lambert on ebay at the moment has a suntour "honor" on the rear-whew!! the "new" lambert/viscount member in australia was not aware 15 speed bikes even existed..it looks now as if the bike makers are designing 2 chainrings that fulfill the needs of 3 chainrings that were made before. i hope this helps, regards, vfrman
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Post by eaglerock on May 8, 2018 2:27:41 GMT
Where I am so far: In searching my local bike kitchens for a 1970s Shimano, the only one I could find with a 28.6 clamp was a Thunderbird - a chromed steel monster that weighs a ton (okay, 185 grams, but it feels like a boat anchor). It was pretty beat up, and pretty rusty; clearance under the low-Q Lambert crankarm was quite difficult. A swap with the list administrator at Classic Rendezvous got me a Huret Success, which is rated for both double and triple chainrings like most of the 1970s Huret front derailleurs. It's a low-normal derailleur like the 1970s Shimanos. Also similar to the Shimanos, the cable stop is fixed, while the cable clamp levers down as tension is increased. The Success is a late-'70s derailleur, so a little out of period; but at 125 grams, it's one of the lightest derailleurs that satisfies the clamping requirements, and the chainring capacity of 27T is a lot more forbearing than the Thunderbird's 16T. The hunt through my parts boxes also unearthed a much lighter 80 gram Huret Jubilee (that I didn't realize I owned), which clamps the cable on the driveside like a more modern derailleur. The Huret Success works in the Lambert triple setup, but you really have to get everything right. The cage has to be almost exactly parallel to the chainring, or the rear bolt starts digging into the back of the crankarm. I've ridden 50.4 cranks for a decade using a Campagnolo Record, and I'd never experienced the crank/front derailleur interference that's a common complaint for those cranks. I guess my luck had to run out eventually. The Success is supposed to have a sort of spring steel at the front of the inner cage, for durability in upshifting. Perhaps I should try angling the front end outward a little, to see if that makes a difference; upshifting does seem to be a bit sluggish.
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Post by 54roadie on May 16, 2018 19:47:16 GMT
Pretty extreme range for the old Titlist front, if you can find 'em, stock up! Best, John "wheelson" Wilson Greensburg, PA USA Hi John, If you care to actually stock up on Shimano derailleurs taken off of Viscounts, I have a complete package - front Thunderbird, rear Titlist, downtube shifters, 5 speed freewheel. I'm in Chicago, so shipping is not exorbitant. Does $35.00 plus postage sound reasonable? The derailleurs, especially the rear, are near mint, and I've seen them for that much on eBay. You'll get the rest of it for free, basically. Just let me know. Best regards, Frank
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