I've been enjoying this thread and though I don't have much. to contribute, I thought I'd share this mess that ended up in my hands. I think it's a Raleigh Grand Prix and although it's a disaster there are all kinds of quirks to it.

Someone has set it up with as a triple with A. Duprat cranks. Unfortunately they don't seem to be anything special (and they are in awful shape), but I found them curious nonetheless. I'd be interested to hear any thoughts any of you have to share that may educate me a bit more about Duprat cranks or this curious setup. The inner ring has to have less than a mm of clearance between it and the stay. Anyone think these are worth cleaning up and installing on a better frame, or at least one without a bent fork?

Cheers.

a great thread with some lovely pics but.......seeing as how the TA crank is the only one to include
pedal washers lends creedence to the long held theory that the arms are soft and flexible. also the
Nervar arms remind me of the Nervar Star which was used on mid-line at best so not the top-line that
I've become so used to. I'm much more enamored of the TA Tevano. I"ll get my low gears with a large
rear cog. Long arm Jubile mechs work just fine.

solida

This setup still needs some finetuning but at least I can upshift to the 48T from the 28T chainring.
Doesn't seem to play nice with the 11-speed chain (48/28T x 11-32 11-speed) but that might just be the spacers between the two chainrings. My bet is that I can get them closer with some stainless steel rings or thinner spacers.

Just like [MENTION=137164]southpawboston[/MENTION] said these can be too narrow for some setups. No issues on my 9-speed triple setup but this 11-speed double is rubbing. Are some of the modern (VO, SunXCD) cranks wider than the classic cranks? It seems like the end of the cranks is rubbing against the chain in the Big/Small combo.
I will shoot some pictures tomorrow of the chain in between the two chainrings.

-----

one o' me favourite five-pin chainwheel patterns are the ones with the "pickles" cutouts

suspect they were produced by more than one manufacturer

does anyone have any hard information on them?

---

here is a Magistroni set exhibiting the "pickles" from the famous Bozzi catalogo di MCML:




[image courtesy of condorino.com]

-----

My 1957 Carlton came to me with these 2nd generation cranks from TA. There was a first generation, very similar but with deeper flutes on the arms. According to VeloBase the 1st generation was introduced in 1962. I'm trying to determine when these 2nd generation cranks were issued.
Do any of you have access to TA catalogs or other catalogs showing TA cranks from 1963 or 1964 that would help establish the date?






Brent

-----

CriticalThought & obrentharris -

for information on the history of frankish chainsets and their makers this thread over at the veloretrocourse forum is simply wonderful

advisory: visitation could create what is known in the UFO community as "missing time" - whole days could go by as one takes in these chainsets...

https://veloretrocourse.proboards.co...95/les-strongs

CriticalThought -

lots of A. Duprat material right on the first page


-----


-----

Got me another set of Stronglight 49D's, this time the older "Depose" version:

-----

chainwheel set cannot be earlier than MCMLXXIII with those allen key fasteners...


-----

Crank arm length question:

Which 50.4 arms are/were available in a 175-180mm length. I've seen a pair of the Sugino Maxy in a 175mm. However, in my ebay searchs all of the available lengths seem to be 167.5-172.5.

I like the SunXCD unit, but it maxes out at 172.5.

I've got a 180 mm steel cottered 5 pin but no matching NDS. I think it's Nicklin.

I may have posted this in another thread, but it fits here too...

-----

'76 was first year for this edition of the NERVAR Star series

it received a cosmetic revision between '75 & '76

all parts interchange between the "Mk.I" & the "Mk.II"

'76 also first year for relaunch of Schwinn Superior model


-----

TA made both. I have owned a pair of TA 180s and currently have a pair of TA 175s mounted on my “gravel” bike.
Brent

Many thanks once again Juvela. I hope google translate will render it accessible to my French feeble faculties.
Brent

If I remember right, the Nervar Star moniker was reserved for the one with the Campy-style 5-arm spider, with the 128 mm BCD.
The 5-pin 50.4 mm cranks didn't get "Star" in the name.

Because I was a racing snob at the time, I thought the Star crank was the only one for Real Men, and I looked down my nose at the 5-pin. But nowadays I would trade my Star cranks for the same thing in the 5-pin style for sure — so much more versatile.

A nice example of a Star:


Mark B

Today in adventures in 11-speed:

I wanted to shoot some more pictures of what you can run into when using these cranks with modern 11-speed gearing.

Now these are modern Spécialités TA Pro 5 chainrings, one of which I still had lying around the other I ordered because I wanted a smaller inner chainring. The cranks were originally a triple and came with the mounting bolts for a triple. So I ordered a bolt set for double chainrings and this is what happened:





Essentially the way the chainrings mount means there is slightly too much room between them and the 11-speed chain can (but not always) drop between them. Damn.

Now for those not familiar with it, all deraileur chain from the past 30-40 years or so fits on "3/32-inch chainrings" but with denser cassettes in the rear the chain has become narrower.

So where 6 to 9-speed chain is all about 7mm (9/32″) wide, modern 11-speed is often 5.5mm (7/32″) wide and newer 12-speed chain is even 5.3mm (13/64″) or even 4.9mm (3/16") for 13-speed Campagnolo.
(and don't get me started on the weird numbers this makes in inches. My first instinct is to convert it all to 18/64", 14/64", 13/64" and 12/64" for ease of comparison.)

Now if you think this means the chain must be getting weaker because it's so thin... think again. Modern 12-speed chain lasts twice as long in testing compared to it's 11-speed counterparts and three times as long as the 9-speed versions.
Then again, it better be. A €90 MSRP chain ($108) versus a Shimano HG95 Ultegra chain that's available for less than €30 ($36) is a big difference in price. Even though the 12-speed last three times longer.
This is all down to modern materials engineering, metal hardening and coating treatments. You could argue we could get similar longevity if they applied that knowledge to 9-speed chain... but AFAIK nobody makes those.


Source: CyclingAbout.com & Zerofrictioncycling.com

Anyway, I'm getting off-track here. So my 11-speed chain is 1.5mm narrower than the chainrings were designed for so it drops inbetween. So how thick are those spacers? As it turns out; 3.6mm.
It doesn't help that they are a weird ø12mm x 7.15mm x 3.6mm size.

I mean I can easily find -a2/din-125a-[-]-a2-[-]-m6]M6 rings, which are 12mm x 6.4mm and a 7.1mm drill bit but if two of those stacked are 3.2mm it doesn't make a lot of difference.
Perhaps the easiest way is to simply sand down the aluminum spacer rings to a thickness just over 2.1mm and see what that does. The ones I got are from Velo Orange so if I mess up they aren't that expensive and offer bigger 10mm stainless steel bolts.

Expect an update in the future.

When I assembled my triple, I found my triple bolts had 6 spacers that were 3.51-3.54 mm thick and 6 spacers that were 2.7-2.8 mm or so (should have written the number down). Check your spacers - if you've got narrower spacers, and 0.8 mm narrower spacing will help your shifting, you may already have a solution.

(The above comes from this thread: TA Cyclotouriste triple assembly question.)

If you like I can make you a set of six 2.1mm (have a lathe) - and if they don't work you still have the thick ones.

Here’s a half-step/granny on my Paramount. With a 14-32 5 speed on the back it’s a perfect setup for hilly Seattle.

Hi Jacco, I'm sure thinner spacers can be found to accommodate for the thinner 11 speed chain. The front shifting will suffer from the lack of ramps and pins on the rings.

Reid

I’ve also got a “compact” 48/36 setup on my Hetchins. Not super high or low but it’s a good rider.

That would be great. I'll send you a PM.

Yeah I figured as much. I have a triple where the 26T innner shifts into the 42T middle ring and that can be slow at times but I attribute that to the low chain tension. I can always throw on a smaller outer ring. Maybe even one of the pinned and ramped ones by Velo Orange.

I do know a 20T difference is a lot. Most derailleurs have a maximum of 16T. But I do believe a better shaped cage might help here. A 2x11 Shimano Ultegra FD-R8000 has a narrower and more shaped cage with some extra guides on the inside. I could drop down to a 44/28T and still have a fairly good gear range of 457% or 24.3 to 111 gear inches.

did something similar but he uses a 46/30T chainring so it's within spec.

Pins and ramps really do come in handy when you use 10 speed chain and up.
I have a Pro 5 Vis with a SunXCD spider and a triple ring ring setup on a Jack Taylor Tandem. It worked perfectly with 9 speed chain. Upgrading to 10 speed and it didn't shift properly at all. I had to replace the middle ring with the appropriate ramped and pinned ring for middle position use and then things were fine.

Similar situal with a Rene Herse crank running a 46/30 without ramps and pins. Were slow unpredictable shifts. WIth the ramped and pinned 46T ring installed, it shifted instantaneously.

Reid