kroozer 

Somebody is offering NOS Stronglight 3-pin 116mm bcd 38-tooth chainrings on Ebay for $20 shipped. These will fit many vintage cranks, I bought mine for a TA Professional. These are great cranks but it is really hard to find chainrings for them that are smaller than 42t. I have not yet received it and am not sure if the holes are the correct size, but that's something I can work out.

bikemig 

Just bought one.

juvela

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thanks for this great tip!

assume they would be TS

are they offering both regular & bis or just regular?



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nlerner

I took a flyer one one, but I’m guessing that those holes will need to be modified if used for a TA 3-pin crankarm. They look like they were designed for Stronglight 116 bcd cottered steel arms.

https://www.ebay.com/itm/275603608415

bikemig 

What's the difference between the Stronglight 116 bcd chainring and the TA and how does this need to be modded to work?

repechage

From the image, bores need to be enlarged and if one had access to a mill, a counterbore added, verify you have 2mm gap to the chainstay to avoid that need.
‘there might be a need to file the ring to clear the TA pro lands.

52telecaster

Do you guys think these are aluminum?

oneclick 

Thanks, got a pair.

I have a similar 36 tooth, just went and checked, the holes are about 7.25mm dia and the TA arms just fit nice and snug.

For this - and any other inner ring - don't bother to counterbore, just use a longer sleeve.

nlerner

As others have pointed out, different sized chainring bolts. The TA 3-pin also uses bolts unique to that chainset; different size from anything else I’ve seen. The Stronglight steel cottered (and its Nervar variant) don’t use a bolt and sleeve system, but just a bolt as the crankarms are threaded. That’s what these rings are intended for, I’d guess.

oneclick 

I think rather that they are for use with a Stronglght TS or TS bis (aluminium square-taper) cranks - though of course the BCD is the same.

nlerner

I actually have a TS DS arm hanging on the wall. I’ll try that ring when it arrives.

mpetry912 

timebehindbars is a good ebay seller

/markp

nlerner

My ring arrived today, prompt shipping from PA to MA:




As I guessed, those small holes don’t quite line up with any of the 116bcd cranksets I have around. Here it is on a Stronglight 3-pin of some sort:


You can see the holes on the crankarm have a larger diameter than the holes on the ring:


Here it is next to a 42t ring for a TA 3-pin crank arm; again holes are smaller:


I also tried it with a steel cottered Stronglight arm, which uses threaded crank bolts through the ring and into the arm. The problem here is that the arm has a raised ridge around each hole. Mind the gap!


So to be useful, I’ll need to enlarge the holes on this ring. Might have to finally figure out how to use the drill press I traded a vacuum cleaner for.

juvela

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thank you for this information

​​​​​​

the chainset model in your image is Verot's TS which stands for Touring Sport

IIRC it launched in 1974



note how in this parts illustration the chainwheel you received appears to match the part number 252 in the drawing

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nlerner

I thought it might be, but I feel like I’ve seen a version that has TS engraved on the arm? Maybe I’m imagining that.

juvela

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yes, there is early and late

the revision may have occurred with the big reworking of the range which took place for the 1977 model year

this is when:

model 93 was discontinued

model 99 was revised

model 104 was launched

model 105 was launched


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nlerner

Ah, Velobase.com abides, as always:

https://velobase.com/ViewComponent.a...=115&AbsPos=71

Not sure how I ended up with one DS arm, but it does reasonably match a later model 99 NDS arm.

juvela

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another variable to be aware of for readers -

lands thickness

up until the launch of models TS & 99 Verot's chainwheels were always tooth cut from one side of the stock only

when assembled into a chainset they were mounted with the flat sides facing each other

this means that the thickness of the lands ("spacer") is thicker on a model 57, 63 or 93 than it is on models TS, 99, 104 and 105

models TS, 99, 104 & 105 all have their chainwheel teeth cut from both sides of the stock so their lands need to be thinner to have the correct spacing between chainwheels


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oneclick 

a) that lip on the steel arm is good engineering; it means that the chainring bolts take no shear stress; and
b) don't drill those holes 10mm, there isn't enough left after; instead just bump them to 8 and use the crank bolts reversed, as indicated.

kroozer 

I just received my chainring and promptly lined it up and drilled and filed the holes to match the TA cranks. I think there is still plenty of metal around the holes, but we'll see.

Paul Waque 

Th
Chain on 52 and 28 in the rear.

Chain on 38 in the front and 14 on the freewheel.
​​​​​​The next cog up had better tension. Pretty good for that little Jubilee derailleur.