Holdsworth Cronometro Ultralight now finished with pics

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The next instalment soon, but first I must thank Nob for the images of Cotters and French on their steeds. There are a couple of links showing the same frame in the Faema white and Red colours here; https://www.flickr.com/photos/40402003@ ... 269594110/
and the complete bike here; https://commons.wikimedia.org/wiki/File ... 202%29.jpg
Whist watching Alf “The King” DVD, I noticed that a young Sean Yates also rode one.

I enjoyed reading bduc61 thread and the very nice build.

So off we go, I earmarked a Campag Super Record Pista Chain set with a 54 tooth chain ring and after a little sweat I drilled the chain ring to save the odd gram. (Weight 544g inc bolts)



A Super Record Titanium BB was fitted, but alas was too long and the chain line would be wrong, a shorter Super Record (257g) sorted the Chain line out, but was heavier. Bummer, I could have saved 70g.

The wheels, large flange was all the rage at that time and the only pair I have are 28hole Suntour Suberbe large flange hubs laced to Mavic CX18 rims with some early aero spokes, weighing in at 699g front and 769g rear, without skewers. Another search in the spares bin, I found an old FT skewer and a Roval skewer that were much lighter than the original Suntours, (122g).




A great saving on weight can be made with the tubular and these Clement Clementex come in at 335g for the pair. If anyone know anything about these please let me know.




Following a previous build I had freed up a 1st generation Super Record rear mech (187g) and this would have been my choice if I had not decided on the weight weenie option, I remembered that I had a Huret Jubilee sitting in the drawer (150g), this would save me a further 37g, However the Huret lever (31g) was rejected in favour of a drilled and lighter Campagnolo unit (20g), another saving of 11g.



We pushed some big gears in those days and with a 54 chain ring and Suntour Alpha block13/14/15/16/17 (288g), will result in a range of 112” to 85”, perhaps a little too big for me now.

I will add the all the presure points next along with a list of parts and total weight later and finished photos.

In the mean time I found this article in a 1978 Cycling comic, somehow the numbers don't add up!
 

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Re:

57 ring was the standard of the top guys like Cotters, Engers, Adkins, Queen. Pyne & Cammish used 56 rings & all had 12-17 blocks.

Nice 54 ring but I'd still the holes bigger. You could use an OMAS Ti BB as that was the choice of the day.

Huret nice choice & drill out the jockey cages. Use the milled out Campag lever. Get a Maillard dural alloy block if weight weenie is name of the game.
 
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Yes, it would be desirable to have a 57 tooth chain ring, but this one will have to do. I will see if the drilling of the 54 tooth can be made larger, Nob, what size holes do you advise?

Unfortunately, I have used the Omas BB on the Chesini Precision and finding a good Maillard Dural alloy block is going to be like looking for hens teeth. I will keep an eye open.

There will be many parts that are lighter but at a cost and availability could be a problem. I have a titanium front axle that could be fitted and a good rear FT hub, these could save a few grams and I will estimate how much weight saving can be made after I have completed the build. I am sure that I won’t have all the lightest parts money could buy or modify, but it is fun playing with what you have got available.

All comments welcome, the build so far.
 

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Re: Holdsworth Cronometro Ultralight

That is looking really good, 70s stuff never disappoints. I'd like to have a go at drilling a chainring, any tips?
 
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Boscarn":1wbuc773 said:
Yes, it would be desirable to have a 57 tooth chain ring, but this one will have to do. I will see if the drilling of the 54 tooth can be made larger, Nob, what size holes do you advise?

Unfortunately, I have used the Omas BB on the Chesini Precision and finding a good Maillard Dural alloy block is going to be like looking for hens teeth. I will keep an eye open.

There will be many parts that are lighter but at a cost and availability could be a problem. I have a titanium front axle that could be fitted and a good rear FT hub, these could save a few grams and I will estimate how much weight saving can be made after I have completed the build. I am sure that I won’t have all the lightest parts money could buy or modify, but it is fun playing with what you have got available.

All comments welcome, the build so far.

Its all looking good so far 8)
FT Hubs are great but small flange & rare to find as OMAS Bologna Hubs are a more easy find.

Everest Gold slotted chain has to be a good option :?:

Campagnolo Super Record Pista Pedals :?:

As for drilling here is my 54 ring & I think I used a 5/16" drill maybe 1/4" on your ring.


This ring has since been replaced with a 57 ring :)
 
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Andymart, For drilling the chain ring, I did cheat and used an old 54 chain ring that had been drilled as a template, then fixed them together on a piece of MDF and using the old ring holes to drill through.

Nob, I have just measured the drilling and when fixing the two rings together they were not exactly the same and the alignment of the holes are not centred perfectly as a result I only have 1.8mm of ring left on the inside edge. Making the holes larger may show this error up and weaken the ring? Food for thought.

A never ending supply of Everset Special Oro chains would be nice, once again the only one I have has been used on the Chesini along with the 3TTT Superleggero bars and I am reluctant to remove the at the moment. However the Super record pedals will be reused in this build.

The FT rear hub is presently laced to a Mavic SSC rim, the nickel plate is peeling off the hub. I have a replacement hub shell and will rebuild it one day. Interestingly, this wheel weighs the same as the Suntour/Mavic CX18, both are 28hole so the extra SSC rim weight must be the same as the lighter FT hub.
 
Re: Holdsworth Cronometro Ultralight

if that's the case that's a shame as the holes should be bigger. 24/24 wheels would be the goal if weight is the goal. but keep your CX-18 if there is no alternative but on a build like this nicely polish super champion rims with dugast piste diamond silks is an option similar to my roger queen build.
 
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As the weather has been awful this week, I spent some time polishing parts for this build and found time to rebuild the FT hub and remove a spare CX18 rim from an old wheel.

The new wheel was expected to be much lighter on paper, the CX18 rim should be much lighter that the Mavic SSC, however the new wheel weighed in at a disappointing 758g, this is only 12g lighter than the planned wheel. The SSC rim was much lighter than the info on Velobase and the CX18 a little heavier.




The bars to be used are 3TTT Competizione (300g) and I have a choice of stems, if the 115mm SR Ultralight (187g) is too short the 140mm Cinelli with the alloy stem bolt (308g) will be fitted. I will tape the bars with classic cloth tape from the brake levers down (I may dress the brake levers as I do like to use them for riding when not racing) and use an old wine cork to finish them off.



A matching SR ultralight seat post (216g) is preferred over the Campag SR (252g) and the ITM Aereo (22mm) with sleeve to fit 27.2mm (242g). I did try to use the titanium fitting from the SR on the Campag to see if any weight could be saved, but alas they did not fit..



A Saba Record (234g) saddle will complete the perch.



I have already removed the pedals from the Chesini and replaced the toe clips with some Ale alloy ones, I hope to soon receive a pair if Christophe alloy that may be lighter. The straps are unknow to me,(they came with a old pair of Italian toe clips that had been painted) they are nylon with a nylon clasp that allows for tightness adjustment. (314g)



So everything has been chosen cleaned and is awaiting final assembly and weigh in, hopefully the weather will be better tomorrow for some pictures of the build.
 

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