DoubleClanger

I am reposting as the very useful web address was wrong in the original post. It is correct below.

I have a Holdsworth 1968 Mistral(?) In the sales catalogue it says that it had a Campag Single Chain ring with the option of a Double. At the moment the bike has a single Silstar 165mm crank arm. However it does have 2 bar end changers installed but no connected. A down tube changer was used. I want to change it back to Campag Double Chain Ring and have bought a Record Strada 175mm 1975 <5> 52T-42T chainring chainset. I need to get a Campag BB but am utterly confused as to what I need. Below follows some of the pointers I have researched



https://www.minortriad.com/campagbb.html



"I expect you will need 115.5mm overall length of axle, probably stamped 68-SS-120. Camp altered RH crank clearance and lengthened axle by 1.5mm in 1978 so if you get shorter axle, you may be pushed for clearance of inner ring? Depends on how much 'fluting' in chainstay. ( I have no fluting as far as I can see) .Your cranks are stamped <6>? You might be OK with 114mm axle. (The ones you sent me are <5> so 1975 - my words )

BUT there are two types of Camp BB cup = thin wall just usual thickness face. OR thick wall which have a water repelling helical 'thread' in axle hole.

Thin wall axles have wider apart bearing shoulders 55mm measured between very tops of bearing radii. Thick wall are 50mm, quoting both sizes from memory!!

So if you fit thin cups with axle for thick, LH cup will go all way in frame and no thread left for lockring.

Other way round and LH cup will stick out too far. Camp helpfully (not) stamped all axles with same number of that era for British frames.

You need BSC cups stamped 1.370x24." English thread.



SO l think I might need a Campag BB 68-SS-120 115.5mm ,either Thin Cups and Thin Spindle or Thick Cups and Thick spindle, the later being preferable for water tightness. BSC cups stamped 1.370x24. English thread.

I am getting very discouraged as what I thought would be a reasonably easy restoration has turned into a nightmare. Am I better selling the crankset and buying a matching pair BB/Crankset?

Can anyone tell me a) which one I need, and b) anywhere that I might possibly get one?

Many thanks in advance for all the help I know will come flooding in. I just hope I can find the threads. I seem to have trouble with that which is why you might have found this before. DC

SJX426 

DoubleClanger I share your pain. Can't answer your question on length. IIRC about 112 or so should work. It is far easier to find thick wall cups than thin. Same with the spindle. Ebay may be your friend if one doesn't show up here. I was looking for a 109 and found it only to find out it needed thin wall cups. I only have the adjustable side which was given to me and still need a fixed side.
Chain line is the objective.
IIRC Campy changed the length due to "safety" requirements around that time period. The 113 makes sense as then moved the crank out 1 mm to accommodate the lip they had to add to the FD.
The reason I responded was to let you know you should seek a solution with thick cups as they are more prevalent. Full BB assembly would be best.

See my quest and saga here: https://www.bikeforums.net/classic-v...nsistancy.html

3alarmer 

.
...are you absolutely dead set on an old school, cup and cone bottom bracket mechanism ? Because the whole issue becomes much simpler (virtually trivial) if you install a sealed unit in the BB shell. And nobody but you will ever see enough of it to know that it's there. With a sealed unit, all you need to know is that it's English threading (stndard), and the spindle length required for your double crank.

There are some minor points about the taper of the spindle ends, and how they fit your crank (in terms of positioning). But They've been covered in many other threads.

Try searching the forum using Google and "Bike Forums" as a limiter term.

romperrr 

I can't help either besides wishing you good luck. These idiosyncrasies make vintage bikes interesting AND infuriating

jeirvine 

For a 1975 Strada crank on an English frame, you need a 112mm spindle. As long as you match the spindle and cups, you can use either thick or thin cup varieties. I have a complete thick-cup one if you need it. PM me.

jeirvine 

That's the one you need.

Last ride 76 

and I have a thin cup set...

SurferRosa

I have thin, Italian cups. No spindle. PM me if needed.

DoubleClanger

Very many thanks for that. Every bit helps to complete the picture DC

DoubleClanger

Very many thanks for reply - I am 72, as I said, so I am a bit old school but not painfully so. Proper job would be better -and more satisfying - but I am not averse to thinking about a sealed unit, IF I knew what it was and how I would install it!! That's the trouble with living in the past.! Stuck in time! Computers are the same!
I am in the UK. Does this change things? Other than physically trying the spindle, I would not know how long a spindle I would need - the crux of my post really - and if the taper fits etc. Very many thanks once again. DC

JohnDThompson 

First, what Campagnolo crank do you intend to use? That will determine the bottom bracket you need. The thick/thin cup distinction only affects the spacing between the race shoulders on the axle. As long as you match up cups with axle it will work. The big distinction with the arms is whether yours are pre-CSPC or post-CSPC. That will determine the axle length for a given ring configuration. Once you know the axle length, make sure you get cups to match the axle (thick versus thin). A 1975 arm will be pre-CSPC, so you'll want the axle to match that arm (68 SS 120), and the cups (thick Nuovo Record or thin Record) to match the axle style you have. If you're lucky, you will be able to source axle and cups as a matched set.

3alarmer 

...gee whiz, I'm 71. It's not like these sealed cartridge BB replacement units haven't been around for a while. You probably just have more of a life than me.

Anyway, here's what they look like, but you'll need to answer JohnDThompson 's question on the details of your particular Campagnolo crank in terms of what length you need. apart from that, your bicycle has standard threading in the BB, so if you go this way, order that one. Also, if you want to use one, you'll need to add another tool to your collection (they are pretty cheap.)




...these days, it's usually easier to source this stuff on the internet, like on Amazon or Ebay.

DoubleClanger

Hi 3a,
Thank you so much for that. Very helpful information. Distinctly a possible way to to take the anxiety of trying to get an original.
Does the sealed unit have to be a Campag unit specifically?
I have been out of touch for 60 years so I need to catch up!
If you have time could you help me ....How do you get a photo in the message as you have done? As I said before,... Yes, I'm 60 years behind on IT too - if that is possible!!
Thank you again from the UK.
Stay well in these difficult times. DC

SJX426 

DoubleClanger No it does not need to be a Campag unit. BUT, the issue of taper is now the question, JIS vs ISO. Campag is ISO and Japanese products are typically JIS. You can mix. see Sheldon Brown.

Photos can be added by clicking on the picture icon next the smiley face above the response text. Choice is from a host like Flickr or other internet picture application/host or your PC. I am only a couple of years younger and I don't recall IT being a term in my youth, 60 years ago! One of my professors in college helped invent the transistor at UNIVAC back in the Late 40's. The use of electronic computers with IC's and processors for the public came about in 1964. Believe me, it is a lot easier now than when I was in college! Programing was done by punching holes in heavy paper stock and waiting a day for results, good or failure to compute!

BTW: if you want to get someone's attention, like I did you, type @ in front of their user ID (name). A list will show up as you type. When you see it click on it.

DoubleClanger

Very many thanks for the info on Campag and also how to include a photo. I am getting there slowly!! I have just accidentally found out, by a careless slip of the finger, how to send a PM.
I am in the UK and wish the very best of health in this dangerous time.
Cheers from England DC