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Old Bicycle Parts

jorglueke

Iron
Registered Member
#1
Hi, I am new here driven primarily by my hobby of restoring older bicycles. I am not at present a machinist though I have an interest. I've dabbled in metal working in the past as well but time, and children, and money are all factors as well. Anyway, on to my specific question.

I've come across a cup and cone bottom bracket for a 70mm shell. This is from the 1970's and not normally an issue as the Italian standard was 70mm shells. But the threading on these cups is English. English threaded cups use a 68mm shell so there's one mismatch. The other one is that the spindle is tapered 3 degrees instead of the standard 2 degrees. The best option is probably to find the pieces in better shape than mine, another option is to try and use a modern sealed cartridge which according to some should work but then I can't use the original crank. My question here is how hard is it to machine pieces like this, can they be repaired? The races for the bearings on the moving cup are a bit worn.

I hope this question makes sense.



 

markba633csi

Active Member
Active Member
#2
They would be darn hard to machine. You could anneal them, machine them, and then re-temper them but the effort would not be worth it.
That's my opinion though. It IS possible.
Mark S.
 

jorglueke

Iron
Registered Member
#3
Thank you, that is good to know. Is it the threads that make it difficult, the somewhat complex shape or something else? I will look around here at some beginner projects to get an idea of what is simpler to do.
 

Wreck™Wreck

Active User
H-M Supporter-Premium
#4
The threads are the easy feature, hardening then grinding the races (if ground in the first place, it is after all a bicycle not an aircraft) will prove more difficult in the hobby shop.

The major question is, once again, how many parts?
 

Uglydog

Active User
H-M Supporter-Premium
#5
I wouldn't suggest you alter a vintage crank.
However, depending on the crank design, you might be able to cold grind the ends of a sealed bottom bracket to fit.
I'm near Anoka MN if you want to work on it.
What level of quality (tolerance) do you need?
If this is a rusty enthusiast ride then all you need to do is get it to fit.
If you are working on a classic restoration then we need to up the expectations!

Daryl
MN
 
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woodchucker

Active Member
Active Member
#6
I wouldn't suggest you alter a vintage crank.
However, depending on the cranks, you might be able to cold grind the ends of a sealed bottom bracket to fit.
I'm near Anoka MN if you want to work on it.
What level of quality (tolerance) do you need?
If this is an rusty enthusiast ride then all you need to do is get it to fit.
If you are working on a classic restoration then we need to up the expectations!

Daryl
MN
way to go Daryl, I see you volunteering a few times since I have been on here. A big thumbs up..
 

jorglueke

Iron
Registered Member
#7
The threads are the easy feature, hardening then grinding the races (if ground in the first place, it is after all a bicycle not an aircraft) will prove more difficult in the hobby shop.

The major question is, once again, how many parts?
I don't know if anything is ground. In the pic you can see the wear from the bearings towards the bottom of the cups. I think they just sit in the lip of the cup and then the flared out part of the axel sits right on top and keeps them in place. Grease every 6-12 months and you're good to go until they wear out.
 

jorglueke

Iron
Registered Member
#8
I wouldn't suggest you alter a vintage crank.
However, depending on the crank design, you might be able to cold grind the ends of a sealed bottom bracket to fit.
I'm near Anoka MN if you want to work on it.
What level of quality (tolerance) do you need?
If this is a rusty enthusiast ride then all you need to do is get it to fit.
If you are working on a classic restoration then we need to up the expectations!

Daryl
MN
Thanks Daryl. I am of both minds on this, I'd like to ride it restores with the original crank since it is alloy but also it would be fun to try with a cartridge. The latter would cost more as then one needs a new crank as well. The frame isn't rusty except for a few small spots I've treated. I want to get this running because it's a different type of steel and a large bike. If I really liked it I would probably give it a paint job or try to luck out and find a better frame in this size.

As for the grinding the bottom bracket I think that shouldn't be necessary. I have a little difficulty visualizing whether a 68mm or 73mm would be better but because tyhe cartridge's sit flush on the drive side they shouldn't need grinding, the non drive side might just thread in a bit deeper.

But I have some much older projects waiting.
 

jorglueke

Iron
Registered Member
#12
No, they used to use them to hold the cranks in. If you google cotter pin press tool you'll see the one's park tool use to make and also pics of homemade ones, using mainly a grinding tool.
 

whitmore

Active Member
Active Member
#14
I've come across a cup and cone bottom bracket for a 70mm shell. ... The best option is probably to find the pieces in better shape than mine, another option is to try and use a modern sealed cartridge which according to some should work but then I can't use the original crank. My question here is how hard is it to machine pieces like this, can they be repaired? The races for the bearings on the moving cup are a bit worn.
It's hard to make a good ball bearing race, and the wear you see on yours is probably enough
to make it irreparable. Once I machined a replacement cone, but it wasn't the right alloy,
or wasn't hardened, or wasn't the right shape... and it disintegrated. For a good ride,
though, you don't need to let someone ELSE build the sealed cartridge, it ought to be
possible to create your own design, and thread it to mate with the existing frame, using
ball bearings (sealed is probably best) from a number of sources (eBay, vxb.com, etc.).

Easiest is to buy ALL replacement parts (one ought not re-use worn shaft or cup,
and the balls are SO inexpensive it's hardly worth inspecting the old ones).
If you machine for fun, a shaft with cotterless ends would be a fine project
piece, and some threaded fitting parts that mate with commercial ball bearings
will get you the benefits of an expensive cartridge, plus swarf!

Use a good tough steel for the crank; I've broken a few (Ashtabula type), it's not
an optimal biking experience. Bent wouldn't be better.
 

Uglydog

Active User
H-M Supporter-Premium
#15
If he makes the trip (likely multiple) to my shop, it will be my intent to help him make his own part.
I'd expect him to contribute some cash to cover basic shop expenses.
I'm on my own learning curve and don't pretend to have the answers. However, I'm willing to give what I believe I know.
Yes, attempting to make those races is a bad plan for the reasons you cite.

Daryl
MN
 

Mark Stonich

H-M Supporter - Premium Content
H-M Supporter-Premium
#16
I've come across a cup and cone bottom bracket for a 70mm shell. This is from the 1970's and not normally an issue as the Italian standard was 70mm shells. But the threading on these cups is English. English threaded cups use a 68mm shell so there's one mismatch. The other one is that the spindle is tapered 3 degrees instead of the standard 2 degrees. The best option is probably to find the pieces in better shape than mine, another option is to try and use a modern sealed cartridge which according to some should work but then I can't use the original crank. My question here is how hard is it to machine pieces like this, can they be repaired? The races for the bearings on the moving cup are a bit worn.
70mm shells were quite common on Raleighs and other brands owned by Raleigh. 70mm shells were usually 26tpi instead of the usual 24tpi. What bike and crank do you have? I'm into vintage steel bikes, and my entire business is based on cranks. Yet I'd never heard of a 3º taper. But checking my 1980 edition of Sutherlands, I see that some Asian spindles were made for 70mm shells and with 3º tapers. I scanned the appropriate page.


Of course I have a (3S) while you need a 3S.

How original do you want to keep this bike? I have a lot of used cranks and I'm just across the river from you.

Back in the day, a few people experimented with machining the races off of spindles and cups to accept cartridge bearings. It might be easier to machine down the spindle than the cups. So making new cups from 7075 aluminum would be an interesting project. I can show you some commercially made versions.

If you do remake the spindle from scratch, which would be easier with cartridge bearings - I just checked a drawer full of spindles and they had all been turned with a 2º conical taper before the 2º flats were done.

BTW I'm the last source on the planet for cotter presses, and send them all over the world. If you want to make your own, I can give you some tips.

Give me a call some time, sounds like we may have some common interests. My newest road bike is a 1986 Jack Taylor.

Mark Stonich; BikeSmith Design & Fabrication http://bikesmithdesign.com
5349 Elliot Ave S. Minneapolis, MN 55417 USA
Ph. (612) 710-9593 mark@bikesmithdesign.com
https://www.flickr.com/photos/bikesmith/ (Mostly Wildlife)
 

RCWorks

5 Star Possum Chef
Active Member
#17
I'd consider grinding a sealed unit to fit... I am somewhat of a brute on a bike needing replacement of 2 cassettes and 2 sets of chainrings and 4 chains per year. I have only had cause to replace unsealed spindles... I had to replace the 105 with a Ultegra and then a Dura-Ace before the shop said they gave up and put in a Phil Wood BB which has not failed, nor has my American Classic BB. The shell of the Bianchi with the 105 group was prepped with the right tool to cut the seat and align the bracket on the stationary side...

I have had a few mishaps on Raleigh frame bottom bracket shells(the frame part), including having the threads separate from the housing. I love the way their production bikes ride and the local shop warranted the frame 2 times before I gave up and sold it.

By the way, Phil Wood made sealed units in the 70's. I had one, but sold the bike... Look on eBay...

This is 6 months old and the cogs are steel. See the cogs marked with yellow arrows for deforming... While the gear trains fail those sealed Bottom Brackets just keep going. I clean and oil weekly.
 

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Mark Stonich

H-M Supporter - Premium Content
H-M Supporter-Premium
#18
I had to replace the 105 with a Ultegra and then a Dura-Ace before the shop said they gave up and put in a Phil Wood BB which has not failed, nor has my American Classic BB. The shell of the Bianchi with the 105 group was prepped with the right tool to cut the seat and align the bracket on the stationary side...

By the way, Phil Wood made sealed units in the 70's. I had one, but sold the bike... Look on eBay...
My wife is still using a late '70s Phil Wood BB and I just recenty retired one of that same vintage. Phil hubs and BBs are still at the top of the food chain. Although SKF BBs are held in similar high regard.

Last week we laid to rest a local cycling ledgend, "Blind Al" Fryck, the "Stoker From Hell". With him on the back all you had to do was steer and hope the brakes worked. After the service we gathered to tell stories about adventures, and mis-adventures we'd had with him on the back of our tandems. Back in '78 he put a 15 deg twist in the Phil BB on the back of my Paramount tandem. I assume there was a heat treat issue, but with Al anything was possible.
 

RCWorks

5 Star Possum Chef
Active Member
#19
I miss the old crew from Long Beach California, I figure many of them are "cruising clouds" these days. They took me in at 14, by 17 I was training with Ralph Therrio. The guy that turned me on to racing took me to my first club died in 1994, he was like a brother to me.

Before leaving California I used to repeat a memorial twin century the club had in honor of a member that died in the saddle. The most memorable of those runs was right after high school, I had graduated but was taking a guy one class down for his first try at 200 miles and we were unsupported. The AYH in Hemet is no longer in operation as was the restaurant we ate at on the overnight. He walks funny just thinking about it.

I did that twin century many times when I needed to clear my head. The course was life threatening back in the day... It was desolate desert roads, no cell phones, no water... It was all you and what you brought with you... It was a ride that demanded your attention... Today it's no longer the place for a warrior to prove his mettle, it's been civilized by the encroachment of people and homes and everything that goes with it.

My favorite bit of that ride... Wish it was still close enough to go.
 

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th62

Active User
Active Member
#20
They would be darn hard to machine. You could anneal them, machine them, and then re-temper them but the effort would not be worth it.
That's my opinion though. It IS possible.
Mark S.
There is a firm in England that sells bottom bracket parts in all sizes. I looked them up a while ago when I was building recumbent bikes/trikes. Casn't remember the name but if you try different wordings when googling you should find them.
 

jorglueke

Iron
Registered Member
#21
70mm shells were quite common on Raleighs and other brands owned by Raleigh. 70mm shells were usually 26tpi instead of the usual 24tpi. What bike and crank do you have? I'm into vintage steel bikes, and my entire business is based on cranks. Yet I'd never heard of a 3º taper. But checking my 1980 edition of Sutherlands, I see that some Asian spindles were made for 70mm shells and with 3º tapers. I scanned the appropriate page.
Hi Mark, this is a Sekine. 1974 SHS, made and assembled in Canada using Japanese parts. The crank is a SR, an early alloy with two rings.

How original do you want to keep this bike? I have a lot of used cranks and I'm just across the river from you.
I'd like to build this up almost both ways. What does it feel like with the original components, and what does it feel like with a new BB, crank. That said, since the original pieces are hard to find I'm not adverse to trying a 68mm English threaded sealed cartridge. One can always keep an eye out for another frame. I'm glad to see you make the cotter presses, I think I will buy one of yours. While machining is an interest as an add on to working on the older bikes right now time is a factor with the kids not that old. Kind of the same with ancient coins, die cutting and metalurgy are interesting but...