Cartridge bottom bracket - shell doesn't need facing. Why not?

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mikeymo
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Joined: 27 Sep 2016, 6:23pm

Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby mikeymo » 12 Jun 2018, 5:16pm

I'm planning the build up on this frame that I've bought:

https://www.biketart.com/bikes-c1/frames-c33/ridgeback-panorama-deluxe-frameset-p12171/s39221?utm_source=google&utm_medium=cpc&utm_term=ridgeback-panorama-deluxe-frameset-50-cm-2016-colour-burnt-orange-si-colour-burnt-orange-size-50cm-rba7650&utm_campaign=product%2Blisting%2Bads&gclid=EAIaIQobChMIt5G7gsLO2wIVCFXTCh22Pw0jEAQYASABEgI0UvD_BwE

Advice here is that if I'm fitting a cartridge style BB, which is what I'm planning, it doesn't matter about facing the BB shell.

Why not? That's a genuine question. As far as I can tell, external bearing BBs tighten against the shell, so the shell ends need to be square and flat, yes?

Do the cartridge ones not tighten against the ends of the shell? Looking at pictures, there seem to be lips on the screw cups, but do those not actually mate hard with the end of the shell?

P.S. some people have referred to 'square taper cartridge style BBs' implying that's the only sort of cartridge BB. But there are octalink etc. cartridge style BBs too aren't there?

mercalia
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Location: london South

Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby mercalia » 12 Jun 2018, 5:31pm

that seems cheap for a 853 frameset? £380? The fork also has holes cut thru thefork for front low riders, rather than eyelets that can break off. Seems to be a bargain. Facing? maybe becuase external BB come in 2 parts so they have to be square to one another? Facing also includes cleaning out the threads? On a normal square taper only one side actually bears any weight, the chainset side - the other side is often just a plastic space filler, that the left side rests on & is not a super tight fit over the shell? So the bearing are perfectly aligned to one another what ever. I assume other cartridge BB the same?
Last edited by mercalia on 12 Jun 2018, 5:51pm, edited 1 time in total.

goatwarden
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Location: Bristol

Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby goatwarden » 12 Jun 2018, 5:50pm

The reason for bottom bracket facing with external bearing BBs is that the two bearings are seperate pieces, each screwing into one side of the shell. Thus facing is essential to ensure that both bearings are pulled up to parallel faces and so the shaft should pass through parallel and aligned bores.
A cartridge BB is a single entity including the bearings for both sides so it doesn't really matter, from the perspective of bearing longevity, whether it is fitted square into the shell or not (although if it is seriously skewd you may notice on the pedal motion and it may be a problem.)

mikeymo
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Joined: 27 Sep 2016, 6:23pm

Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby mikeymo » 12 Jun 2018, 6:04pm

mercalia wrote:that seems cheap for a 853 frameset? £380? The fork also has holes cut thru thefork for front low riders, rather than eyelets that can break off. Seems to be a bargain. Facing? maybe becuase external BB come in 2 parts so they have to be square to one another? Facing also includes cleaning out the threads? On a normal square taper only one side actually bears any weight, the chainset side - the other side is often just a plastic space filler, that the left side rests on & is not a super tight fit over the shell? So the bearing are perfectly aligned to one another what ever. I assume other cartridge BB the same?


Yes, I thought it was cheap. Though it was a bit of an impulse buy. The general opinion is that on touring bikes it might not matter that much. The And worth pointing out that the main triangle is 853, but the seat and chain stays are 525 and the fork 520. The current Panorama Deluxe is 725 throughout I think. I wish mine had lugs for a third bottle cage, but they've put the runners for the brake cable on the lower surface of the DT, so presumably that's why they couldn't.

iandriver
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Location: Cambridge.

Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby iandriver » 12 Jun 2018, 9:02pm

I suspect it's cheap because it's such a small size and they can't shift it. It's common for 853 frames to be main tubes only, the rear triangle other grades. It has a reputation for being stiff also, but with sensible sized tyres will no doubt be fine. Love my 853 frame.
Supporter of the A10 corridor cycling campaign serving Royston to Cambridge http://a10corridorcycle.com. Never knew gardening secateurs were an essential part of the on bike tool kit until I took up campaigning.....

mercalia
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Location: london South

Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby mercalia » 12 Jun 2018, 9:19pm

iandriver wrote:I suspect it's cheap because it's such a small size and they can't shift it. It's common for 853 frames to be main tubes only, the rear triangle other grades. It has a reputation for being stiff also, but with sensible sized tyres will no doubt be fine. Love my 853 frame.


same with my Dawes 1-Down. The main tubes are 631. The forks cro-mo dont know what the rear triangle is. 54 cm max is a bit small. Mine is 57cm

mikeymo
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Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby mikeymo » 12 Jun 2018, 11:06pm

Interesting that you both think 54 cm is small. Not saying you're wrong, but I'd be interested to know if you've tried any of Ridgeback's touring bikes.

My other bike is a Ridgeback World Journey, which is their Alfine 8 tourer. I've got it in 56cm. The first thing I did was put a shorter stem on. My more experienced biking chum said that was the first thing that struck him, how long the stem was. Many people find Ridgeback tourers a bit 'long' and replace the stem, even including Tim and Laura Moss (who Ridgeback use in their own advertising material!):

https://tomsbiketrip.com/ridgeback-panorama-review/

Even with a shorter stem on I find my 56cm Ridgeback tourer a bit long. So on the basis that the geometry will be roughly similar I went for the 54cm, bearing in mind that you can make a slightly too small frame bigger, but not the opposite. With my World Journey I've spent a bit of time trying to make it smaller - shorter stem, saddle as far forward as possible etc.

I hope this isn't going to prove me wrong. I'm 5' 10" and my inseam is 32" (if I've measured correctly). I know that puts me in the 56 cm range, but I think it's a bit big. We'll see.

I've held this frame up against my 56 cm World Journey, and to be honest there's little difference. The actual top tube (not 'effective') seems to be about 5mm shorter on this. But the seat tube lengths are as per size. Of course the worry now is that the head tube will be too short, but as I've got an uncut steerer (at the moment), at least I can use a few spacers.

mikeymo
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Joined: 27 Sep 2016, 6:23pm

Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby mikeymo » 12 Jun 2018, 11:16pm

On the subject of 'cheapness', what the chap at Biketart said was that Ridgeback just messed up and made way too many of these frames. I think there's a lot of them hanging around.

It looks to me as though this happened:

1. Ridgeback made a (relatively) hi-spec disc brake tourer, 853, 10 speed Tiagra etc. Using this frame, but in green, they sold if for MRP of £1700.

2. Not many people bought it, because at that price, and for the target audience, there was a lot of price resistance and too many people who wanted to change things. This groupset, those ratios, these calipers etc. etc.

3. But Ridgeback still thought there was a market for disc tourers in expensive steel, so they sold the frames. They might have already made them and just sprayed them a different colour. So they tried to sell the frames for £750. Bob Jackson near me sells touring frames for about £650 in 631. And you can get disc fittings and forks for a bit more. Plus you can personalise it a bit. So nobody really bought Ridgeback's frames.

I think that's how they've got to this point.

As a matter of fact I might not keep it. I've been careful to make sure it's still returnable, and it's becoming clear how much it's going to cost me to build it. Come the autumn sales it's perfectly possible that the current Panorama, selling for £1350, will be at the same price as this might well end up costing me.

peetee
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Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby peetee » 13 Jun 2018, 12:31am

Am I alone in thinking that frames made with quality tubing such as 853 (and from some lesser tubing, for that matter) should have the bottom bracket and headset surfaces faced before they get anywhere near a customer?
Current status report:
Latter side of fifty and feeling less than nifty.
Too many bikes on pegs and too few miles in the legs.

mikeymo
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Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby mikeymo » 13 Jun 2018, 12:34am

peetee wrote:Am I alone in thinking that frames made with quality tubing such as 853 (and from some lesser tubing, for that matter) should have the bottom bracket and headset surfaces faced before they get anywhere near a customer?


As I said, I think they might be on this. At least the head tube. I've actually emailed Ridgeback asking them, but they've not got back to me.

yostumpy
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Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby yostumpy » 13 Jun 2018, 8:09am

I have "Olive", the green one, picked it up for £999 at Swinnertons, xmas 2015, complete. I swapped the hollowtech chainset for a campag set that I had with BB, no issues for 18 months ( 10,000 km?) . Now just swapped again for Stronglight Impact triple and shimano square taper hobby, again no issues. The stem I also changed. It came with a 120mm and bars with short ramps, so I put nitto noodles on( which have looong ramps, and a 100mm zero rise stem. It is a good price for the frame, and unless you go silly, could be built up reasonably cheaply. I still have the 10 speed brifters( virtually unused) wheels, 120 stem, bars, seatpost, if you are interested, but I suspect you'll want new.

Brucey
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Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby Brucey » 13 Jun 2018, 9:04am

re BB facing; it matters less if you plan to use a ST cartridge BB but that is not to say that it doesn't matter at all.

If you plan to use a HT-II BB, you can measure the BB shell length at various points using set of vernier calipers; if the length is uniform the BB shell is probably OK. You can measure the length of the assy with the cups installed too; again if the length is uniform the BB shell is probably good enough.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

iandriver
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Location: Cambridge.

Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby iandriver » 13 Jun 2018, 3:35pm

mikeymo wrote:Interesting that you both think 54 cm is small. Not saying you're wrong, but I'd be interested to know if you've tried any of Ridgeback's touring bikes.

The link above shows a 50cm frame, that is what I was thinking of.
Supporter of the A10 corridor cycling campaign serving Royston to Cambridge http://a10corridorcycle.com. Never knew gardening secateurs were an essential part of the on bike tool kit until I took up campaigning.....

mikeymo
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Joined: 27 Sep 2016, 6:23pm

Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby mikeymo » 13 Jun 2018, 4:09pm

iandriver wrote:
mikeymo wrote:Interesting that you both think 54 cm is small. Not saying you're wrong, but I'd be interested to know if you've tried any of Ridgeback's touring bikes.

The link above shows a 50cm frame, that is what I was thinking of.


Ah, right, apologies. I think it's a drop down list thingy. Mine's a 54cm.

mikeymo
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Joined: 27 Sep 2016, 6:23pm

Re: Cartridge bottom bracket - shell doesn't need facing. Why not?

Postby mikeymo » 13 Jun 2018, 4:11pm

Brucey wrote:re BB facing; it matters less if you plan to use a ST cartridge BB but that is not to say that it doesn't matter at all.

If you plan to use a HT-II BB, you can measure the BB shell length at various points using set of vernier calipers; if the length is uniform the BB shell is probably OK. You can measure the length of the assy with the cups installed too; again if the length is uniform the BB shell is probably good enough.

cheers


Just done that, with a vernier, but one without the fancy shmancy digital read-out. Still, as far as I can tell, it's pretty much smack on 68mm all round. Tiny variations really depending on how hard I pushed the caliper jaws against the paint.