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Thanks Shimano for the useless diagram, it's guaranteed to make my brain hurt every time I come to fit a new bottom bracket and realize I haven't noted which side the spacer goes.
If you can tell me which side it goes, that'd be great, or maybe supply some other examples of completely useless diagrams that cause brain ache?
Insert Tab A in to Slot B.
Isn't it obvious?
I can't say I'm currently orbiting it.
Drive side
Drive side is on the right I guess. It's obvious, but the diagram shows the frame from beneath where the drive side would be on the left?
That must be one of the most simple diagrams ever.
68 & 83mm, 1 spacer NDS, 2 spacers DS
73mm 1 spacer DS
Lemmings
But from what projection are we looking?
I'd say the diagrams are looking down on the bottom bracket so are correctly "handed".
I just put the BB in and move things around if the chainline isn't right.
Also head scratching is shimanos diagram/explanation as to which direction to join a chain.
The spacer takes the place of an E-type mech. If you're not using one then it's one spacer on the drive side. If 3 are required then it's two on the drive side, one non-drive side.
I've put it drive side now 😁
So, same amount of the same spacers for 68mm and 83mm?
As far as diagrams go, that's a pretty simple and straightforward one.
I'd suggest it was someonething else that was useless.
Sorry diagram is so obvious. User error 😋.
Why is that not a view of the BB she’ll from below? There is no seat tube indicated. The tube inside can be mounted to either side before insertion, only the cups are threaded for handedness orientation.
And if that alien offers to shake your left hand?
The universe is handed. Who knew?
As far as diagrams go, that’s a pretty simple and straightforward one.
I’d suggest it was someonething else that was useless.
Just wait for the "my chain is too slack" post because its got 4 extra links in not 2...
For my Deore BB-M52 the cup with the sleeve is drive side which makes it fairly clear (I assume that this is standard for Shimano bottom brackets).
The sleeve is not permanently attached to either cup so that's not a good guide.
My favourite is the diagram from the assembly instructions for those ubiquituous cheap square IKEA side tables. The last step illustrates the table being turned the right way up... as if you might have fully assembled it and then been confused as to why it wasn't functioning as desired because the legs are pointing upwards.
PJay
Member
For my Deore BB-M52 the cup with the sleeve is drive side which makes it fairly clear (I assume that this is standard for Shimano bottom brackets).
this
out of the same box those instructions come in a Shimano bottom-bracket always has the sleeve attacked to the driveside cup, it's not hard
So you're fine so long as you only ever install BBs directly from the box?
That diagram is not good. When I look at the picture my brain tells me I'm looking at the bike from below. However, since I know the spacer goes on the drive side I know it must be from the top.
A diagram that requires you to already know what the diagram is supposed to be telling you is not a lot of use.
BruceWee
Member
So you’re fine so long as you only ever install BBs directly from the box?
this is going to be the case in the vast majority of cases though isn't it?
unless you're like the OP and come to fit a new bottom bracket and not noted which side the spacer goes on the old one, which is a lack of very basic mechanicing skills
Agreed, diagram like that should always note the view direction or inc L and R
Seems straight forward to me unless you fit parts to your bike with it upside down.
Why is that not a view of the BB she’ll from below?
Should always be from above, unless indicated.
Very simple diagram.
For the sake of adding L and R they’ve got a diagram which relies on you either having a box-fresh BB (or one which by pure luck has the tube attached to the drive side cup) or being able to figure it out (in which case you probably didn’t need the diagram anyway). Two letters and the diagram works for everyone in every situation. It’s great if it seems obvious to you, but (quite clearly) it doesn’t to everyone.
Why is that not a view of the BB she’ll from below?
Because the instructions assume it's being built by a mechanic in a workstand, not bodged upside down on the floor.
Same reason the headset instructions probably don't show it being tapped in with a hammer and torques are given in numerical values not "finger tight with a small hex key".
Because the instructions assume it’s being built by a mechanic in a workstand, not bodged upside down on the floor.
Where's the seat tube? Assumption is the mother of all cock-ups - well home maintenance ones. An L/R or just a circle indicated in the presence of a tube would help. New bare frame, used BB bought online from here with two cups and separate tube, no reference point...
It's not an assumption, the drawing is an elevation, ie from above. Have you ever seen house plans, or any other plans for that matter from below? no, thought not.
Even if it is obvious that the diagram is being viewed from the top because it's in a workstand (I'm not 100% convinced by that logic but for the sake of argument let's say it is) that still leaves the problem that the diagram looks like it is from the bottom given the fact there is no sign of the seat tube.
It's confusing. If you already know which side the spacers go on then of course it's obvious but making a diagram that requires you to know what it is supposed to be telling you is pretty useless.
And as for the 'you'll always be fitting them fresh from the box' argument, relying on undisturbed perfect packaging is not a substitute for putting the words 'Drive side' on the diagram. It shouldn't increase ink costs significantly.
It’s not an assumption, the drawing is an elevation, ie from above.
But you're apparently well-versed in the conventions of house plans etc.
These instructions don't just need to work for someone who's familiar with planning applications, they need to work for any old sod in a shed who's looking at a bicycle frame with a bottom bracket in their hand.
That bicycle might be in a workstand, or it might be parked upside down on the floor. That person might be an experienced cycle mechanic, or a mechanically disinclined dad who can't afford bike shop labour costs trying to fix his kid's bike.
The confused dad isn't helped by someone on the internet saying it's obvious to him. He's helped by adding two letters to the diagram.
In other words, you are making an assumption: you're assuming that whoever is reading the instructions is as familiar with diagrams and/or bottom brackets as you are.
It’s not an assumption, the drawing is an elevation, ie from above. Have you ever seen house plans, or any other plans for that matter from below? no, thought not.
Have you ever seen a bike viewed from above where you couldn't see the seat tube? No, thought not.
I had the wordy version of that on my old photobucket page because it was really useful!
cos it has the front mech mount in one of the pics, makes it obv which is driveside.
Here 🙂
Have you ever seen a bike viewed from above where you couldn’t see the seat tube?
Yep. Most of the time the saddle obscures it.
hang on.
All these diagrams seem to show a cross section of the frame (hence no seat tube being included, threads being visible etc) but not of the actual BB.
that's just wrong
Heaven help them when they're changing pedals then!.
Perhaps you want a saddle and dropper in that elevation as well then Brucie?. 🙂
Actually, I'd settle for the words 'Drive side'. That would be simpler, wouldn't you say?
By the way, the diagram is not a 'plan'. No one is going to be using it to machine parts. It's an assembly aid so the view can be whatever makes the instructions clearest. Haynes manuals don't restrict themselves to taking pictures from directly above.
Fair enough, aye DS would be easier, but it's really no hard to work out. You would think... 🙂
wtf buys 2nd hand BB's btw!
Enlightening how many people think things are obvious to everyone because it happens to be obvious to them. Male brain?....
Heaven help them when they’re changing pedals then!
No, better diagrams help them 🙂
Seriously, I see this all the time*, this is my job. People make stuff which users don't fully understand, and one of the main causes of the problem is the Curse of Knowledge: when the people making the stuff think something is obvious, but the users don't.
It's one of the reasons why user research is central to good design: you get to find out that the things everyone thought were obvious aren't. You also try to understand why that is, then you design a way to fix it, then you test it again—you don't just go "well if they can't cope with task X, then they're screwed for task Y" and walk away. (Try testing the above diagram by giving half a dozen randomly chosen bicycle owners a fully dismantled bottom bracket and a bike upended on its saddle and handlebars: if not one of them struggles I'll eat my pedal spanner.)
* not least whenever I try to use this website 😀
wtf buys 2nd hand BB’s btw!
I've quite often transferred BBs between frames, and I've quite often stored BBs in a box for a a long while before needing to fit them again. I suspect in the past I've bought secondhand chainsets with BBs included, too.
If you buy a NOS/OEM/unboxed one from eBay or wherever then it might turn up in a slightly different arrangement to a box-fresh retail one, too, I guess.
You have to remember that many bike shops have component fetishist gremlins lurking. When I worked in the shop it seemed like every part had been taken out its box, removed from it's plastic bag, fondled, and then put back into it's box with the plastic stuffed in afterwards.
I agree that putting L-R or Drive Side on the diagram would make sense.
If I recall correctly, the only instructions that came with my BB directed me to the Shimano website for installation instructions, which I found in the form of a number of Dealers' Manuals.
The diagram I found was:
[img] 
?psid=1[/img]
The text to the right does make it possible to work out the left & right sides, but again simply orientating the diagram would be the simplest option:
"If using three 2.5mm spacers with a
band type and a bottom bracket shell
having a width of 68mm, install the
three spacers so that there are two on
the right and one on the left.
Does it not say on the instructions "should be installed by a competent mechanic"? If not, maybe it should.