SHARTQ'S


#1

I’ll start with a good one!

Bottom brackets come in different sizes … right? How do I know what bottom bracket will fit my bike and what brand I should get? I want something cheap and low-end because it’s going on a pos grocery bike.


#2

I know I encouraged you to start this thread, but I now realize that it’ll probably consist mainly of links to Sheldon Brown. Here’s one: http://www.sheldonbrown.com/bbsize.html


#3

:facepalm:

Wait, wait, no. Trying to read that page is like trying to read French - I see words that are familiar to me but I do not have to background (crankset) to understand the context.

Oh, double wait. BB size is dependent only on crankset? I could just shove any old thing in there and then try to find the appropriate cranket? Wh-what.


#4
www.sheldonbrown.com

/thread


#5

Sheldon does not always answer things in ways I understand! Grr.


#6

Scroll down towards the bottom of the link I posted. Your choices are English, Italian, French and Swiss. If it’s for that khs you posted, you’re gonna need an English bb. All you need to figure out is the right spindle length for the cranks you’re gonna use.


#7

I know you don’t really want another website, but www.parktool.com/repair has everything too. It’s good sometimes for another perspective.


#8

Just get a book

http://www.amazon.com/Bicycling-Complet ... pd_sim_b_1

This one explains everything pretty layman.


#9

Okay those are all good suggestions. Sometimes a girl just likes to interact with humans, even internet-humans.


#10

I haven’t look much at cranksets - I honestly don’t care what I use as long as I don’t die and it’s cheap. If anyone has a low end set of 170 or 165 hanging around … you know what to do.
The brand is KHS, model is Winner. Judging by this sticker set I’m going to guess it’s from the late 80’s. Serial number is 70463337. According to their serial number guide it was made in April of the 7th year of some recent decade. So. 1987?


#11

thanks for asking that because i was going to ask about that at some point. my bike is rapidly deteriorating and my birthday is coming up and i have a nishiki frame that i got for free, so i am probably going to use this thread to ask all the dumb purchase questions i have, of which there will be several because i don’t know what i’m doing at all.


#12

We will learn together.


#13

Easiest thing to do is to get the Sugino RD crankset and matching BB, or the IRO crankset and matching BB.

If you really want to save money, first get a JIS square taper road double or triple off Ebay. Shimano 105 or 600 would be best, but you can make a Sugino VP or Sakae work fine. Just make sure the drive side crank is not swaged (crimped permanently onto the large chainring). It should have 5 arms, 5 chainring bolts, and 2-3 chainrings. Make sure you get them all together because bolts and rings cost $$ new. You shouldn’t expect to pay more than $35 total for a 170mm set. 165mm sets go for much higher, even if they’re crap, because some people think they’ll die without them.

THEN once you have your crankset, go to your local bike co-op and explain you need a regular 24x1.37 bottom bracket (2 cups, 1/4" bearings, lockring, spindle). They should have a whole bunch of used ones. Also explain that you need to figure out which spindle will give you the right chainline with your cranks. For example, most Sakae cranks (chainring on inside) will give you a ~42mm chainline when matched with a 3NN spindle. You may have to try a few spindles before you find one that gives you the right chainline. You can also flip a spindle around since one side is usually longer than the other. You can put a spacer between the fixed cup and the BB shell. As long as you get the spacing with 2-3mm of 42mm you’ll be fine. This is assuming you’ll be using Formula or Joytech hubs (some other hubs have 45mm chainlines).

If you don’t have a local bike co-op, maybe an LBS that rebuilds old bikes can help you. Just don’t let them rip you off. Or other tarcksters might be able to help. I’ve got an extra set of cups, you can get the bearings at a hardware store, then it’s just lockring and a spindle.

But yeah, first get a crankset.


#14

Nashbar has a $30 crankset for hybrids and whatnot if you want new parts. You could probably find something at one of the various bike parts recycle places or a coop or something.


#15

frankstoneline suggested this

http://keirinculture.com/store//catalog ... cts_id=402

iros website says the bb has a 68mm shell


#16

This is exactly the kind of interaction and advice I was looking for - that makes a lot of sense, thank you! We do have a co-op, the Bike Kitchen. And I’m a member! How bout that.


#17

Don’t buy a BB 'til you know what cranks you’ll be using.


#18

If you use an older quality crank, I’ve had good luck with 110mm BB spindles. I switched between the crap that came stock on a fuji track to a Gipiemme to a Sugino Super Mighty. They were all converted road doubles and they all gave a chainline within a mm of perfect.

I wouldn’t go with a loose ball BB unless you have to. It is nice to learn how to overhaul them and stuff, but for day to day riding, having a reliable cartridge bearing BB is nice. The cheap shimano square taper BB is about $25 to $30.


#19

Yeah. Bottom brackets are pretty complicated; you have to consider shell diameter, threading, spindle type, and spindle length. The first two things basically determine whether or not the blasted thing will screw into your frame properly, while the third determines if the cranks will fit on the spindle and the last (on a singlespeed drivetrain) determines the chainline the cranks have.

The advice of “know what cranks you are using before selecting a BB” is perfect, as you have to make sure the thing will interface your frame and cranks properly as that is its function.

If you’re looking at an older JIS taper Shimano 105 or 600 crankset (like the one I recently bought hells yeah!) which is something I recommend you’ll get a pretty perfect chainline to a standard track hub with a 107mm BB spindle. They are on the internet, I actually just got a set of 4 shimano sealed bearing bottom brackets for like 20 bucks on eBay. It’s easy to find hella deals if you know what you’re looking for, so get cranks first.

Sorry if this post was too Bikeanese.


#20

[quote=“blackholelectron”]Yeah. Bottom brackets are pretty complicated; you have to consider shell diameter, threading, spindle type, and spindle length. The first two things basically determine whether or not the blasted thing will screw into your frame properly, while the third determines if the cranks will fit on the spindle and the last (on a singlespeed drivetrain) determines the chainline the cranks have.

The advice of “know what cranks you are using before selecting a BB” is perfect, as you have to make sure the thing will interface your frame and cranks properly as that is its function.

If you’re looking at an older JIS taper Shimano 105 or 600 crankset (like the one I recently bought hells yeah!) which is something I recommend you’ll get a pretty perfect chainline to a standard track hub with a 107mm BB spindle. They are on the internet, I actually just got a set of 4 shimano sealed bearing bottom brackets for like 20 bucks on eBay. It’s easy to find hella deals if you know what you’re looking for, so get cranks first.

Sorry if this post was too Bikeanese.[/quote]

To say bottom brackets are complicated is pretty silly. The first two bits of information should have been taken care of when you selected a frame (BB shell size and threads) and its really not worth it to dick with stuff that isnt standard if you are trying to find a BB for it. Spindle length is really the only concern, because presumably you are using it for square taper cranks, rather than splined stuff. So really, you just find the cranks you want, and then look up the manufacturer specs on them. If you are using a road double, you have some play, as you’ve got both chainring positions to use, so you can add a mm or 2 or subtract them and still have a setup that will offer you a proper line. As it’s a beater you really only need to get within 2 or 3 mm of the 42mm chainline, and even if it wasnt chainline isnt nearly as important as people make it out to be. Also, theres really no reason to not get the cheapest bb you can find, generally older loose ball shimano setups from a bike co-op.