musicsucks

my crankset and bb finally came in the mail today which made me very excited. I rode over the the bike co-op and tried to install it and doesn't fit- too small. The (very nice) guy at the co-op told me that i should support my lbs. I guess he's right.

anyways
The new bb i got was an (octalink) 68x109. It seems like my only other option is a 70x109- (italian threading) Will this solve my problem? Is there anything else it could be? The old bottom bracket was a older (circa 1987) shimano 600- it says 36x24t on the side and the bike is an older (again '87ish) marinoni. I assumed since they are a Canadian company that they would just use the english 68, but i have heard from people that they at some point used Italian. Is there some way that i can measure before i drop more money on a new bb that may or may not fit?

vpiuva

36x24t is Italian thread. Your English one just dropped right in that ol' hole, didn't it?

musicsucks

yeeep.
I did a pretty piss-poor job of putting the old one back in too... it feels pretty crappy right now and i think i might just have to live with it until i can get an Italian bb.

JunkYardBike

I may be wrong, but it seems whenever I'm searching for a cartridge style BB, the Italian thread 70 and 73 mm jobs are always the bargain basement deals.

musicsucks

allright, hold the phone.
73mm?

If it's just 68 and 70, we're cool- i'm halfway there already. Is 73 a possibility? Should i measure? and what do i measure?

vpiuva

No, yours is definitely not a 73mm

JanMM

Ideally, you measure before you order the BB.

musicsucks

i realize that i'm showing my true newbie/hipster colors, but i don't even know what to measure. It seems like the 68/70 should refer to diameter- but near as i can tell the diameter is 40mm.
maybe circumference? that doesn't really work out either.

JunkYardBike

It's the width of the shell, parallel to the spindle (i.e. from driveside to non-drive side).

I've only ever dealt with 68mm shells, so I can't be certain, but it seems 70mm shells may also have a wider circumference, hence the fit issue. Maybe a built in warning system that you have the wrong width BB?

well biked

The measurement refers to the bottom bracket shell width on the frame. Actually, there's often some slight variation, particularly on older frames (they used cup and cone bottom brackets), but since you've found the markings "36 x 24" on the old bottom bracket, there's no question it's Italian threaded so you should have a 70mm bottom bracket shell on your frame, or something very close to that. So your 68 x 109 bottom bracket is an English threaded bottom bracket intended for a frame with a 68mm bottom bracket shell, and the spindle is 109mm long. The most common, by far, for road bikes is 68mm English thread. English thread is left hand threaded on the drive side, and right hand thread on the non-drive side. This prevents the bottom bracket from unscrewing from pedaling forces. The main problem with Italian threaded bottom brackets is that they use right hand thread on both sides, and the drive side will have a tendency to loosen over time from pedaling forces. 73mm is almost always a mountain bike size-

DMF 

Is the 109 length appropriate? How many gears up front?


== oxymoron

vpiuva

I forgot to ask are you replacing the crank.(I assume you're using a double) Because if you're not replacing it, the Octalink style BB will not fit your 1987 tri-color 600 crank. That one needs a square taper. I think my identical Italian 600 job used a 116mm loose ball BB. You should still be able to find square taper Shimano BBs, but sealed, in the 115mm length

HillRider

+1. If you bought an English threaded bottom bracket you got the wrong one. Yours is certainly Italian.

tellyho

You need to do some research. A lot, it sounds like. The world of bb sizing and crank compatibility is a complex one. Check Sheldon's site and read up.

musicsucks

The funny thing is that i spent a lot of time doing research.
I got a ultegra road double (splined), which is going to become a fixed single. I spent so much time freaking about about keeping my straight, 45mm chainline (i think i did pretty good not to just go for the triple that gives technically a 45mm chainline but figuring out that the 43.5mm chainline of the double means that the big ring is at 45) that i didn't even really think about my frame being Italian. Marinoni is a canadian company forchristsakes.

also: i thought newbie/hipster was redundant?

operator

I think you meant synonyms.

vpiuva

What type of rear hub? Most track & flip/flops are made for a 42mm chainline.

DMF 

No. A hipster is someone who is hip, who knows what's going on. A newbie doesn't.

wtex

I think this guy would go with synonymous:

https://bikesnobnyc.blogspot.com/

musician

Marinoni -- sounds Italian to me.



just joking, i know that probably wasn't helpful. hope it works out.

HillRider

I assume a Canadian distributor imported bikes, or at least frames, from Italy and in the late '80's a number of Italian frame makers still used (doh!) Italian threading. By now most have converted to English threading but there are still a few hold-outs.

BTW, Italian threading is an inherently poorer design as the non-drive side cup tends to unthread itself unless installed VERY tight and/or with Loctite.

musicsucks

Sorry for bumping an allready silly thread.

So; i went looking at all the bike stores in town figuring that if i've learned anything from this buy-wrong-stuff fiasco is that i should support my lbs. The only 70x109 bb i could find was an old Dura-Ace, so i got a deal on it since it was old and looked like it had been a little used (still way more than i wanted to spend) and this guy at the shop put it back together (said that someone had just taken it apart- he was super friendly and gave me lots of advice on installing it and sounded like he genuinely cared).

Anyways- I found my way to my local bike co-op since i don't own bb tools and i tried to get it in- and while it is much closer than the old one; the threads still wont take. Since i got a lecture from the guy who sold it to me, i didn't try to force it (seems like a good idea right?) but i can't figure out why it doesn't work. It is deffinatly marked the same as the one i pulled out- the only difference being that it's a cartridge style and splined- oh and won't install.

Anyways- i'm pretty much just going to give up and get LBS to install the bb. this sucks. the only reason i got a new BB was because i thought i should learn how to install it and now my old bb feels like balls and i can't use my new cranks.

HillRider

Cartridge bottom brackets often come with teflon tape or a sealent factory applied to the threads so they will take a bit of effort to screw in. You have to be able to tell the difference between the feel of cross-threading and just a snug but proper fit.

You do know that Italian bottom brackets are right-hand (conventional) threaded on both sides?

vpiuva

I've had interference issues installing a cartridge BB in a shell that once had a loose bearing one. Look and feel inside the shell - the screw that holds the BB cable guide may be too long, or the tubing may extend just a little too far into the shell. The first is any easy fix, the second (like mine) required a little grinding. Or it could just be that your threads need chasing.

DMF 

+1

Or cleaning. Some grit in the threads will stop your fingers dead.