MarkN

I have, right now in my hands, a bottom bracket. I would like to install it. So far so good in every respect but one; the bottom bracket is just sitting there in one piece making me feel extremely stupid right about now. It is one of these;

https://www.highonbikes.com/tifosi-ca...m-bracket.html

A Tifosi campag fit square taper (ISO) English threaded 102mm long common or garden bottom bracket.

I cannot for the life of me see how to get the left cup off the spindle. It spins freely and shows no inclination to come off no matter how I try to coax it off.

Please. What am I missing here?

[edit] The left cup is supposed to come off, isn't it? So confused.

bikeman715

yes the left side cup should come off .

ultraman6970

It should come off,,, try with some wd40 and pry it with a screw driver little by little.

MarkN

And when we say it should come off, we mean the thing should just come off right? I mean, I've had ones before where this is what happens. But, pull as I might, this one just spins and does not budge up at all.

It feels like some kind of practical joke. Some kind of christmas cracker bottom bracket. Either that or it's so super clever and high tech that I couldn't possibly summon the synergistic dynamics required to install it. I'd have thought that kind of tech would cost extra.

oldbobcat

Might be time to swallow pride and call the people who sold the thing to you. But before you do, try this. I have a hunch the red ring to the inside of the lock ring spins, and there's some sort of interlock between this ring and the lock ring. Try rotating them in opposite directions and seeing if that doesn't free it. Just a hunch. I've never seen one of these bottom brackets before.

ultraman6970

This is what you can do, use the lock ring from an old style BB cup... put that thing in the 1st few threads and tap it with a hammer, work around untill you get it off.

Second way to fix the problem, if you have an old frame moving around or even the frame you want to stall the thing to... thread the 1st few mms of the cup into the BB shell and pull... personally I would use an old frame.

onespeedbiker

I've seen BB like this before and because the BB housing is carbon there are red lockrings on both sides and the bearings are pressed into the red lockrings. You'll see a small gap between the cup and red lock ring; the red ring is tapered so the farther the cup is pushed on the harder it is to separate. I would not use a screw driver as both red lockring and cup are aluminum and are quite thin (the lip of the red ring and last 3-4mm of the cup that has been thinned out) and there is a good chance you will gauge or crack something.The easiest way to separate the left cup is to take an old lockring from a loose ball BB and screw in on the end of the left cup (as ultraman6960 advised, but instead you are going the tap the left end of the spindle). Then either wrap a rag around the cup or open the jaws of a vise big enough for the BB to fit through but not the lockring and just pound on the end of the spindle until the cup comes loose. You might want to wrap the cup threads with duct tape to protect then from the vice and either use a wood hammer or place a piece of wood or aluminum over the end of the spindle so you don't do any damage (realistically I doubt it would take that much effort, but it pays to be take precautions just in case).

MarkN

Thank you thank you guys, brilliant. Didn't have the described old lockring to hand, but wrapped rag round the threads on the left cup and gripped it in a wrench. Braced the wrench against a table and nocked on the left spindle with a wooden thing until it slid through the cup. No damage done. BB ready to isntall. Cheers!

MarkN

Argh, mayday mayday. Have encountered a problem installing it.

The left cup spins into the shell perfectly happily. The right side, however, grips after a few turns and starts stripping threads if pushed.

The old bottom bracket was a Miche Primato Track bottom bracket https://www.parker-international.co.u...m-Bracket.html 107mm long English threading... new 4 months ago. Shell threads chased and cleaned at the time.

Umm... have I phooked up here? Was sure the new one would be compatible

(edit - for reference, the reason for the change is a chainline issue although, as it happens, the Miche Primato BB is starting to feel a little crunchy anyway).

anixi

Mayday? More like Mayhem! Take the frame to the LBS and have them chase the threads before you really muck it up. The LBS may just have a replacement cup for you to cobble it all back together. Sounds like a bloody mess...

MarkN

After a lot of testing and measuring and head scratching, I may have discovered the source of the problem. I checked the threads on the old and new bottom brackets; they're fine (the stripping I previously observed was superficial). I checked that the old bottom bracket still goes into the shell; it does. So why does the new one get stuck and grind?

The only difference is that the new one has a higher flange behind where the left cup sits. After an attempt to insert the spindle, I observed some scraping on that flange. A look inside the bottom bracket shell reveals that the down tube protrudes a short way inside the shell, enough the scrape the flange on it's way through. So, if i file that down a bit it should be good to go, right?

I'll report back...

MarkN

Ok, that worked. BB installed. But wow, that was harder than expected. Now for the cranks... at this rate they'll have turned into leeks since I last looked, or something. The plan; Tifosi 102mm BB + Miche Primato Advanced cranks VS Dia Compe Gran Compe hub + EIA cog = perfect 41.5mm chainline. Here's hoping...

ultraman6970

Good description mark, thats exactly how it works, it is designed to tight really good as deeper it gets, by the way, did you put grease in the threads of the BB shell right? U really dont want that to freeze in there. I have a token of those BBs and are really non troublesome but you really have to do as with any BB cup, grease and teflon tape just in case. Probably you wont take it out ever but you never know.

For the record, the cranks might turn harder. Those things have seals in the cups. Not that will take like 90% of all the power you put to it but in case you wonder it will be like that for a few months until the seals worn out and the bearings get more miles.

onespeedbiker

I like to think the seals wear in, but you could be right..

MarkN

Cheers Ultraman6970 - yeah, I greased that sucka up good n' propa. Thanks for the hint on the seals