YST - 7NL Cup & Cone style Bottom Bracket advice needed

[drexal77]

Hi guys,

Hope your all well. I started riding my 34 year old alpine stars Al-Mega XT (as its just been sitting there waiting to be restored for so long and so couldn't resist any longer. I noticed the crank has started to move around more and more on each ride and i've worked out its the spindle in the BB.

I bought a park tools HCW-4 BB wrench and managed to get the none drive side off buy turning anticlockwise it came off easy. But the drive side is stuck solid, i ended up snapping the pin off the new tool, so i left it soaking in WD40 then bought a park tools SPA-1. But still can't shift it.

So i just wanted to check with you that this isn't a left hand thread, research seems to say it is, but the park tools BB video says to remove this drive side pin style BB anticlockwise. I've tried turning both ways but no joy.

Is there any way i can check if its left or right thread?

I also don't really have a huge array of bike tools or a blow torch / heat gun. And my local bike ship is super expense and i would much rather not be beat by this and do it myself.

Heres some images of it.

Thanks to anyone that can help.

 

[bikeworkshop]

I'd grind flats on it (like the other side) and then bolt a tool on there for maximum grip.
The heat generated and the vibration also help break the bond.
You might mark the bb shell if you're not very careful, but it will be hidden by the new bb lockring.

Those pin spanners can't apply enough force to remove most steel cups in alloy frames if they haven't moved in a quarter century.

 

[drexal77]

Hi @bikeworkshop thanks so much for replying and offering advice. I would have never thought of that in a million years and if i can do a good enough job, i don't think anyone would be able to tell and i might be able to re-use this original BB if i can clean up the bearing enough etc. Just one other question, is there a way i can tell if the thread is left or right? So i 100% know which way to turn it.

 

[27motorhead]

LHS side cup (non) drive side will be a right hand thread. So undo anti-clockwise. If you removed the lockring from it, this will confirm this when you try to refit it. As it is exposed you can also view the start of the thread which will also indicate whether the thread on the cup is left or right handed.

The RHS cup is the trickier one as these can be either left hand thread (English) or right handed (Italian) and as you cannot see the thread at all due to the shoulder of the cup hiding the start of the thread.

There is another trick with using a stud & nuts that pinch against the cup and grip it and rotate the cup with them at force. This is normally done on the drive side cup if English threaded as this action removes it. You can still do this on the LHS cup, but you will tighten it, but if it moves one way, it should move back the otherway (but the nuts will undo) and you'll need your repaired pin spanner or grind flats on the exposed bit of the cup.

Good luck!!!

 

[27motorhead]

This thread regarding stud/nuts/sleeve...
https://www.retrobike.co.uk/threads/fixed-cup-removal-with-pics.456107/

 

[bikeworkshop]

Adjustable cup (the one with a lockring) is always a right hand thread, French, Italian, British, you name it.

https://www.sheldonbrown.com/cribsheet-bottombrackets.html
Alpinestars will use BSA threads:

Non- drive side (adjustable, with lockring) is right hand thread.

Drive-side (fixed cup, usually with a flange) is left-hand thread.

 

[FluffyChicken]

When it comes to getting a new one. The 7 means 73mm shell.
The NL in Shimano cartridge terms means 122.5 mm axle length as the replacement.

YST that just YST manufacturing it.


(Being 73mm means it has to be a correct threading, you can also follow the threads you can see to see how it unwind).

 

[Tootyred]

Im with @27motorhead if you dont have a length of stud you can use any big old long hairy bolt and a couple of nuts and washers.... go look in that old jam jar on the shelf!

Just remember you might need to lock a couple of nuts pinched together as a stopper, as on this side, turning it anticlock will also undo your nuts!

 

[27motorhead]

big old long hairy bolt and a couple of nuts and washers.... go look in that old jam jar on the shelf!

What you wrote took me back to going out into my grandads garage...

How many old sheds/garages had random stuff in jam jars with the lids nailed to the underside of the shelf?!*

 

[Tootyred]

Its a nice idea, but one misguided hammer swing or bit flying off the grinder and its a big "strike!"......and down they come.