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

[drexal77]

Hi all, sorry for the delay in replying. Thanks so much for all the awesome tips. Reading through them all i'm like "oh my god" that makes perfect sense about following the thread etc with the lock ring, why didn't i think of that!!!!! And thanks for the alpine stars BSA info & for the explaination of the markings on the spindle super interesting and so helpful. I'm going to save this whole thread as a PDF and save it into bottom bracket folder for the future as i have a pretty rusty old scott super america that has this same style BB so i'm sure i will run into issues with that one to. I've managed to find some old threaded rod, but sadly not enough nuts and no washer of the right size to protect the face of the cup, so will order all these up. Thanks so much again for all the help. This forum is awesome. Also love the images of the jam jars, oh to have a shed or room to be able to work on bikes and to store tools, hopefully one day. I just now need the family leave me a alone for a couple of hours so i can try and tackle this again once i've got all the parts needed. I'll follow up with some images once i get this little b*gger off.

 

[drexal77]

Hi all,

I'm back again already. I through i might quickly order new bearings and possibly new cages (although i prob don't need the cages) if i can source them. But i thought its prob best to ask your guys advice before i go blowing money when you all might say just replace. Its says on line if there is any pitting on the spindle races that you need to get rid of them. But i just wanted ask your guys advice first. Please see images below. I've listed all my questions as they is a few (sorry i know this must be annoying to experts on here, is the below is prob super simple and just common sense stuff).

0. Please see first image of the fixed side cage and bearings, there in pretty good condition. But the adjustable side (which is still stuck) the bearings are pretty pitted and have turned dark grey. Also please see image two. Again i think its the adjustable side the spindle is really quite bad when you do the ball point pen test, i have read you can clean this up with emery cloth, but i feel this has prob gone to far do agree?

Its annoying as the adjustable side is in good condition apart from one little notch in it. Also the fixed cup seems to have a crack or line running through the inside of it. When i was riding it, it didn't feel rough i only noticed something was wrong because it became loose.

1a. From seeing the images. Would you try and find replacement bearings and cages and just replace them and keep the current spindle?

1b. Or would you replace the bearings, cages and try and source a NOS spindle of right size? (which will prob be pretty tough to source).

1c. Or would you replace whole lot with a more modern cartridge style BB (I'm pretty sure i have a Tange Seiki LN-3922 that i think would fit this shell and just enjoy riding the bike again?
I did want to keep this bike fully original as i'm 99% sure this YST BB is the original that came with the bike from factory. But i don't think this bike will ever be restored to immaculate bike show quality so i'm not sure having the orginal BB would matter. Also i have read that the old cup and cone are pretty tricky to adjust perfectly with the pre-load etc, is this true? epecally for me being a notice etc. Could please ask what you guys would do?

2. It seems to also possibly have the orginal YST headset, would you (as intend to keep riding this bike if i can on w-ends etc) open up the headset and clean it all out & poss repalce bearing if needed before i ride it again, as if it is rusty inside like the BB was i'm probably damageing it?

3. If any of you say to source a NOS spindle etc and keep the original BB, do you all get your ball bearings from online or local bike shops? if you buy them online could recondement somewhere that sells these size bearings and cages, please see image 5, 6 & 7.

Thanks so much again to anyone that replies & can offer advice.

 

[FluffyChicken]

In the bin, or made in to something else. A crank holder or something.


Your choice to get a new cup/cone setup or use a cartridge. Cartridge is easier, but you then don't learn a new old (very old) skill.

Headset, clean, see if damaged, replace if needed.

----

I've ridden on damaged BBs, though nothing quite as bad as yours. A new bearing would be smacked to bits as it will be both too tight and too lose as it is rotated around the races. Even with a new spindle, the bearing will be damaged by the other race, that will then transfer over time to the nice new axle. Waste of money.


A headset is more forgiving, but still if you want to ride it and not get irritated at notches and it being stiff/rocking then just get a new one.
See if you can find something that looks similar.

 

[drexal77]

Thanks so much @FluffyChicken for super fast response, yes that all makes complete sense. Maybe i'll try and find a NOS stock YST or shimano similar (although these look super expensive) i'll poss keep an eye on ebay, as it would be awesome to learn the skill of fitting one of these, but i would service it every year so it lasts me hopefully rest of my riding days & obsessed with all things 90's so would love to keep it original. But maybe for now i'll just put in the cartridge just to get me back out on the road. And thanks for tip on the headset will take apart before i ride it again and hope that just need replacement bearing for that. Thanks again really appreciate your time in replying.

 

[Imlach]

Go for cartridge. Far less faff. Nobody checks the BB of your bike.

 

[bikeworkshop]

The original part is pretty basic quality and mashed, so there's no shame in upgrading - and if you've got a 73/122 bsa cartridge bb handy, then away you go

 

[27motorhead]

As @Imlach and @bikeworkshop both said, the simplest and most effective thing to do is fit a more modern Shimano cartridge BB. Cheap and simple and will spin lovely.

If you want to keep your bike as original as possible you can by all means buy some 1/4" loose balls...

I hate Amazon, but here's this:
https://www.amazon.co.uk/Weldtite-Precision-Ball-Bearings-Loose/dp/B00BJ3SATA
Anyway, buy some loose balls and grease up the cups and chuck them in. You should fit x2 more balls in each cup vs. when they are in cages. The BB will work, but looking at the state of the axle and surface of the cups it'll be pretty rough and you'll probably feel the roughness through the pedals (your pedals might be rough too!!!), plus I can almost guarantee it'll have loose/tight spots which means you'll have to adjust it so it spins OKish and will need further adjustment as it is used.

I've tidied up cups and axles using lathes and also can used valve grinding paste in with bearings for a week or two (all because I had them to hand, plus I was younger and had more time!).

So, the sensible fix is a Shimano cartridge or something similar, the retro grouch fix is loose balls and fiddling.

Ta!

 

[Imlach]

I run cup and cone on a few and I'm OK with it but for serious miles in mucky conditions there's absolutely zero benefit to them over a cartridge

 

[bikeworkshop]

I run cup and cone on a few and I'm OK with it but for serious miles in mucky conditions there's absolutely zero benefit to them over a cartridge

Although we've seen plenty of shimano 105 (and campag) Cup'n'cone with 10,000 miles on them, and few un52s gone at 2000, and cheap cartridge units knackeres in a few hundred miles

There aren't many decent cup and cones out there though.