Eyes Roll

Hello Gurus, my 1980-90s Schwinn World Sport bike's chain is rubbing the front derailleur, slightly and intermittently, and that rubbing noise is bothering me, on my bike rides. I tried to fix the rubbing noise by rotating the limit screws, unsuccessfully. Then I noticed a slight play in the crank arm, and then also noticed the bottom bracket is out by a few threads, which could be the reason for the rubbing noise.

From the below pictures, does my bottom bracket, on the drivetrain side, need to be tightened? Is that possibly the reason for the chain rubbing the front derailleur? If so, how do I tighten the bottom bracket? I do not have any special tool for the bike bottom bracket, but I do have all kinds wrenches, screw drivers, and a mechanical toolset that I use to do repairs to my car.

Thank you in advance for any advice and help. 🙏

TenGrainBread 

You can see the cup has wrench flats. If you can get a wrench in there without removing the drive side crankset you could probably tighten it down with a large adjustable wrench. Keep in mind on this frame the drive side cup will have left-hand threads, so go counter-clockwise to tighten.

However based on the photos the drivetrain does really need a disassembly, cleaning, re-packing with grease, and re-assembly. For this you will need a crank puller to pull the cranks off the bottom bracket spindle, and a hooked spanner for removing the non-driveside bottom bracket lockring. Both bicycle-specific tools unfortunately.

If you don't do this, you run the risk of ruining your bottom bracket bearings and cups, which will be a more expensive repair than simple disassembly and cleaning of your existing BB. If there is a bike coop nearby you can borrow the tools mentioned above and look up the Park Tools video on bottom bracket install and removal. Otherwise please bring it to a bike shop for service.

On a separate note, there is some rust on the frame that you should remove. And PLEASE spray some lubricant into the bottle bosses on the downtube and plug them with the appropriate M5 or M6 bolt. Letting the internal and external rust continue will eventually cause the tubes to fracture which could result in a catastrophic road accident.
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3alarmer

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...yes, you shouldn't see any exposed threads like you have. But just tightening it without disassembly and service is a bad idea, because the bearing clearance in the BB is set from the other side (the adjustable cup.) No, there's no way to do this without at least a couple of special bicycle tools.

Eyes Roll

Thank you for your reply. 🙏

The last 4 pictures I posted were taken when the bike was turned upside-down; should I try to go counter-clockwise with a large adjustable wrench, when the bike is turned upside-down?

Thank you for your reply. 🙏

The bike rides like a champ though. It is a super fast bike. I have just repacked the ball bearings (10 on each side) and grease in the front wheel hub, and replaced gear and brake cables and casings, just last week. I will slowly buy the required tools and work on the bottom bracket when I find time.

By the way, I am planning to go on a 70-mile ride, tomorrow. Is it OK for me to go on the ride, tomorrow? Or will the bottom bracket loosen further and come off as I continue to ride without doing the proper fix?

madpogue 

That's called the fixed cup. Is the bottom bracket REALLY loose, left-to-right? If not, you probably won't be able to tighten down the fixed cup anyway, because unless there's a LOT of left-right play, then the adjustable cup (non-drive side) is probably threaded too far in. So yeah, as dsecribed above, you'd be wise to open it up and re-lubricate it anyway, and put it back together properly.

dedhed

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MeadMan2

Ride 70 miles with the fixed cup that far out and the complete bottom bracket will more likely than not be destroyed.

Eyes Roll

Not really, the play in the pedals is barely noticeable. I wouldn't even have paid attention to the pedals/cranks and the bottom bracket, if the limit screws did the trick and eliminated the rubbing noise. About a year ago, I had a similar chain rubbing noise to the front derailleur and turning one of the limit screws (was it a L limit screw? I do not recall,exactly) eliminated the rubbing noise. Then I replaced the gear cables and casings just last week, and the chain rubbing noise started again.

Thank you. 🙏

Thank you. 🙏

There's a good chance I am riding this bike with the bottom bracket in this shape for about an year already.

P.S. Bought this vintage Schwinn bike from an old man for $65, last year, and have been riding it since. As I said the bike rides great. I am planning to clean it up and paint the bike when I find time, since I like this bike, very much.

Thank you. 🙏

abdon 

Why are you even posting? If as you say you have a large enough wrench it would have been faster to pull the crank and tighten that.

The ball bearings work by riding around against the race. With the cup not holding them against the race they are all over the place. Allow a big enough gap and instead of chasing each other they'll start doubling up, allowing the spindle to to twist down

Steel1

Can a cup get that far loose without bearings falling out of place? Could the spindle be wrong width?

abdon 

Nope, that's what I just said. Once balls start pilling up sideways the spindle is no longer supported on both side, with forces twisting and ruining the cups.

merziac

Sure, without special tools, this is how that turns out.

Simply asking that question says it all.

Eyes Roll

When I started this thread, I thought it would be a simple and quick repair by threading in the bottom bracket.

Buying (ordering online and getting them delivered) specific tools takes a few days at least. As I said, I have decided to go on a 70-mile ride tomorrow either on this great gear bike, or on my single speed/fixie bike. I prefer to go on the ride on this bike; hence, I am looking for a quick fix, with the tools I already have with me now.

Thank you everyone for your replies. 🙏

By the way, I am planning to order these two tools 👇 (to use for this bike and two other bikes I own). I am thinking of avoiding to order a hook spanner, since a screw driver and hammer can do the same job that a hook spanner does.

https://www.amazon.com/Oumers-Bike-C...6040724&sr=8-2

https://www.amazon.com/109916-HCW-4-...00AOA2G8&psc=1

What other tools do I need to order? Please post the links of the specific tools I would need to remove and repack my bottom bracket. Thank you.🙏

Steel1

Looks like you are on right track. I would not ride until getting it straightened out, because something is very wonky.

HCW-4 is good for drive side (side with chain).

I use HCW-5 for non-drive side.

I think your crank arm puller will work, although I use a Park tool. Mine is CCP-1, looks same as Amazon CCP-22.

merziac

If you think a hammer and screwdriver will do, you are confused, if you don't have the correct tools when you need them then you will have problems just as you are now.

The fixed cup needs to be tightened completely then the NDS, other side cup and lockring are carefully adjusted and tightened to hold the correct preload when done properly.

This is only achieved with good tools, lockring and pin spanner used well and takes practice.

Do not skimp or cheap out, when parts are stuck and you are learning, good tools can save you from yourself.

Tools are cheap, good ones are worth it as they can last a lifetime and save headaches for being able to get the job done when the going gets tough.

I would encourage you to find a good condition Sugino set, I have these, Campy and Park in multiples, the Sugino's have served the best for 50 years.

Eyes Roll

You never tried any of these methods 👇, on the non-drive side?

abdon 

I was going to say more but I give up. The only good news here is that bottom brackets are cheap.

merziac

I guess all you really need is a hammer, screwdriver, vice grips and a fit all, guess I've been doing it all wrong for a long time.

jdawginsc 

The good news is that if you order the proper tools now, you will save a ton of money later.

I would not ride on this bike until you get the BB area sorted out.

If in a hurry, a nearby bike co-op will likely help you do it cheaply (maybe a donation).

A 12”-15” adjustable can be used for the DS fixed cup, but a spanner is better.

Lockring tool, pin spanner, crank extractor tool, 15mm socket wrench will get you there.

jdawginsc 

https://www.ebay.com/itm/28452763277...Bk9SR6yV8d3cYg

This would be a good start at a reasonable price.

brewerkz 

Service it, but probably a candidate for a sealed BB replacement, much less maintenance required.

Chuck M 

I zoomed in on the first picture posted, and it looks like the fixed cup may be cross threaded. I suspect the inside of that bottom bracket may hold a lot of surprises. I would plan on fixing it over planning a 70 mile ride on it.

SJX426 

[MENTION=542515]Eyes Roll[/MENTION] - There is no quick fix
1. disassemble
2. Clean, clean clean clean.
3. Inspect for damage
4. Either reassemble or replace with new BB.

I would be surprised if any of the BB parts are not damaged. These pictures look like it has been in this condition for a long time. It also looks like the last assembly steps were done in reverse, look how close the NDS crank arm is to the BB shell. That just doesn't look right.
This is all based on the assumption the BB is the right size for the shell, 68 vs. 70.
The fixed cup needs to be really tight which necessitates not having the DS crank installed and would be even better if the spindle and bearings were not install yet..

The videos presented using a vice grip is very disturbing. Why would anyone intentionally damage parts unless they were going to discard them? A lot of lock rings are chrome plated. Using plyers or vice grips will break the chrome plating with a result of more rust. Given the amount of dirt, it is inevitable.

Eyes Roll

There's a good chance that the ball bearings in my bottom bracket will be caged bearings. I have done some research by myself. My Schwinn World Sport's bottom bracket parts will more or less look like the five parts on the left side of the spindle (plus the dust shield, which is missing in the picture posted below).

dedhed

https://www.instructables.com/DIY-Lockring-Pliers/