Bicycle Mechanics - Newbie Help

Hi,

My bike is needing a clean and I've been searching around for a way to clean the chain. It looks like this is a widely discussed subject around here.

Thing is, I think I might be needing a new chain soon (I think I've done nearly 1000 miles) because it keeps skipping over when under load - a problem that's getting a lot worse, it doesn't take a lot of load to skip now. It does this mostly in the higher gears where I spend most my cycling time. Would I be right in thinking that the chain might have stretched??

Please excuse my ignorance, I'm a complete newbie.

As for the cleaning of the current chain... would just using a rag soaking in paint thinner and running the chain through it tide me over til I get a new chain (if I need one)???

Cheers.

ps. I don't know if it's relevant but I cycle in all weather.

Chains don't actually stretch. The holes in the bushings and side plates wear and become elongated, causing the chain to get physically longer. The fact that you cycle in all types of weather can accelerate the process because of the grit that will kick up off of wet sufaces. I would suggest cleaning the chain with a solvent on a rag, followed by a fresh application of a good chain lube- Finish Line, TriFlow, etc. Stay away from WD40, which is also a solvent, not a lube. If the chain still skips when it is clean, check the cogs for worn or bent teeth. If that is fine, replace the chain.

Hi,

My bike is needing a clean and I've been searching around for a way to clean the chain. It looks like this is a widely discussed subject around here.

Thing is, I think I might be needing a new chain soon (I think I've done nearly 1000 miles) because it keeps skipping over when under load - a problem that's getting a lot worse, it doesn't take a lot of load to skip now. It does this mostly in the higher gears where I spend most my cycling time. Would I be right in thinking that the chain might have stretched??

Please excuse my ignorance, I'm a complete newbie.

As for the cleaning of the current chain... would just using a rag soaking in paint thinner and running the chain through it tide me over til I get a new chain (if I need one)???

Cheers.

ps. I don't know if it's relevant but I cycle in all weather. A good maiintenance book would be a place to start. Also a visit to the repair section at www.parktool.com. A skipping chain can be worn chain, worn cassette, or both. It can also be derailer adjustment. Also learn to measure a chain for wear. New ones are exactly 12" long in a foot of tensioned cahin,c-c of pins. Toss it when it measures 12 1/16". Running a too worn chain trashes the cassette too. If you havent cleaned and lubed the chain in 1000 miles it and the casette could be trash. Properly maintained chains can go many K miles without damaging the cassette.

When a chain wears out, it may wear the cogs into a "sharks tooth" profile. They will work together without skipping. When you fit a new chain to worn cogs, the chain will slip over the worn cogs one tooth, when you pedal hard. You then need a new cogset.
What type of "skipping" is your chain doing?

As an all-weather rider, you should be using mudguards, and re-lube the chain every week, and after heavy rain.
Be careful with solvents, they can get into the wheel and bottom bracket bearings and dissolve grease.

Thanks folks.

I think I'll follow demoncyclist's plan for starters. Clean, lube and then see how things run. Erm, another stupid question... what's the cassette?? (Damn, I really hate it when I'm only just getting into something and I sound like a fool). Are there any decent sites that explain stuff like this to beginners? All I could find anywhere were sites that assume a certain level of knowledge.

A book would be a good idea. Any suggestions?

Oh, and I forgot to ask before... about how much should I expect to pay for a new chain?

Thanks again.

The cassette is the set of gears mounted to the rear wheel. As for chains, I usually use a SRAM PC68 for my 8 speed Campagnolo drivetrain. If you have a 9 speed setup, the PC69 is a good choice. Either should be $20-25. A good book, highly recommended round here is "Zinn and the Art of Biicycle Maintenance" Good luck!!!

Are there any decent sites that explain stuff like this to beginners? All I could find anywhere were sites that assume a certain level of knowledge.


www.sheldonbrown.com is a great reference site.

Click here (http://www.sheldonbrown.com/glossary.html) for a link to his glossary page - very useful for definitions/terms etc.

Actually, chains do stretch.


The holes in the bushings and side plates wear and become elongated, causing the chain to get physically longer. Very true. Therefore:

The LINKS don't stretch. The CHAIN, since it has become physically longer, has by definition (Websters), stretched.

Websters:
stretch
v. stretched, stretch·ing, stretch·es
v. intr.
To become lengthened, widened, or distended.

I try to impart some knowledge, and it turns into a discussion about semantics, or in this case, some antics. I don't think Webster had a bike.

Don't bother cleaning the old chain. Just buy a new one and give it a try.

I've always used 1% as the wear limit, or 1/8" over 12 inches. Thought that's what the manufacturers recommended as the limit. Wouldn't hurt to change at 1/16 of course; I just like to get the wear out of stuff before throwing it away.

I've always used 1% as the wear limit, or 1/8" over 12 inches. Thought that's what the manufacturers recommended as the limit. Wouldn't hurt to change at 1/16 of course; I just like to get the wear out of stuff before throwing it away. 1/8" often trashes the cassete.That's throwing money away too.

1/8" often trashes the cassete.That's throwing money away too.

Guess our experience varies. I've never seen much cassette wear at all with Ultegra, at least from looking at the cogs, or doing a "static" load inspection to see if the teeth stay engaged. IMO, even a 1% chain elongation wouldn't mean very much to the mesh with cog profiles....but's that just opinion of course based on limited experience.

The alloy chainrings seem to wear much faster for me than the cogs. On my old bike now, I've got worn chainrings, with the chain at about 1/16" elongation. Only the top 3-4 teeth are pulling the chain under load. The chain would have to be really worn to fit these rings.

Thanks for all the help.

How would I tell if my cassette was trashed??

You put a new chain on it and nothing changes... :)

I recently experienced skipping on a relatively new chain that didn't measure out with any wear. The crank & cog teeth were also in good shape. On close examination the chain had some twisted links. It was an inexpensive chain I put on one of my rain bikes. Don

You put a new chain on it and nothing changes... :)

lol, fair enough. :rolleyes: If it was trashed wouldn't that damage the new chain, or would the damage by the time I noticed be minimal? I guess I'd know pretty quickly so I suppose it wouldn't make too much difference.

Also, just noticed on my way to work, my derailer is slightly bent (don't know how that happened or how I haven't noticed til now but, alas, it always seems to do that), should I have a go at repairing it myself or should I just take it in to the shop for that? I would need a particular tool for that, wouldn't I? What are the chances I'd do more damage than good?

If you put on the new chain and select a gear at the rear that allows for the straightest chain line and it still skips then I would say that the teeth on your chainring are worn (Only saying this if the chainring *one at the crank end* is made from alloy) But, considering you said its done 1000 miles I find it unlikely. So new chain on, select a gear that affords the straightest chain line and pedal. No jumping problem solved, jumping... I don't know :)

As for the rear deralier (thats not how its spelt, but cant for the life of me remeber, hehe) It can be out a little and give changing problems. The bike shop will have some fangled gadget that will see how bad it is by magnifying the problem.

Try the chain first (only a few quid) then look for wear on teeth (usually sharp looking teeth i.e. they have points at the tip rather than about 2~3mm that should fill the space between the chain pins without too much play) If its a cheap bike it should still last a lot longer than 1000 miles unless of course you ride it on the beach :)

Hope this helps

Trash it.

Chains are cheap and go with the SRAM for your application because of the Power Link that makes off the bike chain cleaning a breeze. Not tools required for removal.

Hit your local Home Depot, Lowes, or even WalMart and pick up a gallon of mineral spirits for chain cleaning. It's good to wipe down your chain about every 3 - 5 rides (depending on weather conditions) with a dry cloth and then reapply lube.

I am really impressed with a product line called "Rock and Roll Lubricants." www.rocklube.com I've been using their chain lube for 3 years after trying all the hype brands. They have a full line of products that rival most of the major brands found in shops and catalogues. I use the "Gold" wet lube and as directed, wipe the chain with a clean rag, apply lube, wait 30-seconds and wipe off all the liquid left on the chain. The lube only does the chain good in the rollers and between the plates, not on the outside. This only attracts dirt which leads to early chain failure. I clean my chain about every 5th ride and floss the cassette with an old t-shirt. By keeping the black gunk off, you rarely have to clean the chain with cleaners or solvents.

Marc

I Cleaned up the chain a little yesterday just with some paint thinner soaked in a rag. The whole lot still needs to get a really good clean though. Anyhow, it's working a treat now, I used some white lightning lube I got at the local bike shop, nothing skips and everything looks good.

It must have been really gunged up to be as bad as it was. I still might invest in a SRAM chain for easy (proper) cleaning purposes.

Cheers folks.