chain checker?

young Ed

Veteran
right, i have decided a chain checker would be good to keep nice bike in good nick :smile:
so the question is what one and how the hell do i use it? parktools?
Cheers Ed
 
Location
Loch side.
Just use a 12 inch ruler. Get the ParkTool one and modify it according to the thread I posted some weeks back. All commercial chain checkers are flawed.
 
OP
young Ed

young Ed

Veteran
Just use a 12 inch ruler. Get the ParkTool one and modify it according to the thread I posted some weeks back. All commercial chain checkers are flawed.
interesting, have you got a link to the thread or can you remember what it was called?
Cheers Ed
 

ColinJ

Puzzle game developer
I just bought a steel rule on eBay for a couple of pounds.

The only problem was that they posted it in a plastic bag and the postman bent it! (I managed to get it pretty straight again but I left feedback suggesting that they use stiff cardboard next time!)
 
OP
young Ed

young Ed

Veteran
got plenty of 12 inch steel rulers but not a clue how to use one to check the chain stretch/wear?
Cheers Ed
 

ColinJ

Puzzle game developer
got plenty of 12 inch steel rulers but not a clue how to use one to check the chain stretch/wear?
Cheers Ed
Sheldon Brown page on chains.
Sheldon Brown said:
The standard way to measure chain wear is with a ruler or steel tape measure. This can be done without removing the chain from the bicycle. The normal technique is to measure a one-foot length, placing an inch mark of the ruler at the side of one link pin, then looking at the corresponding link pin 12 complete links away. On a new, unworn chain, this link pin will also line up exactly with an inch mark. With a worn chain, the link pin will be past the inch mark. [For accurate measurement, the chain should be held under some tension -- either on the bicycle, or hanging. Also, use a metal ruler or tape measure. Wood, plastic and cloth all can expand or shrink.-- John Allen]

This gives a direct measurement of the wear to the chain, and an indirect measurement of the wear to the sprockets. first, let's look at how to do this with a ruler that measures in inches.
  • If the link pin is less than 1/16" past the mark, all is well.
  • If the link pin is 1/16" past the mark, you should replace the chain, but the sprockets are probably undamaged.
  • If the link pin is 1/8" past the mark, you have left it too long, and the sprockets (at least the favorite ones) will be too badly worn. If you replace a chain at the 1/8" point, without replacing the sprockets, it may run OK and not skip, but the worn sprockets will cause the new chain to wear much faster than it should, until it catches up with the wear state of the sprockets.
  • If the link pin is past the 1/8" mark, a new chain will almost certainly skip on the worn sprockets, especially the smaller ones.
Obviously it is easier to measure how much longer the chain has become if the ruler is longer than 12"! I bought a 24" ruler.

My steel rule(r) has markings for 1/8", 1/16" and 1/32" which makes it easy to get an accurate measure of wear.

Looking at the video that Adrian just posted while I was posting ... I found it easier to measure from the left edges of the pins rather than guessing where the centres of the pins were.
 
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I'm window shopping for one of these too.

My current fav is the Birzman, mostly on price. Ebay has a number of Taiwan vendors selling the KMC one very cheaply.

http://www.birzman.com/products.php?src=prod&prod_sn=93

I went along to a basic cycle maintenance course the other day. The instructor there, who appeared to have a current or past career as a cycle mechanic in professional cycle racing was using the new Park Tools one CC-2.

http://www.parktool.com/product/chain-checker-cc-2
 

bpsmith

Veteran
I have the Park CC-2. Some people rate the steel rule, some like the checkers. I prefer the latter. The only downside to the matter is that there is potential to change the chain slightly early. No other negative. In saying that, it's down to how hard the user pushes the pins apart. Personally, I drop the pins in and measure when they just hit tension, which equates to using a steel rule basically, but far easier to read in the scale. Great tool, as always from Park.
 
OP
young Ed

young Ed

Veteran
thanks all! when i get a spare moment i will have a looks at all you links and properly compare steel rules and chain checker tools now i now a bit more about them
Cheers Ed
 

I like Skol

I don't think so, sonny!....
Location
Room 237
Ed, Don't get too hung up on the issue of inaccurate chain wear measurement. I use a 'wrong' type like THIS and although I know it may exaggerate the measured wear by shifting the rollers in opposite directions, it does still give a valuable indication of chain wear as I know a new chain won't fit the gauge. If I fit a new chain at the 0.75% mark there is a good chance it will still run on the old cassette. If I don't catch it before the 1.0% wear is indicated there is almost no hope of swapping chains and re-using the old cassette. Does this make the tool useless and its measures irrelevant? I think it is better than no tool at all. Incidentally, even at 1% and over the drive train still appears to work smoothly and will give many more miles of service, just don't expect to re-use any of the components when the chain is replaced.
 

runner

Veteran
Location
Bristol
I live some 200 yards from my LBS and would class myself one of their regulars...I tend to drop in from time to time to have the chain checked....the only problem is if I leave for too long then the cogs will need changed as well. I have been caught on this on a number of occasion and usually when you feel gear shifting "slipping" it is too late to save the cogs...So in short I do like that park tool cc2 and will prob order one, a nice simple precision bit of engineering in a digital obsessed era....
 
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