This is long winded, but it is an earnest question for tool aficionados and people who like to save money on their equipment.
As you all know, as the chain wears, the pin to pin distance increases eroding the 1/2" pitch that the chain is supposed to have. When this happens, the gears wear down to match the chain. This is why we generally have to change the rings and cogs when we change the chain. An expensive proposition especially if you like high end equipment and/or have multiple bikes.
It is however possible to save the rings/cogs if one increases chain replacement frequency. Due to necessary fit tolerances, new chains do not immediately begin wearing down rings until a certain amount of "stretch" has occurred. The questions come down to:
"Where is the acceptable wear limit before gear damage occurs?"
"How do you measure this limit accurately?"
"Is the riding time it takes to reach that limit reasonable?"
So I've looked through the forums to see what people are using to check their chains for wear. The most common responses are using a Park, Shimano, Rohloff tool or a 12" ruler.
The dedicated Park/Shimano/Rohloff/etc tools seem to get a common complaint of relying on pushing the rollers against the pins which means the manufacturing tolerances of the roller to the pin directly affect the measurement. Indeed, some users report brand new chains as measuring half worn out or worse using some of these tools.
The 12" ruler, while of good intent, is difficult to accurately use and is therefore more of a rough estimate indicator rather than an accurate gauge of usable life left. I.E. your measurement is dependent on how still you can hold the ruler while applying tension to the chain and eyeballing the hash marks.
I bring all of this up because for the last 17+ years, I've been using a home-brewed tool to accurately determine the wear limit and reduce my ring replacement budget. In fact, the only times I've had to buy rings in the last 15 or so years is when upgrading entire drivetrains (like 8 to 9 speed, XT to XTR, Shimano to SRAM, etc) or when experimenting with where the wear limit is. No BS, I've got rings and cogs that have 5 years of hard riding on them with no hooking or chainsucking, and they still take new chains fine. For me, this tool is the single biggest money saver in my tool box.
So I've shown this tool to some close riding friends and some are very interested in getting one for themselves. I'm just curious if there's enough interest out there for me to get a production run going. I've already figured out the design for manufacturing and expect the cost to be $25 to $30 if bought from me directly. As a plus, I'll be building them in the US and not off-shoring it... not ever. If you are interested, please respond to this post. If I get 40 or so earnest responses, I'll hit the "go" button.
A few other notes:
The tool obviously does not function like the other tools, but is just as fast to apply and very accurate. It has been tested through dozens of chains of 7/8/9 speed Shimano/SRAM varieties. 10 speed has not been out long enough for me have any real data. I do expect the tool to work fine with it though.
With this tool, you can not only save on gear components, but you can also make objective quality/strength comparisons between chain models/brands and even chain lube. For instance, for me Sachs/SRAM PC58 and 68's (8 speed) had approximately the same wear quality clocking in at 16 months. A CN7701 XTR 9 speed chain has about 9 months of life. A SRAM PC970 (2005 model) lasted a measly one month. So this tells me that 8 speed is cheaper to own since mid range product lasts almost twice as long as the top of the line 9 speed chain. But if I want to run 9 speed (and I have been) then the XTR chain still saves me money in the long run.
Your figures will vary of course depending on your environment, riding style, riding frequency, lubricant choices, shifting style, body weight, etc. but you can determine trends using this tool. In other words, if you never lube your chain, are 300 pounds, cross chain all the time, and ride uphill 10 miles a day, you might find that replacing the drivetrain every six months is cheaper than replacing the chain every week.
If you got this far, thanks for your time and attention span. :thumbsup:
H
As you all know, as the chain wears, the pin to pin distance increases eroding the 1/2" pitch that the chain is supposed to have. When this happens, the gears wear down to match the chain. This is why we generally have to change the rings and cogs when we change the chain. An expensive proposition especially if you like high end equipment and/or have multiple bikes.
It is however possible to save the rings/cogs if one increases chain replacement frequency. Due to necessary fit tolerances, new chains do not immediately begin wearing down rings until a certain amount of "stretch" has occurred. The questions come down to:
"Where is the acceptable wear limit before gear damage occurs?"
"How do you measure this limit accurately?"
"Is the riding time it takes to reach that limit reasonable?"
So I've looked through the forums to see what people are using to check their chains for wear. The most common responses are using a Park, Shimano, Rohloff tool or a 12" ruler.
The dedicated Park/Shimano/Rohloff/etc tools seem to get a common complaint of relying on pushing the rollers against the pins which means the manufacturing tolerances of the roller to the pin directly affect the measurement. Indeed, some users report brand new chains as measuring half worn out or worse using some of these tools.
The 12" ruler, while of good intent, is difficult to accurately use and is therefore more of a rough estimate indicator rather than an accurate gauge of usable life left. I.E. your measurement is dependent on how still you can hold the ruler while applying tension to the chain and eyeballing the hash marks.
I bring all of this up because for the last 17+ years, I've been using a home-brewed tool to accurately determine the wear limit and reduce my ring replacement budget. In fact, the only times I've had to buy rings in the last 15 or so years is when upgrading entire drivetrains (like 8 to 9 speed, XT to XTR, Shimano to SRAM, etc) or when experimenting with where the wear limit is. No BS, I've got rings and cogs that have 5 years of hard riding on them with no hooking or chainsucking, and they still take new chains fine. For me, this tool is the single biggest money saver in my tool box.
So I've shown this tool to some close riding friends and some are very interested in getting one for themselves. I'm just curious if there's enough interest out there for me to get a production run going. I've already figured out the design for manufacturing and expect the cost to be $25 to $30 if bought from me directly. As a plus, I'll be building them in the US and not off-shoring it... not ever. If you are interested, please respond to this post. If I get 40 or so earnest responses, I'll hit the "go" button.
A few other notes:
The tool obviously does not function like the other tools, but is just as fast to apply and very accurate. It has been tested through dozens of chains of 7/8/9 speed Shimano/SRAM varieties. 10 speed has not been out long enough for me have any real data. I do expect the tool to work fine with it though.
With this tool, you can not only save on gear components, but you can also make objective quality/strength comparisons between chain models/brands and even chain lube. For instance, for me Sachs/SRAM PC58 and 68's (8 speed) had approximately the same wear quality clocking in at 16 months. A CN7701 XTR 9 speed chain has about 9 months of life. A SRAM PC970 (2005 model) lasted a measly one month. So this tells me that 8 speed is cheaper to own since mid range product lasts almost twice as long as the top of the line 9 speed chain. But if I want to run 9 speed (and I have been) then the XTR chain still saves me money in the long run.
Your figures will vary of course depending on your environment, riding style, riding frequency, lubricant choices, shifting style, body weight, etc. but you can determine trends using this tool. In other words, if you never lube your chain, are 300 pounds, cross chain all the time, and ride uphill 10 miles a day, you might find that replacing the drivetrain every six months is cheaper than replacing the chain every week.
If you got this far, thanks for your time and attention span. :thumbsup:
H
