Wilsons Sandbox

Listers, I was able to put a little time this afternoon into a fun shop project. It's still kind of hush hush so I won't go into it here. But it did involve an old used stock KLR650 chain that had been on the shelf for a few years. I had to break a few links to change it's size. What I found on the third link I took off was some rust and a very worn pin. This is the pin that holds the entire link together. If you look at a stock chain on a KLR the ends are visible on the outside of each link. I took the time to measure the pin in two orientations and then compared the measurements with the pin next to the worn one. Let's call the orientations X and Y for ease of discussion. The X and Y are 90 degrees apart. Here's what I measured. Bad Pin Good Pin X 0.187" 0.206" Y 0.205" 0.206" The inside of the roller on the bad pin was badly deformed and rusted in the same orientation as the worn pin. The o-rings looked ok when I took the link apart. At least the o-rings looked the same as on the good pin. I checked a few more links for sideways movement just to see if I could tell a difference. It was obvious there are a few other links that are also well worn. And it didn't seem like there was any rhyme or reason to where the links showed up as bad. I don't positively remember the history of that chain but I think it was from Steve Rankin's bike with probably 27,862 miles on it back in 2004 when we were getting ready for the Great Divide Ride. If I recall correctly he put my stock 3,200 mile chain and rear sprocket on his bike for the ride. That might have been the original chain on that bike. I don't know how he maintained it but knowing he bought the bike with about 19,000 miles on it whatever happened to the chain happened over a long time. Just found that kind of interesting and thought you might too. Best, Jeff Saline ABC # 4412 South Dakota Airmarshal Airheads Beemer Club www.airheads.org The Beautiful Black Hills of South Dakota 75 R90/6, 03 KLR650, 79 R100RT

I'm not a "chain guru" but what I've read is that the pin is fairly soft metal. They are not supposed to be hardened. Obviously wear is going to happen. It is possible that this is a normal wear pattern; pins getting worn down. If I read it right, this chain had a lot of miles!

--- In DSN_KLR650@yahoogroups.com, Jeff Saline wrote: >

On Thu, 08 Nov 2007 17:30:07 -0000 "mikeypep" writes:

> I'm not a "chain guru" but what I've read is that the pin is fairly > soft metal. They are not supposed to be hardened. Obviously wear is > > going to happen. It is possible that this is a normal wear pattern; > > pins getting worn down. If I read it right, this chain had a lot of > > miles!

<><><><><><><> <><><><><><><> Mike??, You're right the chain did have a lot of miles. I just thought it was interesting that pins about 5/8" from each other would have such different wear. The "good" pin was still round while the worn pin was close to the same diameter on one axis and worn out on the other axis. I believe these pins are hardened a bit. Not enough to become brittle but lots harder than a grade 8 bolt. I used a punch on the end of another pin to see if I could peen it a bit. All it did was flatten the end of the punch. I wonder if Eagle Mike has ever done a hardness test on a chain link. Mike??? Best, Jeff Saline ABC # 4412 South Dakota Airmarshal Airheads Beemer Club www.airheads.org The Beautiful Black Hills of South Dakota 75 R90/6, 03 KLR650, 79 R100RT

That was really interesting, Jeff. Not real confidence inspiring, eh? I guess it backs up why we get 'tight and loose spots' in chains as they wear. No real rhyme or reason, it would seem like they'd wear similarly. I know when I've been trying to establish how much my chain has "stretched", and I measure a 10-link section with a dial caliper, I have to measure a number of sections before I find the longest one. Interesting. Bill Watson phoenix, AZ __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com [Non-text portions of this message have been removed]