It's time to buy a new chain. I bought a PC-971 chain and to my dismay, it's only lasted 800-900 miles and it's already stretched halfway to the .16'' mark. How much longer do you think my chain can last before I have to replace it?
This time around I'm probably going to buy the cheaper PC-951, but I'm wondering what the difference is. The specs say it's made of steel, so does it last longer than the nickel plated 971 and 991? Furthermore, WHY does the 991 cost $45?
EDIT: Also, this is my first time using a 9-speed system. Previously I've been riding on an 8-speed, and the current chain on the 8-speed shows no signs of stretch after 2200 miles. Do the thicker 8-speed chains last longer than the thinner 9-speed chains?
I guess I shouldn't complain though, I spend a lot less on my 9 speed than your 10 speed.:p
Your chain will probably last until it reachs the .16" mark? I can't really guesstimate this for you because I don't know how you ride, how much you ride, the conditions that you ride in, and how anal you are about chain lubrication.
That aside, I think that the only difference between the chains is the plating on the 971 and I think that the 991 has hollow pins to cut down weight. I was looking for chains last year and I beleive that this is what the differences were. I went with the PC-951 because I ride my bike rather than let it sit looking pretty, and I don't trust hollow pins for some reason. I don't race and that small added amount of weight is not a concern for me, at least not for more than double the price of the 951.
I can't answer the question concerning the 8-speed chain lasting longer. I have two 8-speed bikes, a nice garage queen road bike and a mountain bike. The road bike had about 800 miles on the old chain when I got her and I replaced it early because there was stiffness in it that I could not work out. The replacement chain has only been on it for about 600 miles. The mountain bike has the original chain but it does not get much use at all, about 100 miles a year and I am a lubricator. At least once a week and always if the chain gets wet. My 9-speed chains usually last 2000 - 2500 miles.
