I got my current MTB in March and it was fitted with a KMC chain. Afer the first few rides on it I started breaking the chain over a few rides, sometimes multiple breakages per ride, so I decided to change the chain and went for a SRAM chain, since my other drivetrain components are SRAM. I didn’t go for the ultra lightweight racing chains with hollow links, or the cheapest chains, I went for a mid range Nickel coated ‘bog standard’ chain. This has stopped the breakages, however, after starting to get chain suck i’ve just measured the chain stretch and bu**er me, the chain is due for replacement! I’m pretty mechanically sympathetic to my equipment, so i’m not one of those who tries to ram the chain up the block while under full load on a steep climb, I clean and lube after every ride pretty religously, so i’m somewhat surprised at the short space of time for the chain to stretch/wear. I’m not sure how many miles i’ve got on this chain, but i’d be very surprised if it is much more than about 50 to 60 on cross country style riding.

What is the average expected life of a SRAM chain for XC riding? I have been using WD40 dry lube to lube the chain, which seems to be effective in terms of quietening down the drivetrain noise, but maybe its not as good as normal wet lube?

1000+ on my last one. Also using only WD-40 or GT-85 as lube.

Never actually took it off for any other reason that i’d ‘broken’ the chain so many times splitting it to try different chainguides.

if you put a new chain on an old block, the new chain will have had to stretch to mate with the worn teeth of the old block. Havig done that, then it will probably chunter along ok I guess for quite a while.

When I used to run gears, I never measured a chain for stretch. Id swap three chains on to one block in rotation and when they all looked fecked, get a new block & three chains.

I have been using WD40 to lube the chain

Fail.

(I love forum hand grenades).

Was there an edit in the OP, or are you paraphrasing (wrongly)?

You’ve had the bike 9 months, the chain started breaking after ‘a few rides’ so you replaced it and have now only done 50-60 miles?

I find my chains need replacing every 3 months of riding once a week if I follow the chain checkers.

OK, i’ve used WD40 Dry Lube to lube the chain which is specifically for the purpose of lubricating bike and motorbike chains and gears, not the usual WD40 stuff, but either way it might be struggling to cope.

I’ve got a replacement chain (same as the previous one) but the bike was new in March so I really doubt the block and chainrings are worn, unless the WD40 Dry Lube is not man enough for the job then it may have worn the entire lot. I’ll take a look for block and chainring wear.

Std WD40 is not meant for lubricating chains. It is meant to disperse water. WD40 have moved in to the chain lube market I believe but I have not used the WD40 chain lube. Edit: I see that you are using the pucker stuff.

Chain life will depend on more than just the lube used. Where, conditions, maintenance etc will all play a part in the life of the chain. How long is a piece of string?

I used to make a note of when I changed chains and a PC-850 lasted at least three times as long as a PC-830. I use PC-870’s now which seem to be a bit better giving me around 9 months of riding twice a week. In fairly clean conditions, using Rock n Roll Extreme for cleaning/lubing.

As above, there a lot of variables to consider…

Interesting you had failures with the KMC. Did you re-connect using a chain tool or the quick link widgets?

It was a strange thing with the original KMC chain. Everything was fine for about 5 or 6 rides, then I had a breakage every ride for about the next 5 or 6 rides. I re-connected the links myself, but each time it was a different link that failed, never the previously repaired link. In the end I used a quick link before deciding to change the chain. It just seemed that once it started to fail it was prone to it – totally illogical I know.

I’ll check the block and chain ring wear tonight and swap with the new chain and use a different lubricant and put this down to something strange.

Clean your drivetrain and chain regularly …and properly ..dry and re-lube …should last over 6 months regular riding …..def use a chain checker to avoid expensive drivetrain replacements …IMHO