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Hi all,
40 miles into the Sarn Helen sportif on Sunday, my left hand crank bolt decided to loosen its self, and after about 7 miles of screwing it back in by hand every 5 mins (then 1 miles of one leg pedaling when it finally fell out and I couldn't find it) I reached then lunch stop and could be rescued by the support van. It's a square tapered jobby, and a guy on the ride said that once it's loosened once, it'll keep on coming loose. I could just look for a replacement left crank arm (it looks quite worn now around the square hole, from riding with it loose), but will the bottom bracket be knackered as well?
The bike is actually a strange mix of half decent components and some fairly shoddy looking stuff that I think came off an Apollo of some sort (the chainset being in the latter category), and I was thinking of changing this anyway. At the moment it has a 105 front mech, tiagra rear mech, 8 speed cassette, sora flight deck shifters, double chainset of dubious origin and unknown square tapered bottom bracket.
Would I be making much weight saving by upgrading the chainset/bb to something like a hollowtech or octalink? I've seen a 105 octalink chainset on CRC for £30 in the sale, but it says it's 9 speed, so would that not work with the rest of the kit? I don't have money to burn, so don't think I could afford to change the cassette and shifters to 9 speed too. Anything I buy is either going to be second hand or in the sale to be honest.
Any advice on my options greatly appreciated. Thanks!
The 9 speed crankset should work fine with an 8 speed chain over the top of it.
[url= http://www.singletrackworld.com/forum/topic/how-do-9-speed-chainsets-work-with-8-speed-everything-else ]See here[/url]
I'm running a 9-speed Ultegra chainset with 8-speed rear end - no problems at all. I also have a bike with 9-speed cassette using a chainset which came on a 7-speed bike which works fine. Chainsets don't tend to care too much how many gears you have on the back - only when you get to 10 is it sometimes an issue (but not necessarily even then).
That crank is almost certainly shot, though the BB should still be OK. Depends what you have whether you'll save any weight upgrading - some ST cranks are just as light as more modern ones (and some modern ones aren't all that light).
FFS, 2 weeks on holiday and the first thing i see is a "darkside" thread, its called road cycling, nothing dark about it, call it by its name.....
OK, off for a coffee now
tragically1969, sorry, was just keeping with the terminology that seems to be used here, didn't mean to offend! It is a mtb site after all, and if we really thought road riding was that dark we wouldn't be posting about it.
Edit: hope you enjoyed your hols!
weight saving will deemed on whatwmt have just now. don't forget cost of new bb.
but will the bottom bracket be knackered as well?
Unlikely
Would I be making much weight saving by upgrading the chainset/bb
1-200g at a VERY rough guess if you get something half decent like a Tiagra HT2 chainset or the 105 you mentioned
so would that not work with the rest of the kit?
9 speed will be fine (but your chain may be worn enough that it'll slip on new chainrings)
No need to apologise, you are forgiven......just dont do it again... 😆
I could think of things much darker than road bikes...
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Omnomnomnom