Measuring cranks

jon_g

need some help please! i've got an old Bridgestone RB bike as my winter hack, and i've just realised i threaded in the left hand peddle skew, so it's ruined the 'proper' thread. Obviously i cant ride it like that. so i either need to replace justr the left hand crank or the whole crank. the whole point of me having this bike was to save money and not have to ride my 'race' bike though winter so ideally i dont really want to spend too much on it. What i'm trying to find out is, when measuring a crank, do you measure the entire length of the crank (doesnt seem right, way too long!) or from the centre of where the 2 bolts are (ie from centre of where the crank attaches to the bottom bracket to the centre of the peddle 'hole')?? or from edge of each 'hole'??



also, i've been looking on ebay for cranksets, if i was to replace the whole thing, is that something i would be able to do myself? (not very technically capable, dont want to ruin it!)



thanks for any help!

TommiTri

from the centre of the bolt attaching to bb to centre of where pedal spindle attaches. Sorry I'm not too good on the lingo!

jon_g

cool, thanks Tommi, thats what i thought (and i dont know the lingo eitherwarbling on!)

treefrog

Get a dye and rethread it. I have never done it myself but I've seen an engineer friend do it

aero blob

Cheapest way is definitely pop it into your bike shop. They can remove the pedal, rethread the crank with something called a helicoil and it should cost no more than a tenner!



You could of course buy a replacement chainset. You need to be sure its compatible with your bottom bracket and your chain (in terms of number of gears etc as this determines chain width). If you replace your chainset you will need the correct tools too and its also a good idea to replace the Bottom Bracket at the same time anyway - saves more work later on. If you want to save dosh - go for the first option! Best wishes. Andy