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Determining Bent Cranks /Spider & Not True New Chain Rings

wolfsbane2kwolfsbane2k Posts: 3,037
edited July 2015 in The workshop
Following a crash a month ago where the two outer chain rings on my triple crankset MTB got a thump because my ankle got jammed between them and the car's wheel ( and I don't know what quite happened with the crank/pedal), I've had the bike "repaired" by the drivers shop where they bend the outer chain ring straight (despite being asked for a new ring) and put a new middle ring on, and stated "The cranks fine".

However, after riding it for a 2 miles, Its felt very odd and the middle ring can be seen to be wobbling all over the place, which for a brand new ring just isn't right. I've video'd the wobble, which clearly shows the spacing between rings changing, and the chain suddenly "kinking" on a specific tooth by the crank arm. I'm not sure if the kinking is a tooth/ramp to gear changing, but seems very odd.

Is there a specific way to determine if the cranks/spiders are bent and therefore should be replaced, vs just a poor fitment of the chainrings, possibly for the purpose of solicitors/insurance claims?

Because it's an insurance job, I'm likely to get into argument with someone over "proving the job wasn't done properly", as I'm thinking of taking to a different shop and getting the BB and crankset replaced, as they originally recommended

Thanks in advance,
Intent on Cycling Commuting on a budget, but keep on breaking/crashing/finding nice stuff to buy.
Bike 1 (Broken) - Bike 2(Borked) - Bike 3(broken spokes) - Bike 4( Needs Work) - Bike 5 (in bits) - Bike 6* ...


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