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was going to put a add up in the wanted for some chainrings but im not sure what rings im looking for. the bike is a marin.not sure what year
anyway my lad said it maybe be better to ask for some crack arms with the rings on is this right ???
It all depends on what crank you have, when you look at the centre of the rings from the side, does it have a hole going through, or is there a allen bolt?
There are some pretty good deals at the moment for cranks, but bear in mind you'll more thank likely have to replace the chain and cassete too.
You could get a Deore level crank, BB cassete and chain for around £100 from Merlin cycles.
I have sorted some photos hope this will help. yes there is a allen bolt in the middle. crank arm center of peddal to center allen bolt is 170mm
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atb
Those are standard 64/104mm rings by the looks of things. Something like Deore rings are cheap and will last well. New cranks and BB would probably be more cost effective, but on the assumption you don't have the two sets of tools needed to change that benefit is somewhat eroded!
A quick glance suggest you'll get rings (shimano deore) for between £30-40 and a new deore M590 crankset (with BB) for just under £50 from Rosebikes, so there not a lot in it. Though as Njee say you'll also need the tools for both to remove/fit them.
As above there a good chance you'll need to (or should) replace the cassette and chain at the same time too, otherwise your new rings will wear quickly due to the old chain.
thanks alot for the replys