Basically my mate bought a new Renthal chain/sprockets for his 2008 CRF450 but; the chain is far too long for the standard size sprockets that came with the kit! We've had to take out 4 links for it to fit ??? He said it was a 520 chain but like I said it was way too long! Is 520 too big for 13T and 48T or have they sent him the wrong chain ?