FSA SL-K Crank Compact vs Standard

simonj

Hi, I currently have an SL-K 172.5 with 46/36 cross rings on a SuperX and want to change it to an SL-K 170 with 34/50 or 34/xx? Seen a cheap SL-K Standard, so does anyone know if the FSA SL-K Crank is the same spider (i.e. 110mm) for both Compact and Standard (rather than 110mm vs 130mm) hence the only difference is the rings? Could I buy the standard (cheap 170mm) and change the rings? Also is it possible to just change one ring to give 34/53 to it or would something not fit or be quite right, i.e. rear derailleur to short or chain line wrong - not quite sure what chain line means?! Sorry if a bit of a dumb question.

mitchgixer6

I'd imagine that the standard chainset will be 130mm and the compact will be 110mm. This is usually the standard. You could easily change the rings on either.

53/34 is usually a no no as the jump from the small ring to big is too much for the chain to handle easily when changing up.

I have a good compromise on my 110mm chainset, 52/38.

turnerjohn

mitchgixer6 wrote:

I have a good compromise on my 110mm chainset, 52/38.

you can get 52 / 38 rings for 130mm standard....its what I run ! 38 is the smallest you can fit on a standard 130mm though so be sure you dont want smaller before you buy ......or fit a bigger cassette

Monty Dog

Road front mechs can only handle a 16 tooth gap - and the bigger the difference the slower, less reliable the change - hence why people run 36/46 for CX. A 39/53 will use a 130mm spider and as said, the smallest chainring you can fit is 38 whereas you can fit a 34 on 110mm spider.

simonj

Cheers, I got confused as looking on the FSA website it says their standard is 110 :-
http://www.fullspeedahead.com/products/ ... d-Crankset