MTB cranks

dannydc

Hi

I've got a Trek 5200 with slicks that I use for commuting and have just changed the rear cassette and chain. Now I need to change the cranks as it's slipping (I know you should change them together - I was hoping the chainrings weren't worn but obviously are). The chainrings are riveted on (cheap Suntour), but the bottom bracket seems fine.

Can anyone recommend decent and cheap triple (8-speed) square taper cranks? It's currently got a 42-?-24, but I never use lowest gears and regularly run out of steam at the top end so a 48t (or bigger?) would be better.

Thanks,
Danny

njee20

5200 was always a road bike, notably the cheapest OCLV carbon one, you sure that's what it is?

Don't mess around with square taper, just get a Deore trekking chainset - if you change chainset you'll likely need a new BB anyway, that avoids the middle step!

dannydc

Good spot - it's a 4300! And the cranks say SR Suntour.

I'll have a look at the Deore trekking tomorrow - thanks!

njee20

This is what you want, available with 26/36/48 rings.

Ouija

njee20 wrote:

This is what you want, available with 26/36/48 rings.

+1

It's what i use and much lighter than the Suntour stuff. It's a 8/9 speed crankset but works better with a 9 speed chain (even if your using 8 speed cassettes and shifters) as the slightly wider 8 speed chain can rub against the shift ramps when in the middle ring and smallest rear sprocket.

Also future proofs you as it will allow you to go 9 speed at a later date, if you want to (i did, eventually). And replaceable rings so you won't have to keep buying new cranks when the old rings wear out.

The Rookie

If you go to trekking ratios you should need to fit a longer chain.......unless the current one is too long.

Running out of puff on a 42:11 ratio is somewhere over 30mph, are you sure you really are and that it's not you thinking it?

dannydc

I can get to around 30 but I'd rather do it a bit more relaxed. My commute in is a long steady slight downhill so I end up rolling parts of our when is rather be pushing on.

I've got some spare chain links so I can extend it a bit for the bigger chainring.

D

Chunkers1980

Not the best idea to mix chain ages. A whole new 114 link can be had for about £8 anyway.

dannydc

The chain is new- I've used it twice with the new cassette so it's just the chainrings that are old. Having said that, to remove a few links from the new chain I bought a cheap chain tool which I wouldn't normally do, and obviously it broke on first use so I'll have to get a decent one to add the links back.

dannydc

Just wanted to say that I made the plunge and got the Deore M590 cranks with the 48 ring and got the frame faced, plus a 9-speed SRAM chain and the difference is amazing. The changes are quick and accurate (little bit more tuning needed at the back or a new mech maybe!) and the top gear is loads better on the ride in.

Thanks for the help!

Danny