Rear derailluer and cranksets?
 

Howdy,

Doing a tour with a buddy in hawaii in a few weeks and guess what happens? Rear derailluer catches on the wheel and cracks! I just noticed my cranksets are in lousy shape and those need to be replaced.

What brand/parts exactly would you guys suggest? I'm totally lost on the subject.

Budget of $400 and doing touring on a Trek 520 (one with the busted derailluer). Same friend will install the parts but I need to know what to buy! I keep hearing "mountain bike gearing for touring" but have no idea what that means.

I need parts though - ordering by next week.

Thanks a bunch,

Marska

shimano all the way...if you cant swing 105s, which is what your 520 should have origionally anyways, go with Tiagra...they'll do just fine. MTB gearing...all you need to do is for your crankset, get 3 rings vice 2...gives you much lower gearing for those loaded climbs up Mt. Kilawea, or whatever other big inclines you have ahead of you. What did you have origionally? Have fun!

shimano all the way...if you cant swing 105s, which is what your 520 should have origionally anyways, go with Tiagra...they'll do just fine. MTB gearing...all you need to do is for your crankset, get 3 rings vice 2...gives you much lower gearing for those loaded climbs up Mt. Kilawea, or whatever other big inclines you have ahead of you. What did you have origionally? Have fun!

How old is the bike?

What rear derailleur you use depends on the size of the cassette. My 520 had a 11-32 or 11-34 cassette, I don't remember which. Road rear deraillers typically only handle up to a ~28 large cog on the rear cassette, MTB rear derailleurs can handle up to 34 or more, my 520 had a Shimano LX derailleur on the rear. Shimano LX or XT will be planty durable and not too spendy.

If you need a new crank set I see Nashbar has the Shimano LX trekking crankset on sale for, I think $69 not including the BB. Gearing is 26/36/46, half way between the std 22/32/44 MTB and 30/42/52 road cranks.

Old Fart - Bike was bought used from 1992. Nashbar?

So Cal Commuter - I'm arguing with him over the phone about what were going to hit. Theres that old, haunted, highway, the usual sites, plus some senic ventures he is familiar with (sugar cane fields ahoy!).

Shimano Duero LX by the way (guess its stock).

Ah... So I can get away rather cheaply indeed. Ten speed would be overkill I guess? ($700 shifting, right? heh)

Looking at those options the MTB cranks I compared were lighter than the road cranks, and looked plenty stout. Why is it people seem to prefer road tripples for the average touring application? Assume at the outset that I am probably going to change 2 out of three rings in either case, so that isn't a big deal for me.

LX/XT on the rear
The crank depends. What kind of gearing do you want. A road triple's gonna be able to run bigger gears, which is not really an advantage in most touring situations. A mountain triple can run a very small granny, which can be helpful. The disadvantage is that some road front derailluers may not be able toi handle the smallest grannies.
I'd just go with an LX/XT crank. Note that you'll probably need a new BB if your crank's from 92.

Since were on the subject
Im looking at an off-brand bike in an attempt to save a couple bucks. It comes equipped with a Shimano Alivio for the rear derailer, and a Shimano TX-71 crankset.

Im told that offbrands will have crappy parts, but Ive found the same parts listed on various Trek bikes as well. I can already figure these guys arent top of the line, but are the reasonable?

PS: Sorry to hijack, but I didnt want to start a new thread with essentiall the same question.

Most 520's I seen had LX cranks with 44-32-22 rings. If you have a square taper BB one step down to Deore cranks will be just about as good and cheaper. I started out with Deore and LX derailleurs and when they wore out upgraded to XT. The XT is more solid, much smoother shifting and appears to be wearing better. 11-34 is the best cassette and not just for the "34" but the spacing on the last couple of cogs is better for serious loaded climbing.

I just replaced the 105 crankset that was on my 520 with a Sugino XD-600 46-36-26. I've seen these advertised on e-Bay with several different chainring combo's, all for about the same price (about $80). Best yet, they utilize a square tapered bottom bracket which is what your '92 Trek probably has on it, unless you've upgraded more recently. Happy Riding!
CC

I'd go with a new Sugino crankset (46-36-26), new bottom bracket, a new Deore or Deore LX rear deraileur-- with new cable and housing all the way around. Less than $200 in parts. Check your chain, cassette, brakes-- it's a good bet you made need to replace some other parts as well.

Remember that the mechcanical systems that bike use break down at the weakest point. I've seen cyclists upgrade to really fancy cranks, deraileurs, ect... and have the bike break down with bottom bracket trouble, headset trouble, cable/housing trouble--- the non-sexy stuff that many cyclists forget to replace.

Which Shimano Deore XT rear derailluer? (I see about seven or eight different types under that brand).