What to replace my crankset with, whole thing or partial??

russboy

First of please excuse the terminology!

Recently been lucky enough to have my frame replaced under warranty & at the same time had the cassette, chain & front mech replaced.

However on the largeest chain ring there was mention the teeth are quite worn. Its just that one really, the other two seem pretty good.

So do I replace the one chain ring or the whole crankset?

What I have at the mo isnt the most expensive so looking to replace like for like. Currently I have Truvativ crank arm, with the largest chainring marked up as "Trushift AL-7975-T6"

Cant get pics up at the mo as am at work

Any thoughts most welcome

Chunkers1980

If that crank has removable rings then yes, just change the ring - like for like is the best route to save hassle.

When someone said it's worn, was that because you were experiencing problems, or just a passing comment. If it ain't broke don't fix it.

russboy

Just had a search from a post on here when I bought the bike:

TruVativ Five D 3.1, 44/32/22 with Alloy Outer Chainring

russboy

Chunkers1980 wrote:

If that crank has removable rings then yes, just change the ring - like for like is the best route to save hassle.

When someone said it's worn, was that because you were experiencing problems, or just a passing comment. If it ain't broke don't fix it.

Was jumping quite a bit, hence the new cassette & chain, but done nearly 2k on them so no surprise. From looking at it now it looks pretty worn down, shame im at work cant get the pic up! Just thought as id replaced the rest I should poss do this as well.

Can remove the outer ring no probs

cavegiant

Also check the prices, sometimes you can find a deore or LX crankset cheaper than new rings.

This way you not only get rings, but a apre BB and cranks if you need.

russboy

cavegiant wrote:

Also check the prices, sometimes you can find a deore or LX crankset cheaper than new rings.

This way you not only get rings, but a apre BB and cranks if you need.

Cool looking now. Presume any MTB Chainset will fit?

Do I have to stick with 44/32/22 rings? What are the consequences if I go larger, if they exist? Obvioulsy the chain may be an issue just wondering if it would increase top end speed at all

russboy

http://www.wiggle.co.uk/fsa-moto-megaex ... t-2007-oe/

Looks cheap, subject to compatibility, suspect its not though!

FunBus

You can go larger - 48T is usually the largest most MTB'ers go. Only issue this may cause is with your front mech and chain (but as you have a new chain, you can just keep an extra link or two on to take away the tension).

russboy

FunBus wrote:

You can go larger - 48T is usually the largest most MTB'ers go. Only issue this may cause is with your front mech and chain (but as you have a new chain, you can just keep an extra link or two on to take away the tension).

Thanks

Would this allow for higher top end speed?

Do you have any idea what would be compatible with mine? Sorry pretty cr@p at this kind of thing. Got no probs fitting it just dont know what would actuallyfit!

FunBus

Yeah, a bigger chainring, or a smaller cassette will mean you can go faster (legs permitting).

As for being compatible with yours, do you mean the front mech or are you going back to your original question? If its your front mech, yes, you should find your mech will be compatable with chainrings of 44-48T, but its worth double checking otherwise you'll spend hours trying to set it up - it should say on the mech or inside the bracket.

If its the chainset you're asking about. A lot of MTB chainsets now come with bottom brackets (unlike the FSA one in your link) its worth spending an extra fiver on one complete with BB as this will remove any question over compatability - also you'll have a brand new BB....

russboy

FunBus wrote:

Yeah, a bigger chainring, or a smaller cassette will mean you can go faster (legs permitting).

As for being compatible with yours, do you mean the front mech or are you going back to your original question? If its your front mech, yes, you should find your mech will be compatable with chainrings of 44-48T, but its worth double checking otherwise you'll spend hours trying to set it up - it should say on the mech or inside the bracket.

If its the chainset you're asking about. A lot of MTB chainsets now come with bottom brackets (unlike the FSA one in your link) its worth spending an extra fiver on one complete with BB as this will remove any question over compatability - also you'll have a brand new BB....

Well the front mech is brand new so nice & clean & i'll have a look later

Yes I was asking about the chainset. I was (naively) under the impression I could just take the old chainset off & put a new one on, guess not!

Why is the BB named so? Seems a strange thing to call it really, am I correct in thinking its basically what housing the bearing etc & what the arm on either side mounts to? Therefore would any MTB BB fit or are they different sizes (distinct lack of knowledge here!!)

FunBus

There's a host of BB's out there - HTII (HollowTech 2) is the most common for MTB these days. These are outboard bearings so simply consist of two bearing houses which sit either side of the frame (idea behind it - as its outside the frame there's more room for bigger bearings, bigger bearings = longer lasting. Although, this really doesnt seem to be the case with most of them!).

i'd imagine that's what you've got as the other option is a cartridge bottom bracket - this slots into the frame and houses the bearings inside the frames tubing. There are loads of variants of axle length and shape so obviosly you need to keep like for like.

Both BB's mentioned above will fit in your frame, but obviously you need the right chainset. Hope that doesnt confuse things even more.

Best bet is go to your LBD to have a chat with them...........(Local Bike Shop in case you were wondering)

russboy

FunBus wrote:

There's a host of BB's out there - HTII (HollowTech 2) is the most common for MTB these days. These are outboard bearings so simply consist of two bearing houses which sit either side of the frame (idea behind it - as its outside the frame there's more room for bigger bearings, bigger bearings = longer lasting. Although, this really doesnt seem to be the case with most of them!).

i'd imagine that's what you've got as the other option is a cartridge bottom bracket - this slots into the frame and houses the bearings inside the frames tubing. There are loads of variants of axle length and shape so obviosly you need to keep like for like.

Both BB's mentioned above will fit in your frame, but obviously you need the right chainset. Hope that doesnt confuse things even more.

Best bet is go to your LBD to have a chat with them...........(Local Bike Shop in case you were wondering)

Thanks, will prob have to end up doing that, but then I end up paying their prices rather than internet prices, hence trying to do a bit of research myself really