crankset ???

mrfizzed said:

greetings folks, i am new here and new (or new again after a 15 yr hiatus) to cycling. anyway i have a random question. i bought a bike (used) and it turns out the rt crank is stripped. i have a triple crankset (52/42/30) and found a crankset by same manurfacturer but it is a double ring (53/39). can i simply swap the double crankset for the triple. both are 172.5mm thanks in advance and i look forward to spending lots of time on here.

Maybe, yes ... maybe, no.

What brand crankset is it?

What type of BB interface does each crank use?

Tentatively, if you can-and-do make the swap, remember to adjust the inner stop on the front derailleur so that you don't shift the chain on to a soon-to-be-non-existent granny ring!

mrfizzed said:

greetings folks, i am new here and new (or new again after a 15 yr hiatus) to cycling. anyway i have a random question. i bought a bike (used) and it turns out the rt crank is stripped. i have a triple crankset (52/42/30) and found a crankset by same manurfacturer but it is a double ring (53/39). can i simply swap the double crankset for the triple. both are 172.5mm thanks in advance and i look forward to spending lots of time on here.

just try and You will see :-)

I have switched to double crankset wih 50/36 or 50/34 gearing.. less weigh on thebike, with a 11-28, 10 spd cassette, it offers similar gear range than a tipical triple crankset with a 30T small ring, I can't really spin at 160 rpm with a 53T large ring anyway.

The weight difference makes no significant impact on performance. Anyway, compact cranks are not always lighter than the standard versions. In fact, they can be heavier.

mrfizzed said:

greetings folks, i am new here and new (or new again after a 15 yr hiatus) to cycling. anyway i have a random question. i bought a bike (used) and it turns out the rt crank is stripped. i have a triple crankset (52/42/30) and found a crankset by same manurfacturer but it is a double ring (53/39). can i simply swap the double crankset for the triple. both are 172.5mm thanks in advance and i look forward to spending lots of time on here.

you'll need to chang the spindle or bottom bracet cartridge for that switch

alienator said:

The weight difference makes no significant impact on performance. Anyway, compact cranks are not always lighter than the standard versions. In fact, they can be heavier.

My compact crankset are definately lighter in weight than my old double 53/39 crankset. even lighter than a comparable triple crankset, short cage rear derailleur vs long cage triple derailleur, less chain length, smaller front derailler.. compat drive double chainring setup all add up to weight less than comparable triple drivetrain.

Sure compact cranks can be heavier than standard version, but heavier than what? be more specific about your facts. It's okay to avoid posting if you don't know the specifics.

A said:

My compact crankset are definately lighter in weight than my old double 53/39 crankset. even lighter than a comparable triple crankset, short cage rear derailleur vs long cage triple derailleur, less chain length, smaller front derailler.. compat drive double chainring setup all add up to weight less than comparable triple drivetrain.

Sure compact cranks can be heavier than standard version, but heavier than what? be more specific about your facts. It's okay to avoid posting if you don't know the specifics.

I see. Well thank you for your gracious offer allowing me not to respond. Specifically, since you asked, my THM compact Clavicula's weighed more than the standard version. Further I did not state all makes have this relationship.

As for weight, so what? It doesn't have any substantial performance benefit. In general, the bike rider system rolling down, up, or along the road mass much greater than weight differences in the drive train, or for that matter, anywhere. The difference of moments of inertia between the three different crank types is insignificant. The moment of inertia of any crank in general is insignificant.

In fact buying a compact crank just because it's lighter would be just stupid, unless you're dedicated weight weenie, who's raison d'etre is to have the lightest bike possible.

Do the math.

alienator said:

I see. Well thank you for your gracious offer allowing me not to respond. Specifically, since you asked, my THM compact Clavicula's weighed more than the standard version. Further I did not state all makes have this relationship.

Really? what's the weight difference, have you weigh them yourself? where are the specific weights of each crankset?

alienator said:

As for weight, so what? It doesn't have any substantial performance benefit. In general, the bike rider system rolling down, up, or along the road mass much greater than weight differences in the drive train, or for that matter, anywhere. The difference of moments of inertia between the three different crank types is insignificant. The moment of inertia of any crank in general is insignificant.

In fact buying a compact crank just because it's lighter would be just stupid, unless you're dedicated weight weenie, who's raison d'etre is to have the lightest bike possible.

Do the math.

Stupid? maybe in AZ there is not need for a lighter road bike. Weight is not important? why not just use tried and true Shimano crankset rather than your THM compact Clavicula's?

What math?

Maybe weight is not a priority to you when you purchase a road bike.
Weight weenie.. maybe, but majority of cycling who purchase road bikes would go for a lighter bike than a heavier one when priced at level.. weight weenie most are not..

A said:

My compact crankset are definately lighter in weight than my old double 53/39 crankset. even lighter than a comparable triple crankset, short cage rear derailleur vs long cage triple derailleur, less chain length, smaller front derailler.. compat drive double chainring setup all add up to weight less than comparable triple drivetrain.

Sure compact cranks can be heavier than standard version, but heavier than what? be more specific about your facts. It's okay to avoid posting if you don't know the specifics.

I think his point(and he can speak for himself) is that the teeny weight savings(if indeed there is any) on going to a compact will have no significant impact on your cycling performance.

Peter@vecchios said:

I think his point(and he can speak for himself) is that the teeny weight savings(if indeed there is any) on going to a compact will have no significant impact on your cycling performance.

My previous post was comparing the weight saving from a triple drivetrain to a compact double drivetrain, combine weight of different crankset, front and rear derailleurs, bottom bracket and chain between a triple drivetrain and compact double drivetrain has got to be in the neighborhood of 200+grams to be conservative.

If indeed Alienator is spending upwards of $700-800 (or more) for his THM compact Clavicula crankset, yet he calls me stupid and a"dedicated weight weenie".. at that price, you can likely get a decent road bike for them crankset.