Gear ratio’s?

[BikeMax]

I have the Shimano compact with an 11-23 for racing and a 12-25 for training - it has been a very positive change and I have had no problems with the chain dropping or poor changing. I have heard that the Shimano is a better bet re changing than the FSA.

All in all a really good option.

[Guest Michelle]

ewep: Cycle tech stocks FSA.  BTW did you ever pick up your bike mount from them??  They haven't called me yet to say they have more in smileys/smiley19.gif

smallrebel: I don't suppose you have the table for 30, 39, 52 with a 11-23 cassette? 

[JimFrase]

I was looking into compact crank sets and I found this interesting

uploads/JimFrase/images/2006-08-04_142153_Compact_Crank.JPG

[eddy]

 

One question for the Technical minded / informed, or in Linnega's case both.

If a compact cranckset offers the benefits which seem quite compelling, why have we been saddled with 53/39 for as long as I can remember ?

Is there any benefit to 53/39 other than the smaller drop between the front rings ?

Is it more difficult to find "the next" ratio up or down on a compact ?   I know that there is a lot of overlap on a 53/39 crank paired with 11/21 or 23. Is there less of an overlap on the compact crankset and if so do you have more changing to do or it ?

[Grapkas]

I allways look at what the pro's overseas are doing and none of them are riding with compact crank sets so my 52/39 and 12/25 is fine, i'm gonna stay of the bandwagon for now!

[_Daemon_]

 

I allways look at what the pro's overseas are doing and none of them are riding with compact crank sets so my 52/39 and 12/25 is fine' date=' i'm gonna stay of the bandwagon for now! [/quote']

 

Dunno at what pro's you are looking, but for the last how many years, alot of the guys, Lance included as far as I know used compact cranks in the mountain stages of the TDF.

 

[Grapkas]

Hulle ry beslis nie met die grannie gears wat my pelle op hulle bikes sit nie!!!

[Grapkas]

OK EK GAAN NET HIER STOP VOOR EK IEMAND KWAAD MAAK! CHEERS ALMAL EN LEKKER NAWEEK!!!

[BikeMax]

I allways look at what the pro's overseas are doing and none of them are riding with compact crank sets so my 52/39 and 12/25 is fine' date=' i'm gonna stay of the bandwagon for now! [/quote']

I am not sure that this is a relevant comparison Grapkas. In the case of male pro overseas riders they generally have a threshold power of upwards of 400w, in comparison to even top local riders who are closer to 350/360w and the middle pack vet racers such as myself at  nearer to 290w. On this basis I would not expect to be using the same gear ratio's as the pro's nor think it the best model to follow.

[Grapkas]

Another argument is that we don't have mountains that come close to the ones they have so i really don't think it is worth it to put a compact crank set on for the hills that we have!! I have a 25 and that is fine!! I have seen people drop like rocks in our races cause they go to their small blades and they have the compact and then they have to spin themselves silly to keep up!!!  

[BikeMax]

Another argument is that we don't have mountains that come close to the ones they have so i really don't think it is worth it to put a compact crank set on for the hills that we have!! I have a 25 and that is fine!! I have seen people drop like rocks in our races cause they go to their small blades and they have the compact and then they have to spin themselves silly to keep up!!!  

Not sure about that either. On most of the steeper climbs in CT such as Red Hill or Kloof Nek etc , if I ride in a 39/25 then to pedal at a cadence of only 80rpm requires well over 300w which is beyond most fun riders capacity (and many racers) On my local climb of Kloof Nek where I do my hill 20 minute intervals, if I ride my 39/25 then I average a cadence of ~55/60 at my threshold power of 290 whereas if I ride my 34/25 then I can average ~75-80rpm which is far smoother and more rythmic and also easier on the legs.

You do not need excessively long or steep climbs to benefit from a smaller gear ratio and neither does it mean you have spin frantically (that is just poor gear selection)

[Gumpole]

 

One question for the Technical minded / informed' date=' or in Linnega's case both.

If a compact cranckset offers the benefits which seem quite compelling, why have we been saddled with 53/39 for as long as I can remember ?

Is there any benefit to 53/39 other than the smaller drop between the front rings ?

Is it more difficult to find "the next" ratio up or down on a compact ?   I know that there is a lot of overlap on a 53/39 crank paired with 11/21 or 23. Is there less of an overlap on the compact crankset and if so do you have more changing to do or it ?

[/quote']

about 6 to 10 years ago all bikes came with 52/42 and not 53/39, this meant that hopping between the big blade and the small blade was very easy....

then things changed and the pros started using 53/39 (I'm sure people complained about it initially) but pretty soon everybody only used 53/39 which was a bit more of a pain to switch between the big and small ring, but gave more gearing options for fast flats and steep hills....

now the pros start to use compact cranksets (albeit only for mountainous terrain), moer and more crank manufactureres have started to produce compact cranks, even shimano started last year. In a couple of years they will become very common.

the future? maybe a granny gear for all smileys/smiley36.gif, forget it Scotty.

Finally because the diameters of all the cogs cranks are smaller in compact than normal cranks BUT the distance from crank to rear wheel is the same, the angle of the chain is less steep in a compact setup, therefore there is more scope to 'cross over' gears. ie when you are in the 50/17 and things start to get hilly you can easily go to the 50/19 or 50/21 (I find anyway)

[SwissVan]

Compacts have a weight advantage (not really sure how significant an advantage though) and obviously better options for climbing, they are limited slightly with regards to top end speeds like on long downhills and really fast bunch racing and sometimes the ratios feel to close i.e. you need to change up or down 2 gears instead of one to noticeably feel a difference.

2007 and onwards will see 10 spd Cassettes with a wider range ratio (11-26 and 11-25) becoming more readily available which will offer more climbing options with the same top end of the 11 for the 53/39 Brigade.

If you are an average rider in a hilly area a compact would be the better option imo

[linnega]

Grapkas - Many of the pros are using compacts especially on mountain stages.  And Bikemax is right about the power output.  If the climbs are short (under 5k) then it is reasonable to use gearing that prevents you from riding at an optimal cadence, as the damage is less severe than it would be on a 25km mountain pass.  But there is no compelling reason to subject yourself to unnecessary suffering.

 

Gumpole is right about the straighter chainlines.  It is easy to ride 50-21 (on a 11-23 cassette) without any chain rub.  I often use the 50-23 when I have the 12-25 cassette on the back.  Having the extra gear for climbing also allows you to ride a number of different gears to keep your cadence constant.

 

The reason people haven't been riding compact is mostly because Shimano haven't been making them.  It is only in the last 15 years or so that the pro's have started to be more active in selecting their equipment and more eager to try new technologies.  That has seen more innovative component companies always looking for new fads.  They are not all effective, but compacts I feel are a very positive fad.

 

[ewep]

 

ewep: Cycle tech stocks FSA.  BTW did you ever pick up your bike mount from them??  They haven't called me yet to say they have more in

smallrebel: I don't suppose you have the table for 30, 39, 52 with a 11-23 cassette? 

[/quote']

 

Michelle, did and I'm using it already (has Jason put his on his bike yet?, if not, steal his!)  It looks ***, but works GREAT!!!

 

[Guest Michelle]

Ewep: Jason has put it on his bike already.. the only complaint he has is that it captures laps when the road surface is bumpy!! smileys/smiley5.gif