Gear ratios question?

AlanW
AlanW Posts: 291
edited April 2009 in MTB general
I come from a road riding background and as such am used to a close ratio 10 speed cassette.

Up until last Sunday I have only really played about on my MTB, but I rode the HONC last weekend and the thing that killed me the most was the wide ratio on the cassette. In my case 11-32 on a 9 speed, XT Deore cassette, .

I rode the whole event and did not have to use the very small inner front chain ring, which seems a waste to me.

On my Audax bike, I have a triple chain set, 28/39/52 with a 12/23, 10sp cassette. I find this ideal and will get me up anything even after 100miles or so of riding.

But I cannot find a MTB cassette that gives me anything anywhere this ratio, so could I fit a road cassette instead, say a Ultegra 9sp 12/25?

So assuming that it does fit, are there any problems that I am missing?? As it seems so simple to fix my problem.

Thanks in advance.....
"You only need two tools: WD40 and duct tape. If it doesn't move and it should, use WD40. If it moves and it shouldn't, use duct tape"

Comments

  • FSR_XC
    FSR_XC Posts: 2,258
    In my experience I do not notice the wide ratios when riding off road.

    I do notice on road, where I am used to the closer ratios of a road bike.

    As for the 'granny' ring - you will use it if you get some proper climbs in. I don't know anyone who didn't need 'granny' for a couple of the hills around Newham Park for the Soggy Bottom series.

    It may be that you are particularly fit.

    IIRC it is possible to fit a 9 speed road cassette on a MTB.
    Stumpjumper FSR 09/10 Pro Carbon, Genesis Vapour CX20 ('17)Carbon, Rose Xeon CW3000 '14, Raleigh R50

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  • nicklouse
    nicklouse Posts: 50,675
    BTBR
    no probs fitting a road cassette. But HONC was not really have any demanding hills i hear.

    Or lets put it differently having to get off and carry the bike 'cause the MTBers were spinning the granny rings was not faster.

    I would stick with it as it is for a while just dont use the granny ring, but you will love it when you need it.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
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  • GHill
    GHill Posts: 2,402
    Should be fine mechanically (some pro downhill riders use road cassettes).
  • AlanW
    AlanW Posts: 291
    Well I have just found a nearly new 9sp cassette in the garage, 14-25. Not an ideal ratio I admit, but it will do just to try it out.

    So that will give me a lowest gear of 22t granny ring, with a 25t at the rear. Surely that's plenty low enough to get up most things isn't it??

    Just had a quick whiz up the lane and it all changes ok. Bit lazy on the way up the cassette and could do with a little tweak if I decide to keep it on. But I'm reluctant to alter anything just yet, as when the MTB cassette was fitted it changed perfect and it would be just my luck to mess it all up! :oops:

    Need to take it up the local woods over Easter and attempt some hard climbs. :D
    "You only need two tools: WD40 and duct tape. If it doesn't move and it should, use WD40. If it moves and it shouldn't, use duct tape"
  • supersonic
    supersonic Posts: 82,708
    22/34 on some hills here is not enough!

    By using the 14-25 you will indeed close the ratios up but lose a significant amount of your highest gears.

    Reason why MTBs are like this is that the terrain and slopes is so much more varied than the road.
  • AlanW
    AlanW Posts: 291
    supersonic wrote:
    22/34 on some hills here is not enough!

    By using the 14-25 you will indeed close the ratios up but lose a significant amount of your highest gears.

    Reason why MTBs are like this is that the terrain and slopes is so much more varied than the road.

    But in my experiance, and by my own admission I am NOT a MTB rider I must add, but when you get down to gearing such as 22/34, you cannot keep the front wheel from lifting up in the air or you start wheel spinning. So either way, you aint gonna get up it.

    Furthermore, the speed you are now going you may as well walk and save your breath?

    I was watching some of the goons of the HONC attempting some of the long drags, NOT climbs. And they were in the lowest of gears, and spinning like a mad thing doing just a few mph?
    "You only need two tools: WD40 and duct tape. If it doesn't move and it should, use WD40. If it moves and it shouldn't, use duct tape"
  • supersonic
    supersonic Posts: 82,708
    Well, I can say that I can keep the front wheel down, and not slide!
    I also find that steady spinning up some climbs is more efficient than walking.

    I suppose it comes down to what works best for you.