MTB Double to Triple? or change Casette
Hello out there.
Currently riding a Rocky Mountain Grind, you can see the specs here.;
The bike has a 8-speed, 11 - 32 teeth in the rear, and a TruVativ Hussefelt w/ bashguard, 22/32 teeth in the front.
I find that I can't go fast enough, very quickly I'm winding out. Essentialy my question is, how do i get the bike set up to go faster?
I contemplated switching my front crank to a triple to get a larger outside gear, but after some research I learned I may be able to swap out the casette only.
A few questions, what is a compact double, and can I get it on a mountain bike? or only road bike?
How do i know if i already have a compact double
If i don't have one Is the compact double my best bet to getting higher speeds?
If i use a compact double, will i have to replace dereaileur and front shifter?
Is it a lot of work to go from a double to a compact double
Alternatively, can I just buy a differnet cassette ? something like a 22 36? or will i have problems if i go too large?
If i don't need a compact double what kind of casette should i buy to get a better top end ?
Thanks for your help.
Last edited by lukedecoste; 05-29-08 at 03:24 PM.
You have several options:
1. remove bashguard, install 42 or 44 tooth chainring in its place (may require new, longer chain) This will also involve adjusting your front shifting.
2. Remove 32 tooth ring and install a 36 tooth. (I think this may be what you meant when you asked about a 22 36 cassette? Actually "cassette" refers specifically your rear set of cogs.)
3. learn to spin faster.
4. No, you do not want a compact double. It possibly won't fit (chainring/chainstay interference). If it did fit, you must decide if your 32T front and 32T rear combo is the lowest hill-climbing gear you need on this bike. Trust me, put this out of your mind and do 1, 2 or 3.
The 11 tooth cog on your cassette is the tallest (highest) gear you can get, so changing it won't help at the absolute high end of your gearing (unless you want more options in higher gear ratios).
If you determine the BCD of your crank arms, you may be able to simply swap in some larger chainrings. Here's a brief primer on gear ratios. Follow the links for more information.
You shouldn't have trouble swapping in a new double, assuming you can't get larger chainrings for your existing crank arms. But if you go bigger than a 46T on the big ring, your front derailleur might not work very well. In that case, if you went for a compact road double, for instance, you'd need a FD compatible with it. Problem is, I don't think top pull road FD's are commonly available (which is what you'd need).
Then you'd have to find a crankset that's compatible with ISIS DH bottom bracket, or you'd need to replace the bottom bracket as well.
You'd also need a new chain, or to lengthen your existing chain.
Oh yeah, good point.
Originally Posted by jimmythefly