On Mon, 09 Jun 2003 13:51:31 +0000, David wrote:
>
> "Dave Moak" <
[email protected]> wrote in message
>
news:[email protected]...
>> I have a mountain bike that I ride primarily on the road. The gearing that came with the bike is
>> too low for road riding.
>
>> What's the easiest way to increase the gearing? Is it possible to swap chainrings?
>
> On most cranks, yes. On really cheap ones, no. It should be obvious by inspection. If there is a
> circle of 4 or 5 bolts hoding the big ring on, it should be easy to replace. Check the # of teeth
> (marked on the ring, or count them). If it's 42 or 44 (and you have an 11t cog in back), probably
> going to 48 will solve your problems.
The problem is going to be availability and cost. The 4-bolt Shimano chainrings (104mm) will be hard
to find in more than 44 teeth. 5-bolt 94mm rings are pretty easily found in sizes up to 46; 48 takes
a bit more looking. There are some really large rings for downhills, but they are probably more than
you need. 110mm 5-bolt patterns apparently have a wider range of available sizes, but you may have
to look longer.
> You will need to move/adjust the front derr. You will likely need to add a couple of links to
> your chain.
Don't do that. The pin you remove to add links will, with modern chains, cause a weak link. Better
to just replace the chain.
>>Or do I need a whole new crank/bottom bracket?
>
> It may be better to buy a new crank/rings. Unless the new crank wants a different spindle length
> (or type), no need to change the BB.
Well, it does depend on what you have now, which can vary from standard sizes with easily-replaced
rings to non-replacable rings on cheap cranks.
Of course, the real solution to improving your riding on the road is, surprisingly enough, to get a
road bike.
--
David L. Johnson
__o | Accept risk. Accept responsibility. Put a lawyer out of _`\(,_ | business. (_)/ (_) |