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 11-24-00, 02:29 AM #1 claude Senior Member Thread Starter     Join Date: Oct 2000 Location: Malta, Europe Bikes: Posts: 59 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 0 Post(s) Hi to all, sorry if this question might seem banal to you people, but I just realised (about time I did ??) that newer bikes have got much smaller chainrings than my 10 year old MTB... want to make sure before I buy some bits... Is the gear ratio measured as the difference between the number of teeth between the chain ring and cog ? Would a, for example 44-11 gear ratio feel exactly the same as a 48-15 ?? thanks for any feedback claude
 11-25-00, 03:08 AM #2 madsnake Member     Join Date: Nov 2000 Location: Christchurch. New Zealand Bikes: Posts: 33 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 0 Post(s) Chainrings The formula is: number of teeth on chainring/number of teeth on cog x wheel diameter = gear inches. The result is the distance travelled for one pedal revolution. Hence 44:11 = 104 gear inches. 48:15 = 83 gear inches. 52:13 would give you 104. A good cycle mechanics book should give give you a table of gear inch equivalents.
 11-27-00, 01:34 AM #3 claude Senior Member Thread Starter     Join Date: Oct 2000 Location: Malta, Europe Bikes: Posts: 59 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 0 Post(s) so, if I understood correctly, my older bike with a 48:13 ratio would actually be slower than a newer bike with 44:11 ratio, although the difference in teeth is actually more in the older bike.... claude