How to Increase maximum speed

[betski]

Seems like 44/32/22 chainrings are standard on modern mountain bikes which equates to about a top speed of 25-30mph. I want to be able go go faster on the road sections of my routes. Is it just a case of changing the outer ring to 46 teeth on my Shimano Deore or is there another way to increase maximum speed?

[hobbo31]

You could put a bit bigger chainring on just don’t go to big

[Steve Kish]

11 sprocket cassette would give a 108-inch gear top. Chris Boardman hold the current 25-mile time trial record on a 108-inch gear at 45 mins 57 secs, average of over 32.6mph.

If you want to average between 25-30mph on the road on an MTB, please can I have your autograph? 8)

[Gunner]

You could also look at the rear cassette and see if you could replace the smallest cogs you are using with anything smaller, that would have a similiar effect, or look at a combination of the 2, slightly increasing the front chainring size whilst slightly reducing the rear cassettes smallest sprocket.

Perhaps a browse through Sheldon Brownes site may give you a better insight into your gearing options.

😉

[betski]

ta for the replies. i’ve also pinged an email to the tech support of shimano. will post back with the reply 😀

[tomlevell]

Get a 29er and run 44:11 as the bigger wheels will make all the gears bigger.

Or get bigger draggier tyres to slow you down ;0)

[betski]

Shimano tech support responded within a day-

They suggest changing to a 48/36/26 chainring combination to increase top speed based on my setup of Shimano LX front derailuer and Shimano Deore rear.

Thought i could just change the outer ring but its probably not recommended.

[tomlevell]

You can and it will probably work but you may have front and rear mech issues and you’ll need a new chain.

[Steve Kish]

Good ol’ Shimano tech – never recommend one ring when you have the chance to sell three! 8)