what does this mean? Starting at standard gearing, if you go up 2 teeth on the
back then your acceleration should be 4.36067% faster, technically speaking...
So, if your 0-60 is 3.5 seconds then this change in gearing should take it to
3.3471655 seconds. Or thereabouts.
Or, if your top end is 170 mph in standard
gearing and you go up 1 tooth at the rear then it will drop to 166 mph. Go up
2 teeth, then it will drop to 162 mph.
Or, if you go to 16/48, your top
speed will drop to 151mph, acceleration will be 10.86474 % greater and the side
effects will be enormous! Acceleration will be 10% faster!
Here's the working.
2.706 - 2.647 = 0.059
0.059/ 2.706 x 100 = percentage gain/loss.
Here's the reality.
In racing circles, these ratios are really important.
The mechanic (and usually the rider) wants the rider to be topping out at the
fastest part of the track at full throttle, at the top of the power curve, in
top gear. So you change the size of the sprockets accordingly. It's faster than
On a practical note, it is always better to increase
the size of the rear sprocket as the circumference of the sprocket increases -
your chain will last longer. If you go smaller on the front, the circumference
decreases and this will wear out your chain.
As for changing chains and
sprockets together, well it's a bit of an old wives' tale. The story goes that
they wear into each other and if you change a sprocket then it will wear out your
chain. Not strictly true - I'm not going to do the maths for you but would you
like to know how often the same tooth goes into the same link of the chain? About
once every couple of hundred revolutions. This means that every link gets to fit
every tooth and every tooth gets shaped to fit every link so changing a sprocket
is hardly going to bother it. We're not talking blue printing here are we so it's
much more fun to buy a new rear sprocket with an extra tooth and stick it on.
What's it going to cost you and how much fun are you going to get back?
much further can it go? Will your bike pull power wheelies if you go up two teeth?
Don't know if you can calculate this as we are all fat, pie eating gits and it
depends on so many factors but you could put the bike in a more powerful part
of the rev range that allows you to ride easier. F'rinstance, if you are always
on the motorway in the mornings and you want to get past traffic and 80 mph equates
to 6000 revs, then going up two teeth will mean that you are sat at 6262 revs.
If this puts you closer to the faster part of the engine and then you are going
to accelerate 4.36067 % faster anyway then it could be useful.
you are on an 'Ace and I don't even drop a cog to overtake. I just use the twisty
thing on the right and it fucks off anyway!