11 tooth engine gear

[FurryOnTheInside]

If your speed at (X)rpm is NOT your top speed then increasing tooth count on the drive sprocket by 10% (11t is 110% of 10t !) and leaving the rear sprocket as it was, will increase your speed at THAT rpm by 10% Which is the same effect on gear ratio as if you decreased the size of the rear sprocket instead by a comparable amount, like 44t changed to a 40t.
11:44 = 10:40 = 1:4
11:40 = 10:not integer = 1.3.636363

The main advantages of less compact gearing (like 11:44) is
1. the reduced strain on the chain and teeth, allowing a monster of an engine to be used more safely (on the same type of chain) or
a lighter chain to be used on the same type of engine) for less power wasted in the drivetrain, and

2. the ability to fine tune ratios, to use ratios that are mathematically not possible or are just impossible to buy the right rear sprocket for with a 10t,
such as SR's 11:34 gearing, which is similar but not the same as 10:31, (and a 31t is probably difficult or impossible to find!).

 

[gary55]

I am so hill billy on this. I look at the 10 tooth sprocket and figure adding 1 tooth is about 10% increase. So if I,m getting 28.3 mph with the 10 tooth I'll ad 10% to that for the 11 tooth. 2.8 + 28.3 = 31.1. That's the redneck #.

 

[crassius]

yes, rotational speed of chain changes, but the actual speed of bike stays constant under all usual conditions

 

[crassius]

I am so hill billy on this. I look at the 10 tooth sprocket and figure adding 1 tooth is about 10% increase. So if I,m getting 28.3 mph with the 10 tooth I'll ad 10% to that for the 11 tooth. 2.8 + 28.3 = 31.1. That's the redneck #.

yes, if motor has the power to keep that same number of RPMs

 

[FurryOnTheInside]

I am so hill billy on this. I look at the 10 tooth sprocket and figure adding 1 tooth is about 10% increase. So if I,m getting 28.3 mph with the 10 tooth I'll ad 10% to that for the 11 tooth. 2.8 + 28.3 = 31.1. That's the redneck #.

I totally agree 110% , unless it's your top speed of course.

 

[gary55]

If your speed at (X)rpm is NOT your top speed then increasing tooth count on the drive sprocket by 10% (11t is 110% of 10t !) and leaving the rear sprocket as it was, will increase your speed at THAT rpm by 10% Which is the same effect on gear ratio as if you decreased the size of the rear sprocket instead by a comparable amount, like 44t changed to a 40t.
11:44 = 10:40 = 1:4
11:40 = 10:not integer = 1.3.636363

The main advantages of less compact gearing (like 11:44) is
1. the reduced strain on the chain and teeth, allowing a monster of an engine to be used more safely (on the same type of chain) or
a lighter chain to be used on the same type of engine) for less power wasted in the drivetrain, and

2. the ability to fine tune ratios, to use ratios that are mathematically not possible or are just impossible to buy the right rear sprocket for with a 10t,
such as SR's 11:34 gearing, which is similar but not the same as 10:31, (and a 31t is probably difficult or impossible to find!).

CVT.

 

[Deleted member 27811]

If your speed at (X)rpm is NOT your top speed then increasing tooth count on the drive sprocket by 10% (11t is 110% of 10t !) and leaving the rear sprocket as it was, will increase your speed at THAT rpm by 10% Which is the same effect on gear ratio as if you decreased the size of the rear sprocket instead by a comparable amount, like 44t changed to a 40t.
11:44 = 10:40 = 1:4
11:40 = 10:not integer = 1.3.636363

The main advantages of less compact gearing (like 11:44) is
1. the reduced strain on the chain and teeth, allowing a monster of an engine to be used more safely (on the same type of chain) or
a lighter chain to be used on the same type of engine) for less power wasted in the drivetrain, and

2. the ability to fine tune ratios, to use ratios that are mathematically not possible or are just impossible to buy the right rear sprocket for with a 10t,
such as SR's 11:34 gearing, which is similar but not the same as 10:31, (and a 31t is probably difficult or impossible to find!).

Check please...... my head hurts...

 

[ronALD]

I am so hill billy on this. I look at the 10 tooth sprocket and figure adding 1 tooth is about 10% increase. So if I,m getting 28.3 mph with the 10 tooth I'll ad 10% to that for the 11 tooth. 2.8 + 28.3 = 31.1. That's the redneck #.

Using dimensionless numbers is even faster and easier!
For your example, you change only the front gear, so the ratio for the rear gear is just 1, and the front gear change ratio is (10/11)
New Speed = Old Speed * ronALD = 28.3 mph * ( 1 / (10 / 11 ) ) = 28.3 mph * (11 / 10 ) = 31.1 mph

 

[FurryOnTheInside]

I'm pretty confused now
So with the 40tooth rear wheel sprocket and an 11 tooth engine sprocket, will that help climbing hills or on the lower RPM area, will that be any better for performance in that range (low rpm range)?
Right now the 10 and 40 seems pretty good, I just thought 11/40 would be better and less stressful on the engine and drive components.
Please clue me in here

Thanks guys!

If you change only the front sprocket, you would have changed the ratio from 1:4 UP to 1:3.6464 so you won't be able to climb hills as steep, but you will be cruising on the flats at lower rpm than before.

You can get a 44t for the rear to keep gear ratio exactly the same but have less load on the chain. Put a 10% lighter chain on it and there should be a little less power lost in the drivetrain. Or beef up your engine.

I know that I would love to try an 11t.

 

[Deleted member 27811]