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My new Ducati Scrambler Classic is fast becoming one of my favorite motorcycles. In stock form though, it has a number of “issues” that I want to address - the first being a gearing change.
The stock gearing on this bike is biased toward acceleration, making the “scram” a hoot to ride around town (wheelies galore!) but a bit buzzy on the highway. After riding mine for a couple of weeks I've decided the stock gearing is too short for my purposes. I'm willing to trade raw acceleration for lower engine RPM’s at higher speeds.
One of the nice things about having a bike with chain & sprocket drive, is that it makes changing your gearing ratios so easy. This is usually accomplished by changing out either the front or rear sprockets (or both). Fitting a sprocket with more teeth on the front will make the gearing “taller” - less teeth “shorter”. On the rear the opposite is true - bigger sprocket means shorter gearing, smaller results in taller.
The stock sprocket sizes for the Ducati Scrambler are a 15 tooth front and 46 tooth rear. As I wanted taller gearing, I either had to fit a larger front or smaller rear. Usually, the easiest way to accomplish this is to just change out the rear sprocket, as it entails less labor to do so - but since the Scrambler is a new model, my options there were limited. Most of the rear sprockets that are available right now, and would fit made of hard-anodized aluminum instead of steel - not ideal for someone like me who rides a lot of miles - so I elected to change out the front instead. The other bonus in this particular situation is that the stock chain length can be used without any alteration.
After consideration, I decided a change in the front sprocket from 15 teeth to 16 teeth would benefit me the most. Here is an image illustrating the RPM’s of this bike using the stock gearing...
And another, showing the changes with fitting a 16 tooth front sprocket...
To perform this modification, you will need to procure a replacement sprocket - Driven Racing is usually my vendor of choice for this, their part number for a 16 tooth front sprocket - which is a proper fit for the Scrambler - is “1067-520-16T”.
You will also need access to the following tools and shop supplies:
The first step is to loosen the rear axle nut and back off the chain tension. Use the 30mm socket for the axle nut, with a breaker bar - it is torqued very tightly, then the 8mm socket or wrench to loosen the chain adjusters on both sides of the swing arm.
After this is finished, remove the front sprocket cover using the H5 bit to remove the 3 bolts as shown...
While it is possible to change this sprocket without removing the left-side passenger peg support rail, it is difficult. Taking the extra 5 minutes required to do this is HIGHLY recommended,
To do this, first remove both the linkage bolt to the shifter assembly and the bolt attached to the exhaust CAT, using the H5 hex bit at the locations highlighted in RED, then using the H8 hex bit, remove the 2 bolts at the locations shown in BLUE.
Before doing so, I hope you are using a rear stand - or other suitable means - to support the bike. The side stand is going to come loose when you remove the larger bolts!
Next, remove the bolt bolt shown below using the 24mm socket. You can then slide the passenger peg rail off and out of the way.
Next, remove the 2 bolts on the front sprocket retaining washer, then rotate the washer slightly to line up with the splines on the counter-shaft and remove it too...
Now... slide the sprocket off the shaft and replace it with the new 16 tooth version. Re-install the original retaining washer, using red loctite on the 2 bolts.
As you can see for the following picture, there may be a clearance issue at the locations shown in red, below...
The black plastic part highlighted in blue in this picture is just a cover with some sealing o-rings - apparently this area was for a hydraulic clutch actuator used on other bikes that utilized the same motor.
I removed this “plug” to show the detail - you do not have to remove it.
You may, however elect to remove some material on the side of the boss the this plug covers - to alleviate the lack pf clearance highlighted earlier. I took a die grinder and removed less than 1/32″ from the upper area (the lower I left alone). Clearance issues may vary on your particular bike due to manufacturing variances.
To finish up, Install the passenger peg rail in reverse order of dis-assembly using blue loctite on all fasteners.
Then fit the plastic sprocket cover with the 3 bolts using blue loctite.
Re-tension and realign your chain - then re-torque the rear axle nut - and you can go out for a ride.
I think that this is a significant improvement for this particular bike. I’m no longer reacher for “7th gear” at higher speeds, and there is much less shifting at lower speeds, while just tooling around.
Originally posted on my personal blog @ www.moto-graphic.com
The stock gearing on this bike is biased toward acceleration, making the “scram” a hoot to ride around town (wheelies galore!) but a bit buzzy on the highway. After riding mine for a couple of weeks I've decided the stock gearing is too short for my purposes. I'm willing to trade raw acceleration for lower engine RPM’s at higher speeds.
One of the nice things about having a bike with chain & sprocket drive, is that it makes changing your gearing ratios so easy. This is usually accomplished by changing out either the front or rear sprockets (or both). Fitting a sprocket with more teeth on the front will make the gearing “taller” - less teeth “shorter”. On the rear the opposite is true - bigger sprocket means shorter gearing, smaller results in taller.
The stock sprocket sizes for the Ducati Scrambler are a 15 tooth front and 46 tooth rear. As I wanted taller gearing, I either had to fit a larger front or smaller rear. Usually, the easiest way to accomplish this is to just change out the rear sprocket, as it entails less labor to do so - but since the Scrambler is a new model, my options there were limited. Most of the rear sprockets that are available right now, and would fit made of hard-anodized aluminum instead of steel - not ideal for someone like me who rides a lot of miles - so I elected to change out the front instead. The other bonus in this particular situation is that the stock chain length can be used without any alteration.
After consideration, I decided a change in the front sprocket from 15 teeth to 16 teeth would benefit me the most. Here is an image illustrating the RPM’s of this bike using the stock gearing...

And another, showing the changes with fitting a 16 tooth front sprocket...

To perform this modification, you will need to procure a replacement sprocket - Driven Racing is usually my vendor of choice for this, their part number for a 16 tooth front sprocket - which is a proper fit for the Scrambler - is “1067-520-16T”.
You will also need access to the following tools and shop supplies:
- Size H5 Hex Bit
- Size H8 Hex Bit
- 24mm Socket
- 30mm Socket
- 8mm Socket or Wrench
- Blue & Red Loctite
- A suitable rear stand or other mens of supporting this bike (other than just the side stand - more on this later)
The first step is to loosen the rear axle nut and back off the chain tension. Use the 30mm socket for the axle nut, with a breaker bar - it is torqued very tightly, then the 8mm socket or wrench to loosen the chain adjusters on both sides of the swing arm.
After this is finished, remove the front sprocket cover using the H5 bit to remove the 3 bolts as shown...

While it is possible to change this sprocket without removing the left-side passenger peg support rail, it is difficult. Taking the extra 5 minutes required to do this is HIGHLY recommended,
To do this, first remove both the linkage bolt to the shifter assembly and the bolt attached to the exhaust CAT, using the H5 hex bit at the locations highlighted in RED, then using the H8 hex bit, remove the 2 bolts at the locations shown in BLUE.
Before doing so, I hope you are using a rear stand - or other suitable means - to support the bike. The side stand is going to come loose when you remove the larger bolts!

Next, remove the bolt bolt shown below using the 24mm socket. You can then slide the passenger peg rail off and out of the way.

Next, remove the 2 bolts on the front sprocket retaining washer, then rotate the washer slightly to line up with the splines on the counter-shaft and remove it too...

Now... slide the sprocket off the shaft and replace it with the new 16 tooth version. Re-install the original retaining washer, using red loctite on the 2 bolts.
As you can see for the following picture, there may be a clearance issue at the locations shown in red, below...

The black plastic part highlighted in blue in this picture is just a cover with some sealing o-rings - apparently this area was for a hydraulic clutch actuator used on other bikes that utilized the same motor.

I removed this “plug” to show the detail - you do not have to remove it.
You may, however elect to remove some material on the side of the boss the this plug covers - to alleviate the lack pf clearance highlighted earlier. I took a die grinder and removed less than 1/32″ from the upper area (the lower I left alone). Clearance issues may vary on your particular bike due to manufacturing variances.
To finish up, Install the passenger peg rail in reverse order of dis-assembly using blue loctite on all fasteners.
Then fit the plastic sprocket cover with the 3 bolts using blue loctite.
Re-tension and realign your chain - then re-torque the rear axle nut - and you can go out for a ride.
I think that this is a significant improvement for this particular bike. I’m no longer reacher for “7th gear” at higher speeds, and there is much less shifting at lower speeds, while just tooling around.
Originally posted on my personal blog @ www.moto-graphic.com