Remove Harley Sprocket Shaft Bearing
Article by Mark Trotta
On Harley Panhead, Shovelhead, and Ironhead sprocket shafts, the inner bearing is a press fit. This article discusses several ways how it can be removed, as well as the tool(s) needed.
NOTE: To access the bearing, the engine needs to have it's primary drive components removed, so the left crankcase sprocket shaft and bearing cone/race is exposed.
As described in the old Harley-Davidson service manuals, the factory way to remove bearing from sprocket shaft is with a specialty tool. You can either buy one, make one, or modify an existing tool.
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Modified 2-Jaw Puller
By grinding down the claws on a two-jaw puller, they can be made to fit between the bearing and flywheel.
A bench grinder or hand-held electric grinder makes short work of this.
Shown in picture below; claw on left is ground down just enough to fit underneath bearing.
After you've trimmed the claws enough, you may have to remove the linkage plates from the puller and bolt the modified claws straight directly to the threaded body of the puller.
Not only does this method work, the puller can easily be assembled back to it's original form.
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DIY Bearing Puller/Removal Tool
The least expensive option is to make the tool yourself. If you can cut and weld, fabricating a sprocket-shaft bearing puller will cost you next to nothing.
This tool was fabricated by cutting a piece of 2" metal tubing in half, then welding on flat washers and a 7/16" SAE nut on the top. The bottom washer then gets trimmed back to clear the bearing race.
Materials required are a piece of 2" ID metal tubing, a 7/16" SAE nut and bolt, and two heavy washers.
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Buy The Tool
The Motor Company stopped selling these tools decades ago, so you'll be buying an aftermarket replacement from a company like Jims Tool or a cheaper non-USA version.
To remove inner Timken bearing from sprocket shaft on Big Twins 1955 through 2002, Jims part # is 1709. About $250.
For Sportster engines 1957 through 1976, Jims' part # 2305 removes inner Timken bearing from sprocket shaft. About $275.
Removing a sprocket shaft bearing is not a critical operation, so imported versions of these tools are cheaper and likely do the same job. You just won't be able to brag/complain to your friends that you paid $250 for a single-use tool.
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Author's Note: The first time I replaced one of these (many years ago), I didn't have the tool, so I cut off the old bearing and race with a cut-off wheel.
This is not recommended!
You have to be really careful and/or lucky - you can easily damage the shaft or the flywheel this way.
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Inspect the Shaft
Before installing a replacement bearing, check the mating surfaces of the shaft for scoring, wear, and grooves. If in doubt, replace them.
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Conclusion
If you are doing this job one time only, a lower-priced tool or a DIY tool are better options than buying the specialty tool. But if you're planning on working on other old Harleys, investing in a name-brand quality tool will get the job done quicker and easier.
As a last resort, you can go down to a local indie shop or machine shop and ask them remove the bearing. Expect to pay a minimum of $75 dollars for this service.
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What Is A Timken Bearing?
Harley sprocket shaft bearings are sometimes referred to as a 'Timken' bearing.
Timken® is a registered brand name, and they catalog thousands of bearings and races in all different styles and shapes. Since many vintage Harley-Davidson's were factory-fitted with this brand, it's often referred to as 'the Timken bearing' regardless of which year, make, and model it's in.
NOTE: Although they're based in the US, many Timken products are now being outsourced.
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