If you are thinking about upgrading the cams in your Twin Cam Harley or even if you are just taking it apart to service and or replace the chain tensioners, it is highly recommended that you change the factory bearing with a set of new Torrington bearings. The simple reason contains reliability and strength factors. The Torrington bearing has double the rollers of the factory INA bearing and the more rollers the smoother operation and longevity of the bearing.
We reached out to Bruce Tessmer from S&S for his thoughts: I suppose penny pinching is a factor, but you also need to look at the application. Stock cams and stock valve springs don’t put as much of a load on the cam bearings, so the stock bearings are adequate for that application. If you put in a performance cam with more lift, you increase spring pressure so the stress on the cam bearing increases, and of course with a performance cam, you will tend to drive it harder. It’s just human nature, but that too increases the stress. If you install some high lift valve springs and increase the spring pressure even more, you put even more stress on the bearings.
The stock bearings have spacers between the rollers to keep them rolling straight but there aren’t as many rollers. The benefit of using the Torrington bearings is that they don’t have spacers, just more rollers, so they have more load capacity. The load is spread out over a larger contact area. That’s why we recommend that the stock bearing be replaced with a full compliment bearing when installing one of our cams. Besides you should never install a new cam in the old bearing anyway!
Bruce Tessmer
Marketing Projects Coordinator
S&S Cycle Inc.
To prevent damage to the crankcase it is important to use the correct tools when doing this. I start off using JIMS Inner Cam Bearing Puller #993. The puller is designed to go through the bearing and catch the outer part of the bearing while not touching the crankcase.
Here’s the description from JIMS: INNER CAM BEARING REMOVER TOOL
No.993 – Use on all T/C, 2006-present DynaTM and 2007 FLHT & FXST.
No.1279 – Use on all Twin Cam, 2000-06 FXST, 1999-05 FXD, and 1999-06 FLs.
Next the Remover Body is installed over the puller with the bore towards the bearing. Apply a few drops of oil to the large washer and contact side of the nut and install on the puller. Slide the pin through the bore of the puller. The pin will prevent the pin rollers from accidently falling into the crankcase should the bearing come apart during removal.
Using a 1 1/8-inch wrench, tighten the nut until the bearing comes out of the case – NOTE Do Not Turn The Tool with the 5/8-inch wrench flat on the end of the puller. That is only used to keep the tool from turning if necessary.
Once the bearing is out of the crankcase remove it from the tool and repeat the operation on the other bearing.
Clean the bearing bores, lubricate the bearing with engine assembly lube. If lube is not available clean engine oil can be used. As you look at the crankcase bore you, will notice a thin lip at the bottom of it. I have seen people break this lip and send metal into the bottom end of the engine by using the wrong tool such as driver.
Hit it with a hammer just a little too hard and it is all over!
That is why I use JIMS Inner Cam Bearing Installer #787. It will work on all 1999 Twin Cams to present. Here’s the description from JIMS team:
No.787 – Use on all T/C, 1999-present.
Use this tool to press in, and install, the two inner cam bearings JIMS No.8991K. This tool has been designed to press from the letter side of the inner cam bearings, by putting all the pushing pressure to the very outer wall of bearing shell. Eliminates any damage to the bearings, cam and cases. This tool will stop at the case and set the bearing depth to .023 to .028-inch below the case surface. Use with JIMS Tool No.1279 to remove bearings.
With the lettering on the Installer Plate Facing you insert screw, put installer on the end of it, place the cam bearing on the installer with The Numbers on it Facing The Tool.
Turn in screw carefully until you feel the bearing enter the bore then tighten until the bearing seats. After removing the plate check that the bearing is 3.10-inch from the edge of the bearing to the cam cover face surface. Repeat for the other bearing.
Both the tools do come with detailed instructions to help you through the procedure.
–Rogue
