I recently installed a Rivera Primo Pro Clutch on my 1999 FLHTCUI (Ultra Classic) and was impressed with the clutch performance, but decided to add the TPP (centrifugal lock-up assembly) to improve the feel and performance even further. I ran into a snag in the installation, however...when it came time to adjust the clutch and tighten the lock-nut on the adjusting screw, I found that the hole in the middle of the TPP assy is too small for a standard deep well socket to fit. The nut is recessed into the TPP enough that it is impossible to get anything but a socket on it.
Has anyone else encountered this problem? Does anyone have any suggestions where I might find a wrench that is deep enough and has thin enough walls to tighten the lock nut? Is there another solution I am overlooking (maybe a smaller nut with the same inside diameter and thread...)?

 

As a follow up, I finally figured out how to adjust my clutch, but not in the conventional method. I went to Harbor Freight, Pep Boys and Sears before I found a deepwell socket that was the same size as the small one I knew would fit the nut and fit inside the slinger hub. When I got home I discovered, much to my dismay, that the socket I got at Sears, even though it looked exactly the same diameter as my original, would not fit. I got out my micrometer gauges and found that it was about 5/1000 of an inch larger in diameter. And it was the thinnest walled deep well socket I could find.
The way I ended up adjusting was:
1. I assembled the clutch and TPP and tightened down the bolts to compress the spring.
2. I loosened up the clutch cable and started screwing in the adjustment screw until i met light resistance then backed it off a half turn.
3. I tightened up the cable and squeezed the lever to verify proper lever travel and clutch pack seperation and made sure the clutch was fully engaged when released.
4. I used a small screwdriver to turn the locknut down to meet the pressure plate snugly.
5. I removed the slinger plate bolts and carefully took the slinger plate and spring off of the clutch pack.
6. I inserted a hex wrench into the adjusting screw to hold it in place and used an open end wrench to tighten the locknut.
7. I reattached the spring and slinger plate to the clutch pack, tightened down the nuts, and double checked that the clutch lever still had the proper travel and the clutch pack had sufficient separation and engagement.
8. I tightened up the clutch cable locking nut and slid the boot back over the adjuster.
9. I bent the retaining tabs over to secure the nuts holding the slinger hub.
10. I put the primary chain case cover back on and torqued the bolts to the proper specifications.
11. I put the plug back in and filled the case with Redline fluid to the bottom of the clutch spring.
12. I put the derby cover back on along with the recommended spacer and new screws (stainless hex cap screws obtained from Busy Beaver, 1/4 inch longer than the originals). note: the gasket that came with the spacer was too small on the inside diameter, so I had to use an old gasket cut to the right size to prevent counter-weight interference.
13. I started the bike up, made sure I heard no banging noises from the primary chaincase, and tested the clutch by nudging the bike back and forth in its stand in my garage.

A lot of steps, but without a proper sized wrench, the adjustment had to be done with the primary cover removed, not just the derby cover. It seems to work ok, though. I will find out for sure tomorrow if the rain holds off!

 

First... I know this post is years old so don't get your panties in a bunch because I bumped it. Someone using google search may find this helpful

If you use a 5/8 spark plug socket, it will fit and most have flats on them so you can use a 3/4 wrench to tighten. Just put the socket on the nut, put the allen wrench through the middle, adjust the screw and use the wrench on the socket to tighten the nut while holding allen wrench stationary... easy peasy.