Hi. I just wanted to add my experience with the one piece bearings available for twin cam bikes. Mine is a "04 touring bike, and I installed the bearing last year after my drive belt broke, just because I made a mistake when ordering the unit. I didn't know that there was an (upgrade) set up available and was trying to get a replacement set up just to do a preventive maintenance but when I got the package, the one piece set up was in there. I liked the fact that I could possibly take the inner primary apart to replace a belt without a special puller/install tooling if a belt broke while traveling at some point, so I tried it out. I removed the seals from the bearing before installing, as I read that some guys felt that would be the better approach. Now at about 4500 miles later, I recently heard some howling sound at about 50 MPH, in 3rd/4th gears. No oil leaking but I decided to pull the thing apart to inspect it in case there was an issue going on. I found nothing so far but the one-piece bearing is "notchy" feeling when I spin it with my fingers. The tranny shaft looks fine so nothing spun and caused damage at this point. I have another one-piece set up in saddlebag, and am considering using it WITH the seals in so I can get bike up and ready for a local bike run this next weekend.
I'm just wondering if the bearing might have lasted longer if the seals were left in, or if the bearings are just poor quality, or what. I have tried to research this but I'm just not finding any concrete testimonials of anyone that really has any solid understanding of this part and whether it can be a good mod or if not, why it isn't a good idea.
Anyone that would like to chime in, please do so. I would like to hear it! Thanks, nevadarider.

Just found this out: The (failing) one-piece bearing that was in the AllBalls kit is a KML bearing. I tried to check it out and I think that KML bearings are chinese bearings. OK--maybe that is the problem. I just ordered speed shipping on a Jim's one-piece set-up and it is supposedly made in the USA. Will try that!

 

Try the Baker bearing kit....They use a better bearing.

 

One piece sealed bearings are meant to be just that! They are manufactured with lubricant in them. I can't say whether the one piece bearings are better or not but leave it together next time.

 

Just an update. I read on an ad on amazon for the Jim's one-piece bearing kit. The ad said it was made in the USA, so I thought I would try it. When I got it yesterday, I looked at the bearing and it is the same as the one I just took out of my cycle. It does not say made in USA anywhere on the bearing, and I think it is the allballs kit, with the allballs label removed from the pkg. The bearing is marked KLM, just like the one I removed and I am pretty sure that it is a chinese bearing. There is a small disclaimer on Jims label stating that Jim's does not make that product. Anyway, after reading more on the subject and from suggestions made, I acquired the HD bearing and seal and an S&S race, and I'll begin installing that tonight.

Funny thing is that when I pulled the inner primary, the bearing felt notchy when I spun it with my fingers, and I was somewhat sure that it was the source of the howl sound I heard the weekend before (at about 50 mph). Now, after I pressed the bearing out of the primary, it feels smooth as glass when I spin it with my fingers. Hmmm. Hopefully that sound won't be returning with the new combination.

I looked at the S&S instructions for the race, and it states that I need to use their installer tooling, and am supposed to use the tool to push the race on the mainshaft to reach 35 foot pounds. I have a generic installer tool and am thinking I need to push the bearing on until I reach that 0.1 inch measurement from the 5th gear nut, same as the stock race. Hopefully that is correct.

Well, I guess I better shake off the weariness from the week of work hustle and get to it (yawn). Later!

 

The Baker kit uses an NSK bearing, I use their wheel bearings or Timken bearings in my Kenworth truck and they are equal in quality as far as I'm concerned.

That press on race is a piece of crap that can't possibly do anything but cause problems because it's impossible to keep it from moving inward and coming in contact with the main shaft seal and causing it to fail.
I will never run the stock style inner primary bearing on any motorcycle that I own again.

 

Well, here is what I found out during the install. The S&S race is not supposed to be able to move inward on shaft like the H D race and when I used my install tool I was getting close to the required 0.1 inch distance from the nut/seal and the race just stopped right there. I could feel the tooling tension up and it was apparent that if I tried to force it any further, something would have broke. I'm not sure what exactly causes the race to stop but it did and I'm sure it isn't going to "walk" in any farther. If the Baker bearing would have been a good way to go, that would have been okay with me. I'm going to get back in there after this season to do some other work, maybe I'll try one then. I'll finish up in the morning and hopefully she'll be ready to ride into that sunset that's awaiting.

 

The S&S race has a tapered shoulder which causes it to stop when you hit that shoulder. If you had continued to push, the bearing would have heard a crack about like a .22 rifle shot and the bearing would have split; they are very brittle. That 35 ft. lb. spec is misleading and trying to achieve that spec has cracked many an S&S bearing. As long as the race is on far enough for the seal to seat against the race, it's all good. Personally, I prefer the inner race setup and have not had issues with the OEM replacement race, bearing and seal.

Some have had good luck with a one piece bearing and seal from NAPA; both made in the USA. Bearing is and SKF bearing (PN 6205-2ZJ and seal (PN 692325). The bearing usually needs some honing on the race with a brake cylinder hone to get the right fit on the main shaft and I understand the seal can be hard to find but those that have used them have reported good results.