Inner Primary Bearing

[Eglider05]

It looks to me where this is one thing HD got right, well close anyways. After previously using S&S races with the Harley bearing I decide to try the double row sealed bearing which eliminates the race. That was a mistake, it's shot after less than 10K. A few people are going to rightfully say "I told you so". Sometimes you just have to find out for yourself. I'll stick with tried and true in the future.

Rick

[TweekmyTwin]

Was that the Baker High Torque bearing ?

[Eglider05]

Was that the Baker High Torque bearing ?

It was an All Balls which is the same thing. http://www.phatperformanceparts.com/All_Balls_Inner_Primary_Bearing_Upgrade_for_Big_Tw_p/ab-25-3102.htm

Rick

[Admiral Akbar]

Actually it's not.. The Baker is only a single row.. messed up 1 of them in.. The All balls should be better as it is double..

I was hoping the all balls was better.

Max

[rbabos]

You guys realize all radial loads travel throught this primary bearing before getting to the trans? This is a tall order for balls instead of a wide roller. It also in my opinion that this crushes the theory of a tight primary chain screwing the trans bearings up. Has to get by the ip first. When I had the inner off to do the 120 I could detect play in the main shaft. Dial confirmed .002 total clearance. With the inner primary installed there was no detectable play in the main shaft. I've always thought the ball bearing replacement was not up to the task. Where the name (high torque) chit came from is a mystery to me.
Ron

[turboprop]

Interesting discussion on the the inner primary bearing and the thoughts on the single row ball bearings. In the transmission, both shafts ride on single row bearings at both ends, well except for the counter shaft left side. Have never see an issue with any of those bearings.

[rbabos]

Interesting discussion on the the inner primary bearing and the thoughts on the single row ball bearings. In the transmission, both shafts ride on single row bearings at both ends, well except for the counter shaft left side. Have never see an issue with any of those bearings.

Doesn't the main shaft run on two sets of rollers inside the sixth gear? The ball or main drive bearing does have issues now and then and no exact reason for this. The trap door bearing on the earlier six speeds were weak as well as the trap door. Baker 6f6 addressed that and I believe on the newer bikes both the bearings and trap door has been beefed up. This is more of an effort to keep the shafts from going in two differnent directions from helica cut thrust loads.  The lever effect of the trap bearings being so far away from drive torque loads allows them to live at this reduced radial load.
Ron

[turboprop]

For simplicity sakes, I will limit this to the 5 speed. I know most everyone now except for me has a six speed, but the five speeds are pretty straight forward. Two shafts, ball bearings on three of the ends, roller bearing on the fourth, half of the gears ride on roller bearings, all of the gears are strait cut. So, without any side thrust issues from helical gears, the single row ball bearings in five speed transmissions have proven to be pretty durable. Would you agree?

[Eglider05]

the single row ball bearings in five speed transmissions have proven to be pretty durable. Would you agree?

I dunno...... I trashed one on my 5 speed. When I replaced it is when I made the switch to the inner primary All Balls double row bearing. I was convinced it would be alright, but I guess not. S&S race with roller bearing for me.

Rick

[rbabos]

For simplicity sakes, I will limit this to the 5 speed. I know most everyone now except for me has a six speed, but the five speeds are pretty straight forward. Two shafts, ball bearings on three of the ends, roller bearing on the fourth, half of the gears ride on roller bearings, all of the gears are strait cut. So, without any side thrust issues from helical gears, the single row ball bearings in five speed transmissions have proven to be pretty durable. Would you agree?

I went from panhead to a six speed twin cam, so  , I have no personal experience with them, however what I've read on them, yes I would agree.  Now, to change things up a bit let's remove the ip bearing completely, just like the old panhead days with that long unsupported main shaft and slap in a 120r.  Pretty sure the bearing on the left side of the trans would be barfing it's balls out real quick. Might go a bit longer with rollers on the main gear and bushing for main shaft like the pan used but I think it would be overwhelmed soon enough. Only pointing out how much action and load this ip bearing really sees prior to the trans seeing this. Based on bearing area whether single or dual ball the roller wins hands down. You would have to agree in some warped way this makes sense?
Ron

[turboprop]

I completely agree with you. My interest in this learning and understanding, just as I assume for you. 

Just thinking out loud here. The street pro bikes are hovering around two hundred horse and run oem style trans and inner primary cases. Would be interested in hearing from Paul Morris what he runs in the inner primary in his street G2 126 and his SA SP bike.

[TweekmyTwin]

I guess I have been very fortunate because my Baker HT bearing has over 40 thousand miles on it.. and I do have a DD6 in there. I got lucky I guess
Jim

[turboprop]

I ran the narrow sealed bearing sold by Primo/Rivera for maybe eleven years without issue. Also have run the double row and single row bearings as sold by AllsBalls and baker without issue. These inner primary bearing debates are sort of like a taste great/less filling oil debate.

[pwmorris]

Just thinking out loud here. The street pro bikes are hovering around two hundred horse and run oem style trans and inner primary cases. Would be interested in hearing from Paul Morris what he runs in the inner primary in his street G2 126 and his SA SP bike.

Hey Buddy,
Running the S&S race on both bikes-
Also run a welded 1 piece front sprocket with no comp. Delkron inner primary. Ceramic bearing by World Wide Bearings. Keeps everything straight and tight. I don't like anything moving in there thats not supposed to be-
SP bike needs a primary chain replacement every 1-2 race weekends or test sessions depending on how many passes I get-they get kinked and are shot. If anyone knows a company that makes a super strong primary chain, it would be a great help-something that would last a while.
Also that bike primary is opened up all the time for inspection to make sure everything stays where it is supposed to.
G2 street FXR is overdue for full inspection as I have been ignoring primary but I'm finally putting in the Roberts' Trans and the new electric shifter set up that I was telling you about in the next couple weeks so it will get a complete upgrade with fresh clutch pack, etc...

[mariner227]

It looks to me where this is one thing HD got right, well close anyways. After previously using S&S races with the Harley bearing I decide to try the double row sealed bearing which eliminates the race. That was a mistake, it's shot after less than 10K. A few people are going to rightfully say "I told you so". Sometimes you just have to find out for yourself. I'll stick with tried and true in the future.

Rick

I'm wondering about the statement about HD getting it right (Inner Primary bearing)? Mine failed at 12k miles. 2010 flhtcu. I'm not the only one that had this problem. My dealer did not have the race or bearing in stock. I called around to other dealers and one dealer had 5 on stock. Others had several.

This proves that there is a problem with the inner primary bearing. Maybe I'm missing something!  I know that I've upgraded the motor but the same bearing and race are installed in all the SE 110's.

[Eglider05]

It looks to me where this is one thing HD got right, well close anyways.
Rick

I'm wondering about the statement about HD getting it right (Inner Primary bearing)? Mine failed at 12k miles. 2010 flhtcu. I'm not the only one that had this problem. My dealer did not have the race or bearing in stock. I called around to other dealers and one dealer had 5 on stock. Others had several.

This proves that there is a problem with the inner primary bearing. Maybe I'm missing something!  I know that I've upgraded the motor but the same bearing and race are installed in all the SE 110's.

I said close, the roller bearing is right, they just need to use a tapered race like S&S. I wouldn't use a HD race as they tend to walk into the tranny seal.

Rick

[mariner227]

It looks to me where this is one thing HD got right, well close anyways.
Rick

I'm wondering about the statement about HD getting it right (Inner Primary bearing)? Mine failed at 12k miles. 2010 flhtcu. I'm not the only one that had this problem. My dealer did not have the race or bearing in stock. I called around to other dealers and one dealer had 5 on stock. Others had several.

This proves that there is a problem with the inner primary bearing. Maybe I'm missing something!  I know that I've upgraded the motor but the same bearing and race are installed in all the SE 110's.

I said close, the roller bearing is right, they just need to use a tapered race like S&S. I wouldn't use a HD race as they tend to walk into the tranny seal.

Rick

Rick

Thanks for the information. I understand now. I'm carrying a spare stock race and bearing just to be safe. I'll pick up a s&s race.

[HDSlowride]

I haven't been on here in a number of years. Just a few times in the last 4-5 years but here goes. I have an '07 Ultra Classic, 103ci, Andrews 54 cams, 2 into 1 exhaust, huge air cleaner (SE cone). I pull a Bushtec on cross country trips. Factory oil cooler, of course. A bit over 72,000 miles on the clock right now.

Just put the third inner primary bearing in this damn thing. I put the 2nd one in last December and the first one a couple years ago. A wrench friend of mine says he sees it all the time in H-D's that are pulling trailers. I told him I pulled a trailer over 100,000 miles with an '02 Ultra Classic with never a problem. He says, "Yeah, but not with a six speed". I never have believed that pulling a trailer hurt one as much as a sidecar (I've done that too, with an Evo) or a trike kit. I asked him how H-D remedies this IPB on the trikes and he said the tranny was different (or the bearings or something).

So what do I have to do to fix this? Take out that stupid auto chain tensioner? Use different bearings? By the way, I see a lot of discussion about an S&S tapered inner race. What's tapered and how would a taper work with the stock roller bearing? Is it just the big chamfer on the end of the inner race that causes it to be referred to as tapered? Help me out here and let me know what the current thinking is on this subject please.

[divercal]

Hdslowride good questions in IPB and Tapered race and unfortunately no responses in almost a year.i can't see how tapering the race prevents anything.

[JohnCA58]

The only thing the tapered race does is prevent the inner race from moving in toward the main bearing by being tapered in the inside of the race at the end toward the clutch basket.

[rbabos]

One of the issues with IP life is the fluid used. Not so much the type but the amount of dirt in it. Considering the enviroment it lives in, it does pretty good. Tapered race solves one issue but not all.
Ron