Transmission main shaft
Elite HDF Member
Joined: Jun 2006
Posts: 3,698
Likes: 11
From: Longview, Washington
That's exactly my question to Baker. I would think it has to be a slip fit, otherwise the process of pressing it onto the mainshaft at the same tiime the primary is installed could potentially side load the bearing. My concern with the slip fit though, is having the bearing spin on the mainshaft under load. Once that happens the mainshaft would loose tolerance and be toast.
I tried calling earlier today but couldn't get a person. I'll try again tomorrow.
I tried calling earlier today but couldn't get a person. I'll try again tomorrow.
Extreme HDF Member
Joined: Sep 2005
Posts: 11,615
Likes: 50
From: Baton Rouge, LA
HD made an update to the inner primary (mainshaft) bearing. I believe the early bearings (06 dynas and 07 touring) had faulty (soft) inner bearing races. I also believe that HD knows this and is waiting out the failures without saying anything. Too many have failed at low mileage IMO.
I thought the Dyna primary-bearing failures were a result of the lack of alignment dowels near the bearing in the early '06's, updated about mid-year.
Your auction link for the primary-bearing tool no longer works. Do you have any other info on it like a current auction? That would be a good reference in case it's needed in the future, but let's hope it isn't.
This thread shows that there was an update to the mainshaft and bearing in late 07, early 08. My 07 had the updated bearing and when I ordered the bearing from the 07 parts book, it was the wrong bearing. I did some research and came up with the updated bearing.
Road Warrior
Joined: Jun 2008
Posts: 1,602
Likes: 3
From: Southeastern Michigan
My Inner Primary Bearing is in perfect shape, and now that we're talking I like the way that bearing is designed. However I'm thinking of going with Baker because of ease of use.
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,625
Likes: 6,442
From: Honah Lee
Lets make this perfectly clear? Ha
One problem I am still having here is you have what Harley call the main transmission shaft that comes out of the transmission thru the main drive gear shaft. The clutch hub and clutch basket attach to this and drive its rotation from the engine primary chain back thru the transmission and from there thru the gears and back thru the main drive gear that comes back out of the transmission and this is what the rear drive belt pulley attaches to. Were I am confused is when you look at my attachment were is the inner bearing for this and what type of bearing is it? Also you have the pushrod coming thru the main transmission shaft that activates the clutch. Is there a seal on this shaft or is this what the oil slinger is for? I always assumed the oil slinger was to help lube the transmission.
Last edited by Jackie Paper; Sep 14, 2018 at 10:26 AM.
Road Warrior
Joined: Jun 2008
Posts: 1,602
Likes: 3
From: Southeastern Michigan
Ok - here's the scoop from Baker on the their Inner Primary Bearing kit:
It is a slip fit (about a .001 clearance) and is shielded both sides. It can be lubed by the primary oil by pulling off the inner shield (towards the clutch). Comes with a separate outer seal.
It's benefits are "will not walk on mainshaft", unlike the stock bearing that can walk on the mainshaft race, potentially causing bearing failure? Don't see the logic on the walking, but I think I'm going with it anyway, for the same price of a stock bearing, and I won't need to buy the race installer tool.
He also said he hasn't had any problems with it spining on the mainshaft.
Now I'm waiting on F.A.G's input on the Main Drive Gear Bearing.
One more thing, the stock inner Primary bearing on my 07 is an INA bearing.
The engineer I spoke to yesterday manufactures both INA and F.A.G bearings though.
Still waiting on a return call from him.
It is a slip fit (about a .001 clearance) and is shielded both sides. It can be lubed by the primary oil by pulling off the inner shield (towards the clutch). Comes with a separate outer seal.
It's benefits are "will not walk on mainshaft", unlike the stock bearing that can walk on the mainshaft race, potentially causing bearing failure? Don't see the logic on the walking, but I think I'm going with it anyway, for the same price of a stock bearing, and I won't need to buy the race installer tool.
He also said he hasn't had any problems with it spining on the mainshaft.
Now I'm waiting on F.A.G's input on the Main Drive Gear Bearing.
One more thing, the stock inner Primary bearing on my 07 is an INA bearing.
The engineer I spoke to yesterday manufactures both INA and F.A.G bearings though.
Still waiting on a return call from him.
Elite HDF Member
Joined: Jun 2006
Posts: 3,698
Likes: 11
From: Longview, Washington
I installed a new chrome inner primary cover which came with a new bearing and seal installed. I chose to be lazy and not remove it.
BTW, this bearing is not my problem any longer . . . I traded my 07 for an 11.
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Seasoned HDF Member
Joined: Mar 2010
Posts: 38,625
Likes: 6,442
From: Honah Lee
Lubrication
I assume if you had replace you primary chain with a belt this bearing would be used sealed. Did Baker man suggest since you still have an oiled primary what was best way for you to use bearing as sealed or with front seal removed?
Road Warrior
Joined: Jun 2008
Posts: 1,602
Likes: 3
From: Southeastern Michigan
The bearing is shielded, which is different then sealed.
Shielded = metal shield, which keeps larger debris from entering bearing. It would still allow some oil in.
Sealed = rubber or rubber/steel, which is intended to keep out most debris including dust and water.