What causes an inner primary bearing to go bad?
Thread Starter
|
"Seeker of Freedom"
Joined: May 2007
Posts: 1,093
Likes: 2
From: Kansas City Area
What causes an inner primary bearing to go bad?
I see quite a few threads that mention inner primary bearings going bad. During the installation of my SE120R engine kit the tech said the only abnormal thing he discovered was the inner primary bearing was showing signs of wear at 15K miles on an 09 street glide. I don't want that to happen again if I can do something to prevent it.
What are the causes of an inner primary bearing failure?
What are the causes of an inner primary bearing failure?
Last edited by itsaw0rkinpr0gre$$; Dec 15, 2010 at 02:57 PM.
Elite HDF Member
Joined: Apr 2008
Posts: 3,900
Likes: 4
From: way down upon the Suwannee River
Mine went out at 30,000 miles. It's acually the transmission main shaft bearing. some just call it the inner primary bearing. From what I saw and was told it's the inner race that goes bad. (roller bearing) I went with a fully synthic heavier oil in the tranny and have had no more problems with my 08 going on 70,000 miles.
Elite HDF Member
Joined: Jun 2006
Posts: 3,698
Likes: 11
From: Longview, Washington
I see quite a few threads that mention bad inner primary bearings going bad. During the installation of my SE120R engine kit the tech said the only abnormal thing he discovered was the inner primary bearing was showing signs of wear at 15K miles on an 09 street glide. I don't want that to happen again if I can do something to prevent it.
What are the causes of an inner primary bearing failure?
What are the causes of an inner primary bearing failure?
I have a theory that the bearing design is the issue. Either that or the metal isn't hard enough on the bearing race. I do know that there was a change in the bearing and mainshaft in late 07. I found this out when I ordered the bearing for my 07. Here's the story . . .
I ordered the part # out of my 07 parts book. The bearing I received did not fit the mainshaft. I researched and found that there was an updated part # for the bearing and race. The new bearing race had a slightly smaller ID meaning the newer mainshaft was actually smaller. I suspect that HD went to a harder bearing race or higher quality bearing. Just a guess.
Here's a picture of the two different bearing races. Note the bad spot in the bearing race on the right.
Road Master
Joined: Nov 2008
Posts: 1,066
Likes: 4
From: Central Coast CA
from what I understand the bearing itself has a nonmetalic component in it. It is the bearing keepprt if you will don't know the correct term at the moment but you have the outer portion of the bearing the ball bearings and the inner race and then the bearing keeper retainer or what ever it is call around the bearings themselves. This is the component that is failing and allowing the race to walk out of the bearing and along the shaft. I will be going in soon myself how to do the SE comp, inner priamary bearing, clutch plates and a variable pressure clutch spiong assembly.
There is talk on another forum in regards to the compensator and what fluid you are running in the primary. Many have used ATF and other primary fluids but it seems that HD Primary + may be the right fluid. The others work well for clutch perfomance but may lack in in oiling bearings and the compensator.
There is talk on another forum in regards to the compensator and what fluid you are running in the primary. Many have used ATF and other primary fluids but it seems that HD Primary + may be the right fluid. The others work well for clutch perfomance but may lack in in oiling bearings and the compensator.
Outstanding HDF Member
Joined: Mar 2008
Posts: 2,456
Likes: 11
From: PacNW; Beacon of Conservatism in a Sea of Liberals.......AZ Snowbird; Just another Conservative
We '06 Dyna owners have had our issues with failing IPB's. In our case, I believe the problem is the lack of 2 alignment dowels btw the IPCase and Tranny Case. After mine failed twice (4K-mi, and 12K-mi), they replaced my -06 part number cases with the -06A cases (with 2 alignment dowels)...over 26K now, and no issues.
In our case, H-D gave early purchasers a "pink letter" stating they were conducting an "Initial Care Program" that amended Owner's Manual service intervals for primary/tranny lube, and allowed free IPB replacement every 15K-mi. (see letter below). Though they sent out a rescission letter later, the cat was out'a the bag regarding the pink letter being a de facto admission of a problem with the '06 Dyna.
I don't think the Touring cases lack the alignment dowels like the Dynas. Many Dyna guys are just replacing the stock IPB with the heavy duty "Baker Bearing", instead of going thru the channels to get H-D to replace the cases with the dowelled ones for free.
In our case, H-D gave early purchasers a "pink letter" stating they were conducting an "Initial Care Program" that amended Owner's Manual service intervals for primary/tranny lube, and allowed free IPB replacement every 15K-mi. (see letter below). Though they sent out a rescission letter later, the cat was out'a the bag regarding the pink letter being a de facto admission of a problem with the '06 Dyna.
I don't think the Touring cases lack the alignment dowels like the Dynas. Many Dyna guys are just replacing the stock IPB with the heavy duty "Baker Bearing", instead of going thru the channels to get H-D to replace the cases with the dowelled ones for free.
Thread Starter
|
"Seeker of Freedom"
Joined: May 2007
Posts: 1,093
Likes: 2
From: Kansas City Area
So you are suggesting that using the 20w50 synthetics in the primary may be contributing to the failure of these bearings?
Trending Topics
Tourer
Joined: Apr 2010
Posts: 251
Likes: 0
From: Australia
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider
Verdad Gallardo
Club Member
Joined: May 2008
Posts: 2,095
Likes: 4
From: Ponchatoula Louisiana
The bearing and seal failed at 25,000 miles on my '08 FXDC. According to tech and parts guys this is an all too common issue since they changed from Timkin bearings. Transmission had to be practically rebuilt under warranty. I would not attempt this job myself until warranty expires. I would think that all you need is a bearing puller and installation driver. If there are metal shavings and chunks, it's time for a rebuild. Cheap azz Chinese bearing.
Grand HDF Member
Joined: Sep 2009
Posts: 3,807
Likes: 283
From: Green Country Oklahoma
I had mine replaced at 22k under warranty and was told by HD tech to switch to good syn gear oil and since then 56k on it no issues. I use red line gear oil in both our bikes it also helped keeping trannys ltl quite.