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Inner primary bearing failure

My thoughts lead me to think about a primary chain or drive belt too tight. That would certainly take out a bearing of the type being spoken about.

If you had a bad inner primary drive seal, you would discover that there is a surprising amount of oil supplied to the bearing area. I know this one 1st-hand. Finding the cause for an oil puddle under the scooter under certain conditions is how I know about that one.

The stock auto-adjusting primary chain tensioner, I believe, is a mechanical ratchet type. This type will not relax if it is ratcheted too tight, due to serious accel/decel event. A hydraulic tensioner is much better in this respect. It will relax, if it gets auto-adjusted too tight.

Care should be taken to ensure that the drive belt is not run too tight. This will likely take out the belt, as well as the innner primary bearing and the tranny drive bearing.

I have no 1st-hand knowledge here. It is just my engineering experience speaking, with respect to determination of cause.

Enjoy,
Rich P
 
On my 09 FLHR, when installing a new comp (se comp). Glad I could Not get the Original comp for the 09...

When taking out the old comp and installing the totally New comp and rotor, I had two choices... Grind a little relief on primary case bottom to Install the new SE comp. OR pull the inner case loose/off...

I chose the take it apart. Seeing the Heated Race behind the clutch THEN looking at the dimpled bearing in the inner primary.... Sure Glad I Caught that. No sounds YET were there (or I could not hear them)...

SO. IF you DO replace the comp. , I'd go the FULL route and check that under 25$ race and bearing... and I chose to use a new gasket also$.

I have the stock primary chain adjuster and have never heard it too tight. When apart it looked to be normal (good) tension and the shoe looked great yet... Repair done at about 55,000 miles.

I use Redline MTL in the Primary and doubt it to be from that.
(change with engine oil change)

The Primary's do GET Hot.... Especially in Az. 100+ heat.

signed....BUBBIE

Added:

I use Less belt tension than HD says to use....OLD SCHOOL
 
On my 09 FLHR, when installing a new comp (se comp). Glad I could Not get the Original comp for the 09...

When taking out the old comp and installing the totally New comp and rotor, I had two choices... Grind a little relief on primary case bottom to Install the new SE comp. OR pull the inner case loose/off...

I chose the take it apart. Seeing the Heated Race behind the clutch THEN looking at the dimpled bearing in the inner primary.... Sure Glad I Caught that. No sounds YET were there (or I could not hear them)...

SO. IF you DO replace the comp. , I'd go the FULL route and check that under 25$ race and bearing... and I chose to use a new gasket also$.

I have the stock primary chain adjuster and have never heard it too tight. When apart it looked to be normal (good) tension and the shoe looked great yet... Repair done at about 55,000 miles.

I use Redline MTL in the Primary and doubt it to be from that.
(change with engine oil change)

The Primary's do GET Hot.... Especially in Az. 100+ heat.

signed....BUBBIE

Added:

I use Less belt tension than HD says to use....OLD SCHOOL

Interesting point Bubbie. When discussing my concern with wrenchin/Glider/ Mr. Data, we discussed checking the tension of chain. I removed derby cover used a long screw driver and was able to move chain on top about 3/4 inch. He then suggested to check belt tension and like you mine is always on the loose side. I said to Harley manufacturing that, when will you do something or is it going to take a death before you proceed with a fix. Ironically the bad bearing noise is gone but there still is a slight bearing noise that is still there. the sound is coming from a different part of bike which I have not had the time to research out yet.... I have used nothing but Spectro since 1,000 mile service.
 
This part sits fairly high up in the primary case compared to where the oil level is... 3-4-5 inches. So, the part's lubrication it is fully dependent on splash up. Also, there is an oil passage hole (3/16") on the top side of the bearing seat housing to direct fluid down to the outer (transmission side) part of the race/bearing but since that was the side of the race with the most wear I'd say its not effective.

Right or wrong, I have countersunk the inlet side of that oil passage to make it more efficient. Not very deep but fairly wide (1/2") so its more like a funnel. Also I intend to apply general purpose grease on the new bearings during installation. Even if it all washes away from flow of primary oil to the area over time, I will feel more confidant that they wont be starting out unprotected. Jay

The grease might make you feel good but won't provide any real lubrication for the bearing as it will be gone a few minutes into the first ride. More important is the positioning of the retaining ring so that it does not block the flow of oil from the oil passage which, rightly so, you have modified.

I have seen the snap ring located so that primary fluid flow is impeded by the retaining ring. If the snap ring does not block the lubricant flow, you should not have this problem in the future.:D
 
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