Timken conversion
Stage III
Joined: Jul 2023
Posts: 3
Likes: 0
From: Sweden
Thank you for the reply, but again: I'm looking to get a specific question answered, which you too failed to do in your response.
The question is:
In installing a timken bearing conversion, does the left side bore require trueing to bring it in proper tolerance of the right side?
The question is:
In installing a timken bearing conversion, does the left side bore require trueing to bring it in proper tolerance of the right side?
Road Warrior
Joined: May 2011
Posts: 1,956
Likes: 437
From: florida
Hello all,
Before responding please, ask yourself, "does my response include a fact based answer to the specific question asked?" If the answer to that question is no, please refrain from commenting. Opinions are great things, but that's not what I'm looking for today. If you don't know how to help, start with staying out of the way.
I was planning on doing a timken conversion on my 09' FLHTCU. Another rider I was speaking to said that when Harley went to the left side roller bearing they also began having the left and right case halves manufactured separately and as a result the left side bore is often not true and needs trued to the right side before the conversion can be done.
I hadn't heard this mentioned in the YouTube videos I watched or a few articles I read. So, naturally I wanted to check with some other folks on this.
Thank you for the feedback
bikerpiper
Before responding please, ask yourself, "does my response include a fact based answer to the specific question asked?" If the answer to that question is no, please refrain from commenting. Opinions are great things, but that's not what I'm looking for today. If you don't know how to help, start with staying out of the way.
I was planning on doing a timken conversion on my 09' FLHTCU. Another rider I was speaking to said that when Harley went to the left side roller bearing they also began having the left and right case halves manufactured separately and as a result the left side bore is often not true and needs trued to the right side before the conversion can be done.
I hadn't heard this mentioned in the YouTube videos I watched or a few articles I read. So, naturally I wanted to check with some other folks on this.
Thank you for the feedback
bikerpiper
HDF Community Team
Joined: Jun 2006
Posts: 12,763
Likes: 2,597
From: san antonio
Hello all,
Before responding please, ask yourself, "does my response include a fact based answer to the specific question asked?" If the answer to that question is no, please refrain from commenting. Opinions are great things, but that's not what I'm looking for today. If you don't know how to help, start with staying out of the way.
I was planning on doing a timken conversion on my 09' FLHTCU. Another rider I was speaking to said that when Harley went to the left side roller bearing they also began having the left and right case halves manufactured separately and as a result the left side bore is often not true and needs trued to the right side before the conversion can be done.
I hadn't heard this mentioned in the YouTube videos I watched or a few articles I read. So, naturally I wanted to check with some other folks on this.
Thank you for the feedback
bikerpiper
I was planning on doing a timken conversion on my 09' FLHTCU. Another rider I was speaking to said that when Harley went to the left side roller bearing they also began having the left and right case halves manufactured separately and as a result the left side bore is often not true and needs trued to the right side before the conversion can be done.
I hadn't heard this mentioned in the YouTube videos I watched or a few articles I read. So, naturally I wanted to check with some other folks on this.
Thank you for the feedback
bikerpiper
John Dahmer at Darkhours can answer the OPs question but I don't think the answer is a clean yes/no and at the end of the day, the OP will have to make the decision based on the build plan which the OP has not provided..
Last edited by djl; Jul 4, 2023 at 01:52 PM.
Seasoned HDF Member
Joined: May 2008
Posts: 21,031
Likes: 12,555
From: South Carolina
John Dahmer can answer the question (whatever it is) as long as he follows the OP`s strict guidelines for answering.
Last edited by Dan89FLSTC; Jul 4, 2023 at 02:00 PM.
Club Member
Joined: Mar 2009
Posts: 66,104
Likes: 51,370
From: Niles Canyon Ca.
FYI for everybody in here, Harley went away from the Timken bearing on the cranks as cost and time saving move on the production line. The current floating pressed together flywheel assemblies can be done by a fully automated process whereas the superior timken assembly takes more time and live bodies to assemble and check correctly. That said the technology for very accurate automated machining and assembly processes allow for this.
That's the bottom line.
As to the original posters issues, the crankcases are are line bored and honed as matched sets regardless of when or where the individual parts were made.
That's the bottom line.
As to the original posters issues, the crankcases are are line bored and honed as matched sets regardless of when or where the individual parts were made.
Stage III
Joined: Jul 2023
Posts: 3
Likes: 0
From: Sweden
Hello all,
Before responding please, ask yourself, "does my response include a fact based answer to the specific question asked?" If the answer to that question is no, please refrain from commenting. Opinions are great things, but that's not what I'm looking for today. If you don't know how to help, start with staying out of the way.
I was planning on doing a timken conversion on my 09' FLHTCU. Another rider I was speaking to said that when Harley went to the left side roller bearing they also began having the left and right case halves manufactured separately and as a result the left side bore is often not true and needs trued to the right side before the conversion can be done.
I hadn't heard this mentioned in the YouTube videos I watched or a few articles I read. So, naturally I wanted to check with some other folks on this.
Thank you for the feedback
bikerpiper
Before responding please, ask yourself, "does my response include a fact based answer to the specific question asked?" If the answer to that question is no, please refrain from commenting. Opinions are great things, but that's not what I'm looking for today. If you don't know how to help, start with staying out of the way.
I was planning on doing a timken conversion on my 09' FLHTCU. Another rider I was speaking to said that when Harley went to the left side roller bearing they also began having the left and right case halves manufactured separately and as a result the left side bore is often not true and needs trued to the right side before the conversion can be done.
I hadn't heard this mentioned in the YouTube videos I watched or a few articles I read. So, naturally I wanted to check with some other folks on this.
Thank you for the feedback
bikerpiper
i overhauled an 2006 engine. And that engine run great after the timken conversion. The flywheel set is of S&S 4 3/8 stroke. Everything true from left to right.
I am sorry I didnt now they changed the manufacturing later. Greetings Peder
Seasoned HDF Member
Joined: May 2008
Posts: 21,031
Likes: 12,555
From: South Carolina
The flywheel assembly was the failure point on the TC engines, not the left side (non tapered) roller bearings.
How many posts have we seen in regard to failed left side roller bearings?
How many posts have we seen in regard to failed left side roller bearings?
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Club Member
Joined: Mar 2009
Posts: 66,104
Likes: 51,370
From: Niles Canyon Ca.
Excess runout is the result of the flywheels scissoring, the pressed in crankpin relies on interference fit only hold both halves of the wheel assemblies true. Poor design and very prone to allowing the wheels to move.