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I will start with a clarification:
This 1968 xlch engine will not end up in a restored bike, but is being modified into a race engine to race in Period 3 Classic series.
I bought the bare cases knowing that they had some issues but......
The eBay seller's description of “a couple of small issues” has turned out to be a large understatement and he could consider cutting back on the crack pipe.
One of the smaller issues of the right case was the counter shaft bearing area being flogged out and beyond a bearing fit. I've welded this spigot in readiness for boring, but there is a lot more welding to be done to strengthen this area before I can think about boring the hole.
At this stage, some of you may scratching your head and wondering how a race engine has any place on a restoration forum.
I wanted to check if I had put enough weld in the repaired spigot before boring it.
The closed end bearing is an interference fit in the case.
I put three parallel bars on the mill table and snugged the cases down to it.
I needed to find the center of the welded spigot, and my plan was to use the trap door that I intended to use on the engine.
I decided to use the known areas of the case as zero “main shaft bearing” of the right case to check if the trap door lined up.
This is where I got side tracked from my original mission.
I put a dial indicator on the quill and lowered it into the main shaft bearing race, and zeroed the table readouts. I torqued the “performance” trapdoor into place and then put the dial indicator on the clutch gear.
The following table movements were required to center the shaft of the trap door; X. - 0:195” Y. - 0:165”.
There is no way a bearing is going to put up with this type of shenanigans.
I then decided to use an original trap door and do the same procedure:
X. - 0.050” Y. - 0.070”
This measurement is still beyond any sort of acceptable tolerance.
My point: Sportster owners piecing together an engine... beware of miss matched/miss aligned parts.
Regards Steve
This 1968 xlch engine will not end up in a restored bike, but is being modified into a race engine to race in Period 3 Classic series.
I bought the bare cases knowing that they had some issues but......
The eBay seller's description of “a couple of small issues” has turned out to be a large understatement and he could consider cutting back on the crack pipe.
One of the smaller issues of the right case was the counter shaft bearing area being flogged out and beyond a bearing fit. I've welded this spigot in readiness for boring, but there is a lot more welding to be done to strengthen this area before I can think about boring the hole.
At this stage, some of you may scratching your head and wondering how a race engine has any place on a restoration forum.
I wanted to check if I had put enough weld in the repaired spigot before boring it.
The closed end bearing is an interference fit in the case.
I put three parallel bars on the mill table and snugged the cases down to it.
I needed to find the center of the welded spigot, and my plan was to use the trap door that I intended to use on the engine.
I decided to use the known areas of the case as zero “main shaft bearing” of the right case to check if the trap door lined up.
This is where I got side tracked from my original mission.
I put a dial indicator on the quill and lowered it into the main shaft bearing race, and zeroed the table readouts. I torqued the “performance” trapdoor into place and then put the dial indicator on the clutch gear.
The following table movements were required to center the shaft of the trap door; X. - 0:195” Y. - 0:165”.
There is no way a bearing is going to put up with this type of shenanigans.
I then decided to use an original trap door and do the same procedure:
X. - 0.050” Y. - 0.070”
This measurement is still beyond any sort of acceptable tolerance.
My point: Sportster owners piecing together an engine... beware of miss matched/miss aligned parts.
Regards Steve
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