I just discovered, while installing a NEW driveshaft in my '87 K75S that BMW had redesigned the drive shaft with a beefier universal. Thanks BMW.
When I went to slide the drive shaft through the hole in the end of the swing arm, I discovered that the new style universal is about .030" BIGGER than the hole in the end of the swing arm. THANKS BMW!!!
After calling both Cal BMW and Hansen's BMW, I was told that you have to remove the swingarm, install the driveshaft, then slide the swingarm over the driveshaft. They said that not only is it a real pain in the ass, but you must remove the swingarm every time in the future when you do a spline lube or not clean the whole drive shaft and forego lubing the front splines!!
After removing the swingarm I discovered that the universal will slide all the way through the swingarm except for the first 1" at the final drive end. Once the universal is near the tranny end, the swingarm bore opens up and there is no issue.
Since the ID of the hole on the final drive end does not locate anything (the dowel pins do that), I ground the hole at 12 o'clock, 3 o'clock, 6 o'clock, and 9 o'clock until the universal would easily slide in and out.
Yes, it's a little more work now but it will save me a ton of extra time over the course of all the subsequent spline lubes.
In the future, anyone installing a new style driveshaft in an older K-bike does NOT need to remove the swingarm (and peg plates, etc.). All you need to do is stuff the swing arm with a rag to prevent grindings from getting far inside. Then grind the hole at 12,3,6,and 9 o'clock so the universal easlily slides in and out. Then clean out the chips and the rag. The grinding will take WAY less time than removing the swing arm and make future splie lubes a snap.
I hope this helps someone else in the future.
Now I'm going to have myself a well deserved beer.
When I went to slide the drive shaft through the hole in the end of the swing arm, I discovered that the new style universal is about .030" BIGGER than the hole in the end of the swing arm. THANKS BMW!!!
After calling both Cal BMW and Hansen's BMW, I was told that you have to remove the swingarm, install the driveshaft, then slide the swingarm over the driveshaft. They said that not only is it a real pain in the ass, but you must remove the swingarm every time in the future when you do a spline lube or not clean the whole drive shaft and forego lubing the front splines!!
After removing the swingarm I discovered that the universal will slide all the way through the swingarm except for the first 1" at the final drive end. Once the universal is near the tranny end, the swingarm bore opens up and there is no issue.
Since the ID of the hole on the final drive end does not locate anything (the dowel pins do that), I ground the hole at 12 o'clock, 3 o'clock, 6 o'clock, and 9 o'clock until the universal would easily slide in and out.Yes, it's a little more work now but it will save me a ton of extra time over the course of all the subsequent spline lubes.
In the future, anyone installing a new style driveshaft in an older K-bike does NOT need to remove the swingarm (and peg plates, etc.). All you need to do is stuff the swing arm with a rag to prevent grindings from getting far inside. Then grind the hole at 12,3,6,and 9 o'clock so the universal easlily slides in and out. Then clean out the chips and the rag. The grinding will take WAY less time than removing the swing arm and make future splie lubes a snap.
I hope this helps someone else in the future.
Now I'm going to have myself a well deserved beer.
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