Topic: CB550 VFR800 stator swap questions

[purf_man]

so I had the parts laying around for awhile and finally found a guy willing to work on the machine work for me.  He has turned the first tapered sleeve but we need to trim it down thinner to suck the flywheel up closer to the cases still.

the question that was brought up is that 550/650 crank has no thrust bearing on it to locate the crank.  The VFR flywheel/windings have a fair amount of pull between them and we have a concern of the crank being pushed/pulled constantly to one side causing issues.

I know there aren't alot of people that have done this swap but maybe some insight as I am sure people here have good experience with these motors.

[dave500]

the end float on these cranks is pretty wide,its taken up by this ridge on the crank and the case itself on this machined pad,not real precision,i think a constant pressure will wear it out?i know those permanent magnets are bloody strong.

[purf_man]

he was talking about just shimming it and spinning until we get it true but wanted to know if we needed a better plan.

right now it is going to be a tight fit under the CB550 cover.

[dave500]

dimple the case pad to hold extra oil?

[purf_man]

I wish that the pad was wider so I could mill it down some and at least epoxy on a brass or bronze shim for a wear surface in its place...

well I asked him to see how close he can get the flywheel and maybe some work will be needed to get the thrust reduced as much as we can.  maybe I need to find a decent spring scale and measure it  so I can log it at different shim thicknesses and see if we can pretty much reduce it down to nothing.

[purf_man]

Would making an adaptor for under the points cover to hold a thrust bearing be an option?

I just am trying to figure out a reasonable solution that will make me feel better than "getting it close"

[dave500]

I think its getting over complicated now?

[purf_man]

ok so maybe I was trolling a little on the last post.

[iron_worker]

I wonder if there is a way that a guy could carefully grind a small channel from the main out towards the locating surface as shown in Dave's pic. This would hopefully collect oil that is coming out from between crank and bearing.

It would be tough though ... The groove edges would have to be perfectly smooth so you're not causing more wear than you're preventing. You'd also need to be real careful not to hit the crank journal ... obviously.

IW

[750essess]

Are you sure the magnets are still pulling on the crank with cover fully seated? On my setup you can pull the cover away a few millimeters before the magnet starts to pull. It floats in the center of the magnet.