Crankshaft dimensions.

It's 30mm. There should be a slight interference fit. I've just mic'ed up the timing side on an 850 crank and I get between 30.005 and 30.034.

30mm = 1.181". 30.034mm = 1.182". Yours seems a little on the large side.

Crank drive sides often come out a little large where the journal meets the taper. Don't know why, perhaps the journal had a little wear. Measure the journal as close to the crank cheek as you can, if there is a bit of a step you can give it a careful touch with some emery.

David, 

Your journal is way too big. It will take some time to reduce that down. 3 thou is a massive difference when trying to fit a bearing race. 

Looking at bearing manufacturer information, e.g. https://ntnamericas.com/wp-content/uploads/2020/03/brgfits.pdf#:~:text=For%20bearings%20under%20rotating%20loads%20or%20direction%20indeterminate,bearing%20loads%20or%20vibration%20and%20shock%20load%20conditions.

I'd say the inner race interference should be about 0.03mm or about 0.001" (on diameter). The bearing's running clearance will be excessively reduced if you force the inner race onto an oversize shaft which can result in premature failure.

I was suggesting that you might try to reduce any step on the journal that lies outside where the bearing would properly sit and might be making the race difficult to install. I would not recommend trying to reduce the actual journal with emery as it needs to be done with some precision.

Where does one get a new crankshaft these days?

I agree with Stan,  Bearings can get " notchy" if fitted  too tightly , I ruined a couple of box bearings because they were too tight in the housings ,  Bracebridge St 's old machinery problem I think. Easyist solution to emery the outside of the bearing  to ease the fit , not so easy to get the housing corrected. I have eased  cranks to fit  the inners of bearings using emery with care. Ducati bevel motors run on zero axial clearance so very difficult to get right with too tight fits.

Any specialist repairing cranks should be able to easily rectify the oversize journal. Emery would do it if it was close, but it's not, 4 thou is worth grinding off. 

Have you spoken with the crank supplier? From what is published in this thread, seems to me that it is "not fit for purpose" and should be replaced or repaired at their expense.

As a side point, did the bearings come from the same supplier? 

If those journals at that far off then what else is wrong on a new crank. Once you rectify those journals you own all the other unseen faults.

... it looks way out of tolerance. The finish on that bobweight looks a bit iffy as well. Where did it come from? I'd be getting my money back as it's clearly not fit for purpose.