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Well, this is strange. I took the bike for MOT today (wiped the oil off the stanctions up the road from the MOT centre and crossed my fingers). Got thru MOT ok.

Went for a ride and NO OIL LEAK!

This is strange.

I had a good look at the forks when I had them to bits and there is no obvious damage, but I guess there must be somewhere.

I'm gonna take the forks to a dealer and have them checked.

If they are u/s I guess I'll be in the market for a pair of second hand 750SS forks (dual disk).

Any advice?:(

It may be that some of the fork oil has crept inbetween the seal and the dust seal when you re-assembled the forks.I had exactly the same happen to me when I changed them on the wife's Monster.I went for a little test ride and spotted oil weeping down the slider.Stopped and wiped it off,then carried on.It never leaked again.

Looks like it is sorted
 

Seems it's sorted - you may be right keefyboy.

Just in case I took BOTH forks to bits on Sunday (between WSB on telly) and changed the oil for 10W and slightly lower level. I noticed that the oil in the "old leg" (the one that never leaks) was dark red and VERY thick compared to the 7.5W silkolene I had been using. Anyway - all reassembled, all oil tight. For now.