Final drive oil

My 2010 ST1300 has 4300 miles and I changed the Final Drive Oil for the first time. I was surprised by the amount of metal in the oil that was drained. There was a pea size amount of metal filings in the oil.
Is this normal?

No. When I changed mine (around 25K) the old oil looked clean. Well, it was clearly used, but there were no obvious metal shavings in it. Perhaps the stuff you found was debris left over from the manufacturing process? But there should be NO abrasive particles in the oil. Did you use a magnet to determine if they are steel or aluminum? I have no experience here, but I would pull the final drive off the bike (relatively easy to do) and open it up to see if there is any obvious damage. Obvious to my untutored eye.....

I have been riding shaft bikes since 2001. Old final drive oil has always looked its normal color at change time. Particles that large warrant a removal and inspection.

I was surprised at how much junk was in the rear end of my ST when I first changed the oil and cleaned the magnet on the drain plug. After a couple of changes with synthetic oil the rear end oil has never looked like the original oil. I now have over 152,000 miles on the bike and the rear end is still working fine. If I were you I would change the oil with some synthetic oil and keep riding that bike.

970mike said:

If I were you I would change the oil with some synthetic oil and keep riding that bike.

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+1

You should find that the drain plug magnet comes out virtually clean after using synthetic gear oil.

Good idea to go very easy on tightening that drain and fill plug(s). They are hollow and others have sheared them with overzealous tightening.

That's why there is a torque setting for both and an admonition to replace the rubber O ring every 24,000 miles. Torque to 9 ft/lbs for the fill and 14 for the drain. Besides the low torque setting on the fill another reason for damage is the O ring seal is never replaced. Over time it deforms and gives less resistance and "feel" when the fill plug is tightened.