Originally Posted by rockymountainhi
, I did not remove the idler, but I did see the slot. I removed the drain bolt and used a flashlight to look as best I could see. Also I threw the bike around as much as I could to see if I could get it to move around some if it was in there. I also swept around with a long hooked pick but never did find it. I figured it may have just been left out when it was assembled at the factory or fell out as it had the stock Doo and spring so I don't think it had been opened.
Should I tear it back down? Or maybe get ahold of a magnetic drain bolt? I am pretty certain it was not in there but not sure if I'll ever be certain unless I find and remove one... Thanks for the help.
Unfortunately, odds are that the Woodruff key made it's way thru that slot, down into the sump. There's a similar slot on the RH side of the engine, but the clutch cover (and water pump) have to come off to to access that. There are baffles in the case bottoms that complicates things a bit, but sweeping the sump bottom with a small magnet usually does the trick. I use E-M magnetic drain plugs, but doubt that'd ever catch that Woodruff key.
PD mentioned a little trick, peening either side of the Woodruff key (with a centre punch) before reinstalling it into the slot on the crank - that works well (I've done it a few times building up KLR engines).
Sometimes that Woodruff key will stick to the (magnetized) flywheel/rotor on removal, but in my experience, when it inadvertently gets pushed out, it usually tinkles to the bottom (can hear it happening).
Here in this pic, you can see that I fished out a doohickey spring thru that clutch side slot I'm talking about. I found that spring MIA when I removed the flywheel on an '08 (with only around 6,000 miles on it) to do the doohickey mod - I could actually see it laying in the bottom of the sump, looking thru that slot with a strong flashlight.
Edit - there are more openings on the RH side of the case, that allow you to see into, and access the bottom of the sump, but more disassembly required!