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Rode to work this morning and upon arrival discovered about a teaspoon of oil sitting on top of the rear master cyl cover. I felt up behind the side cover and there was a little up there but right now I am unable to pull the cover or get under the bike to look. No other visual or performance related symptoms. Bike ran fine and gave no indication it was bleeding until I saw the oil.
Can anyone speculate where this might be coming from based on the info? Trying to get a jump on it so I can target troubleshoot as soon as I get home. This is going to eat at me all day.
Note:
2006 XL1200C
6300 mi +/-
Syn3 everything
Rear master cyl on 2006 is on left side below battery cover. Oil tank is on right side.
There are 3 ports on the bottom of the oil tank. The feed, vent and return. The feed hose routes oil from the feed port at the lower right front corner to a fitting on the oil pump. The return hose comes from the oil pump back to the return port on the tank. The vent hose vents out the bottom of the frame. You should check the hoses and tightness on the clamps.
Thanks for the feedback. Got pulled away from the keyboard for other stuff so delayed response here.
Anyway, appears to be that I had oil blow out from filler/dipstick cap. That ran across seam in oil tank (plastic on the new Sporties) and finally dripped down the left side onto the brake cyl when the bike leaned that way. My guess is this happened when I left that morning. I didn't give it a lot of time to warm up before hitting the Interstate.
I'll wipe it down and keep an eye on it to make sure but it looks like a false alarm.
There is an oring on that cap that seals it. Check that. Also the cap fits into a double slotted keyway and turns clockwise and downard to lock into place and then pushes in. Make sure you have the cap turned in there correctly one of the slots is narrow and one is wide. My $.02.
This resurfaced again. Same deal, a little oil appeared on top of rear brake cyle cover. I pulled the side covers and there is oil around the cap. The O-ring is intact and present (stock cap replaced with temp gauge though). No evidence that any of the hoses are leaking.
I'm going to hit it with Simple Green tomorrow (wash day) and recheck for leaks. I am pretty sure this is due to my getting up to speed (65+) before oil temp gets above 100 degrees. Return pressure is greater than pull and results in overflow in tank. The commute to work is only about a 3-4 mile trek. Barely have time to get the choke in all the way before I get there.
I just need to give myself a few extra minutes to warm up before leaving home. We'll see for sure tomorrow.
I just got mine back from the dealer after the 5th time looking for the same oil leak. They finally found it was leaking through the starter. A seal in the starter was letting primary oil leak in to the starter. It would drop off the starter and run back to the master cylinder area. Just a place for you to look. Mine is a 2005 sporty.
GLewis
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I am new here and just recently bought my first Harley, a 2006 XL1200C and am having the same problem. Oil was low, barely above the low fill mark so added just enough to bring it comfortably above low mark yet below mid way. Started leaking at cap. When I checked the oil when hot it was still below the full mark, yet after inspecting and cleaning cap, o-ring and other areas I was still getting "blow by" around the O-ring.
My solution was to get a larger "metric" sized o-ring and replace the original with it. Barely leaks at all now but am worried that back pressure may cause some other problems. Can any here give an opinion on solution or potential problems? Is the cap supposed to be completely sealed or is it designed to "breath" a little?
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