I recently picked up an 88 FXRS. It had a little K&N breather mounted on the transmission. I noticed the bike was getting covered in oil, coming from the vent/breather. I removed the breather and re-routed the line up in a u shape and back down under the bike to vent to the ground. The bike was still puking oil all over under the bike, and when parked it leaves a good puddle. I pulled the cam chest to check the breather gear, and it is a stock plastic gear, and everything was in good condition. No case scoring and the breather is timed correctly. I next tried to run the breather/vent line way up the frame and back down, thinking maybe gravity would help me with a longer line. It didn't do anything, and it's still blowing excess oil, to the point that people behind me are getting a mist on their bikes/glasses.
Bike runs out awesome otherwise, it's a got a SE-4 cam and Mikuni carb, but the top end "appears" to still be stock/original. (the bike rips actually, it will beat a 107 M8 without issue) I can still see cross hatching in the cylinder walls through the spark plug holes, and the pistons don't have much carbon on them at all.
Any thoughts or suggestions? I might order a steel breather and swap that in, but I don't have any confidence it will solve the problem.
Try running it straight dwn, that is the way mine is and works fine.
Someone B4 me jammed some air cleaner foam around it .
I clean it out once in a while.
Stop putting oil in it when it is cold
Correct nose cone gasket and or nose cone for 92 and earlier? Wrong ones will cause this.
Quote from: Racepres on June 28, 2020, 07:53:52 AM
Stop putting oil in it when it is cold
:agree:
However I have seen scavenge side of the oil pump strip the key causing oil to blow out. Debris like a lifter roller pin get sucked up and damage the gears.
MIKE
my 88 did the same thing, the steel S&S breather fixed it for me.
Quote from: MikeL on June 28, 2020, 08:12:12 AM
Quote from: Racepres on June 28, 2020, 07:53:52 AM
Stop putting oil in it when it is cold
:agree:
However I have seen scavenge side of the oil pump strip the key causing oil to blow out. Debris like a lifter roller pin get sucked up and damage the gears.
MIKE
More than once... Yes..
Quote from: ecir50 on June 28, 2020, 09:49:06 AM
my 88 did the same thing, the steel S&S breather fixed it for me.
Was the plastic gear Broken??
The engine does Not Know what the breather is Made of...Long as it is Functional, and timed..
no not broken must have been wore out. The S&S gear is slotted different than the stock unit which I suspect fixed my problem.
Some pics here
https://thunderpress.net/editorial/columnists/motorhead-memo-air-apparent/2018/10/23.htm
tdrglide may have hit on it. Be sure the nose cone gasket seals the window on the left lower side all the way around. You need to use the early nose cone and gasket. :wink:
John
Quote from: jsachs1 on June 28, 2020, 01:56:35 PM
tdrglide may have hit on it. Be sure the nose cone gasket seals the window on the left lower side all the way around. You need to use the early nose cone and gasket. :wink:
John
I'm betting I grabbed the wrong gasket from my stash... I'll pull it down and R&R and report back. Thanks guys.
When my '85 FXR did that...it was beacuse I had failed to keep that cute little KN filter CLEAN. It was totally clogged. I was on a road trip at the time. I took it off, threw it away, re-filled the oil tank and had no more problems.
That was 175,000 mi. ago. Haven't missed it.
It was the gasket. Thanks for the help. Runs amazing with the HSR42 and Dayton Twin Tech 1007 with custom curve.