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My engine oil breather has blown out a quart of oil in the last 1000 mi. I have BB kit and just put in a Barnett heavy duty clutch. Since the breather hose comes out from the clutch housing I'm wondering of I put a crimp in the soft metal part of the hose that's inside the case while putting the clutch cover back on. Maybe it's building up pressure. I'm just taking wild guesses. I'm not over filling it with oil but tried keeping it at the minimum oil line and that didn't help. I have been cruising between 70 and 80 mph. If blowing oil is the nature of the beast than I'll live with it but if not, I'd sure like to know what might be the cause. Any one have any ideas? Thanks.

Not 100% on your problem but my breather also blows out oil. Not that much but enough to notice. I was told thats just how it goes, esp. on hot days sitting in traffic and whatnot.

I was in a lot of heat and traffic jams during this trip. If thats the cause than maybe switching from 10w-40 oil to 20w-50 would help.

That sounds like a lot of oil for 1000 miles. Mine blows oil too, but it's not nearly as much since I ran a longer hose up to a filter under my seat. I can only guess you have an older model with the centrifugal type breather, apparently they have improved on that design but it can't be retrofitted to our engine casing or something like that...

Just to put your mind at rest get a compression gauge. Faulty/worn rings/cylinders will lead to increased crankcase pressure and blow-by. It's probably not that, but it doesn't hurt to check.

My bike started using about 1 qt. every 1000 miles right after my engine casing had to be replaced. It seemed to be the worst on continued highway travel. I made a couple of changes that cut consumption to about 1 qt. every 4000-5000 miles.

I started running the oil level at the bottom of the indicator (Triumph's suggestion). I also noticed that my breather hose had a slight dip in it. You do not want any way oil can collect in the hose. Oil that would normally run back down into the crankcase can collect and "burp" into the airbox. I cut about an 1" off the airbox end of the hose and reattached. These two steps did make a big difference.

Triumph did make a change from my original model which had a rotary breather. The newer crankcase (like I have now) is slightly larger on the breather side and has a different type of breather. Still, it seems like some sort of design flaw.

Thanks for the input. My bike is an 02 and the hose does dip. I'll change the hose and move the breather. I have the "freak" air box replacement kit so there is room to try different locations. Thanks again for the info.

EnglishYankee's solution:

I have twice seen the replacement of the breather tube seal fix an excessive oil consumption issue. On my bike ('02 model) and a friends bike ('03 model)
Part # 11 in this schematic...
http://www.bikebandit.com/showschematic/m17595sch565404