Oil sight glass

[nick7]

I decided to design a 2nd breather after monitoring the crankcase pressure on a 180 degree triple on my test bench, I set up a 0-10psi transducer installed in the dip stick hole and ran the engine
Having been involved in drag racing in the past where they use Vacuum pumps to scavenge the crankcase cavity to gain horsepower I was interested to see what was going on

You could watch the gauge on the software go crazy, up to 6 psi fluctuation depending on revs whereas do the same on a 120 and the needle barely moved
Is caused by those 2 pistons going up/down and the poor old middle piston trying to keep up so I machined up and installed a 2nd breather bolted to where the Starter motor should be and which has a Kawasaki 125cc 2 stroke Reed valve inside of it
Works really well

I doubt that anyone else has ever taken the time to set up and record the crank case pressure on a Laverda triple
Shit you do when trying to find power out of these old clunkers

Wow, proper work! So it does seem to be the case that a 180 triple doesnt need to be sick to lose oil from the breather, even if not overfilled?Aim those breathers away from the rear tyre , gentlemen

 

[Vince]

When I first bought my 3c it came with a receipt for a rebuilt head, I didn't read the details as I wanted the bike regardless. A couple of weeks later it started blowing smoke out the breather and exhaust and occasionally would belch an egg cup of oil out of its breather right in front of the rear tyre. I guess that is a deliberate sign of warning, a bit like that deliberate water leak cars do when the water pump dies. Plumbers would run an overflow line from ceiling-mounted water heaters right over your front door just so you knew there was trouble happening. In my 3c case that rebuilt head consisted of just valve oil seals, not the actual guilds. After a full engine rebuild, I have had zero oil or anything else come out of the breather other than the necessary extra pressure. Anyway, a non-pressure sealing catch tank cannot hurt.