Commando 300090 report.

Not open for further replies.
May 22, 2004
Well after six months I am extremely pleased to report that my issues with the bike back in November remain ALL resolved.

The handling issue has remained rock solid.

The issue of dodgy fuel which I proclaimed wide and far were grossly exaggerated and since replacing the high a resistant and the other at the end of the day . open circuited ~ low tension cables.. the bike has never ~ failed to start and perform!

Now I don't replace the fuel every few weeks if I don't use it up and the bike fires within the first one or maybe two kicks at most !!!

And further more I can still loudly herald the positives of fitting the PVC valve to the engine breathing system ~ it has made and remains a real bonus ~
And there is absolutley bugger all oil on our garge floor.. I reckon Miss M's Toyota leaks more oil than my Commando ~
Good for you!
I remain a bit reserved but positive as to my judgement on the PCV valve...installed one early last week. Interesting effect, after the sump is pumped empty, the motion of air out of the tube gets quickly so reduced, at least at idle, that it is hardly detectable, seems like the volumn of air is quickly brought to a status that balances between the down and up strokes, thus no motion at the end of the did reduce the amount of leakage at the place in the cases that made me try a PCV valve, and after three hours driving last night, seems to be at the point that I can live with....maybe the thing really does work. Just so strange with the sound of the air gone. What with the new pipes, and the huffing and puffing sound gone, the bike sounds almost like it has had a sex will take me a while to get used to lack of roar.....but I guess Bob Dylan was not so wrong. The times indeed indeed may be changing.... :wink:
can you post a link relating to your "handling issues"?
i'd like to see what was going on and how you went about resolving it.

Re: ReCommando 300090 report.

What kind of pcv valve did you use? How was it installed? I have been thinking of installing one on my MK3 but I am unsure how to do it. Any info appreciated.
Sorry been flat out like a lizard drinking here.

What sort of PCV valve ~ (Where are you? ) I am an Ozzie and I took the PCV from a GM Holden engine which is quite large and suitable I felt for the job.

First it is best to fit the valve as close to the oil tank as practical ~ mine is sitting above the battery, at same level as the oil filler cap there abouts.

Depending what sort of valve you use of course, the hose may simply slip on.
Mine took a little adapting to seal up but no biggie ~

Found the results were obvious after the first outing.

I have seen them listed in a parts listing on the net as a kit.. but I can't tell you where now..
what valve did you use of the old holden, and which oil line do you put it in, is it the return or the intake or the breather hose, i have a 72 750.
The valve that slips into the back of the tappet cover, and leads off to the Brake booster ~

(It rattles a lot on the Holden engine if that helps.. on a XU-1 it is unbelievable just how much it rattles~lol All to do with the engine breathing capacity )

You splice it into the breather line from the top of the oil tank to the engine.

You have to establish which way is 'go' and the opposite ~ 'blocking'

SO ~ you put the valve into the line so that the air pressure is allowed to escape to the oil tank, BUT NOT suck air into the
the crankcase.
The theory , is that the crankcase pressure does NOT build up and put pressure on all the seals and gaskets which results in oil misting over the engine, particularly the lower crankcases !

I feel the result was/ is extremely positive ~ I found my first Trident T160 was really good overall as far as misting and leaking goes ~ but I plan on fitting one to the Trident T150V which I am building at the moment!
Well, since I am in the USA I have no idea what a Holden engine is. However, since a PCV valve is essentially a one way check valve I got to thinking about it and dug around in my tool box and came up with a neat little check valve that I had removed from the fuel system of an airplane. It lets fuel pass in one direction only but it must be mounted in the vertical position only so that the flapper inside of the valve will stay closed by gravity. Its volume is a little larger than most of the PCV valves I have seen. After a total restoration I am looking to start the engine tomorrow. I will let you know how things work out.
On the face of it I would have to say that it would be better to 'err' on the over-size than too small ~

As I suggested the idea essentially is to allow the pressure generated by two 'air pumps, the pistons, pumping downward on the air that is other wise drawn into the crankcase via the breather in its normal state ~ would otherwise create a pressure vessel within the crankcase.

I know that some engines in their original state were/ are lacking in the escape of this compressed air.

I guess you don't have to be a Rocket scientist to get the idea eh ..

(Oh the "Holden' in OZ is a derivative of the Chevrolet/ GM engines. )

:D It all works for me ~ :D
Not open for further replies.