plus one,dont plumb fumes back into the oil filter,ive always shook my head at that design,pcv as used on cars and other bikes are ok,just not via the air filter.
I have written innumerous posts warning against that poor design. When I was about to begin doubting my own judgement, caused by the never ending opposition in this forum by some 'expert', I found confirmation in a testreview of the CB550F2 in the world's leading motormagazine,
Das Motorrad handed to me by a friend and... there it was. Testers had detected poor performance and in a joined effort with Honda Germany, they had traced it to the airfilter element being fouled by the blowby gas system.
BTW, in Holland it had already been common practice by both dealers as well as owners to cut the connection and have the breathertube vent into the open. Typical info the dealers would receive in their annual update meetings with Honda The Netherlands. Compare the difference in performance the Germans detected between the old (1976) CB500K2-G - with #78 main jets and airduct! - and the newer CB550F2 in the article below (p.8 third column). Shocking, isn't it?
There's a remedy however. If you
insist on running the original, either have the oillevel not higher than halfway the dipstick
or turn to imo inferior aftermarket foam filters which you have to clean. The 'expert' mentioned above has opted for the latter.
Glad the dispute has been finally settled now, after having to face over 15 years of opposition.
The 'expert' has always maintained his postion that Honda always knew best. Believe it or not, I tend to agree with him. It's only when the US interfered by forcing Honda to adapt the original design that things became worse. Much worse.
Are the American automotive industry and the US authorities highly regarded in the world outside the US? I'm afraid not. Their focus has always been on gadgets, things that only have to perform well in ads.
Here's a short list of 'succesful' products US consumers ended up with.
The dreaded headlamp-always-on-wiring.
More plastic used in bigger blinkers and taillights. Are they better noticed? Not at all. They're just bigger.
Childish gadget running lights.
Sit up and beg handlebars.
Cars with 17 (!) cupholders and only 7 seats (Dodge).
A 'sportscar' with - can you believe it?! - a solid rear axle and leave springs (Mustang). In fact: an ordinary Ford Falcon in just another coat. Millions sold! My goodness, in France even the cheapest Citroën 2CV (21hp) had a technical very advanced front wheel drive and independent suspension.