Towlieee

Is a 'clean air mod' even possible on a 600rr?? I've done it to friends bikes.. But just now I pulled a valve cover off a 03-04 600rr motor, and the 3 hoses on top of the crank case don't lead to anywhere inside

I always thought one connected to the exhaust? But I don't see how that's possible?

Also has me wondering if the clean air mod is the same on a f4i? Does it not really go to the exhaust? Am I just plugging up all the ventson the motor? Could this POSSIBLY be my oil pressure issues? Not allowing oil to pump easily???

Just wondering if anyone has actually cracked open the valve cover to inspect for them selves?

Also i've NEVER had oil burn in my exhaust on my f4i, EVER. Even after flipping my bike with the clean air mod

Towlieee

bump

I got the head off and don't see anywhere the vents could go

Going to pull the cover thats INSIDE the valve cover off, that leads to the vents, and see exactly what is going on in there..

ToKwik

Clean air mod is about the same as the 03-04 636. Plenty of threads about the 636.

It's not.

Please do not plug up all the vents on the motor. It will run worse.
And no, probably not related to your oil pressure issues.


Stock setup should be two lines coming off the top of the valve cover connecting to a central electronic pair valve that vents into the airbox.

Without the clean air mod, any excess oil in the top of the cylinder head gets vented through the reed valves, through the pair valve, and then back into the airbox. This excess oil gets mixed with the intake air and is run through the engine during the normal combustion process. The excess oil is burned off and exits the exhaust as smoke. Think of it as a crankcase ventilation system during normal operations. Normally, this system is just venting crankcase gases. But wheelies cause a buildup of excess oil in the top of the valve train that is not normally there. Remember, the bike is designed for straight and level operation.

The clean air mod takes this excess oil and diverts it around the airbox and deposits it directly back into the casing on the back of the motor. When doing this, it is recommended to either gut the electronic pair valve or remove it and replace with a plastic tee. Also recommended to cap off the two new holes left in the airbox as a result of removing the valve cover and case vent lines.

So, its pretty much the same as the 636's. Only difference if the bike is CA emissions equipped.

Hope that helps some.

Towlieee

:bang head

I understand what the clean air mod is, I've been doing it on bikes for about 3 years now

I'm just saying, you connect the 3 hoses on top of the valve cover, together, with a T connection... But the valve cover doesn't connect to anything, how does it physically get to the exhaust port from the top of the valve cover.

I'm going to go out in my garage right now and pull the plate off the inside of the valve cover and take pics and see exactly wtf is up

Towlieee

ok forget this thread, after complete disassembly of the valve cover I found the passages to the exhaust

skillz

so is this mod worthwhile on a 600rr

Towlieee

apparently

Three hoses on the top valve cover of a 600rr, middle one is a valve cover pressure release, outside 2 are connected to reed valves to the exhaust

old man roger

if i would have seen this thread earlier i could have saved you some time ...lol

but you figured it out on your own so it's all good

ToKwik

Sorry. All good.

Glad you got it figured out. Only had an OEM combo manual to reference for 600/636 and it showed no differences for the VSV and reed valves between the two models.

Towlieee

Don't chime in now after I wasted time and act like you know anything

old man roger

check all the clean air mod threads and see how many times i had to convince people that the two hoses were ported to the exhaust chamber via reed valves , there are always people telling me im wrong till they take it apart and check for themselves

old man roger

the crank case vent tube on an f4i is at the top left of the motor so the only time it will smoke with the clean air mod is after it's been lying on the left side rolled up on the tank and running or some times just from revlimmiters , the 636 has the crank case vent tube at the rear of the motor and low so it will get smoke if there is too much oil or if the bike is past 12 for a while

Towlieee

yeah yeah rub it in I understand now


I am surprised honda's don't have one at the bottom end, but I 'guess' the cam chains passage supplies enough pressure relief

I was looking at the damn valve cover last night lost, but soon as I opened the top caps I saw where the the vents ran

btw anyone looking I have a complete 03-04 600rr motor with supposedly 8.4k miles on it.. Friend purchased a mint 600rr with a blown motor, bike rides GREAT now whit a new motor, but the motor I pulled from it threw the 4th rod and blew 3 holes in the case..

Parting everything out!

edit: head in great condition