Crankcase Breather

[Semper Gumby]

Hi Guys,

I'm getting oil in the square airbox which ends up on the bottom of my left carb where it drips onto the shift lever and my foot on my 03/1980.  I have the old style breather: Circlip washer spring washer and fiber plate.  

The assembly is pressfit into the case next to the starter.  Has anybody change this out for the new style reed breather.  Will this fix the problem or am I chasing my tail here and need to look elsewhere?

If this is the right direction, what is the best methord for getting out the old breather and putting in the new?

TTFN,

[Rob Valdez 79 R65]

I was not aware the "old style" (round disk that could move vertically on a spring-loaded post - if I guess correctly) was in use when the R65's were made.  Mine came with the read-type.


I got rid of the oil on my boot by routing the crankcase vent to atmosphere.

[airhead]

Changed mine out on the 90 for the reed conversion;


Did this by rigging a crude slide hammer and hooking it under the spokes of the old poppet valve. Did this with each spoke in turn till it worked it's way out.


Bill..................;-)

[thrang]

Although I've not done the mod on the RT, on the Bimbo I drilled out a hole at the back of the air box opposite the inlet for the breather and simply extended the breather tube so it vented under the bottom bracket.

[Semper Gumby]

Bill    That is inspired.  And I have a hammer head just sitting on my workbench!  Did you heat the case first or just give it a whack or four?  Darn - I don't think I have a heavy enough spoke.  Time to go to General Hardware.  

Wait a minute - if I do I might just buy the right tool for the job (where is the fun in that!) [Gratuitous Casual Tool Acquisition]

So by omission I guess concensus agrees that the reed valve will cure the problem?  (Oh please....)

thrang - I have contemplated putting a hose out the side of the airbox through one of the now three unused holes in the airbox.  I may yet do this if there is too much blood involved with Bill's solution.

[nothing]

So by omission I guess concensus agrees that the reed valve will cure the problem?  (Oh please....)

Sorry, but no the new valve will not solve the problem. We all deal with it, regardless of valve type. On my bike (with older style airbox) the oil doesn't make it as far as the carbs, but rather drips down the sides of my tranny.

The best solution I have heard of is to put a bit of material inside the breather housing to give the oil something to condense on, then it will drip back down into the engine. I've heard a metal pot scouring pad suggested, or any metal mesh will do (although I'd stay away from something as thin as steel wool, I'd think the thin bits of steel might break down with the heat and end up in the intake tract.)

You may have to go to the new style valve for this to work, however, since I think that the older valve might be impeded in it's operation by anything in it's housing space.

I like the tube to atmosphere suggestion, too, but my bike smells like oil enough already - that would make it a lot worse, I think.

[airhead]

Bill    That is inspired.  And I have a hammer head just sitting on my workbench!  Did you heat the case first or just give it a whack or four?  Darn - I don't think I have a heavy enough spoke.  Time to go to General Hardware.  

It was a welding rod I used, and though I applied heat to the area with a heat gun, I felt the heat sinking ability of the case made that a pointless exercise. It was barely above ambient when I pulled it out, though I've heard others have used heat from a flame, but it still came out without problems. The spokes on the old valve are pretty robust for all intents and purposes.
The only reason I changed it was 'cos I could and the reed replacement is cheap, and also it gets rid of the turkey gobbler sound at idle. Anybody want a perfectly serviceable poppet valve???
Ignore the fancy hook shape at the end, it was just me bending frantically a strong piece of rod that didn't want to bend too easily, into a shape that would fit the spaces between the valves spokes, and that's how it ended up!! LOL

Bill......................;-)

[Semper Gumby]

Well I was going to build the hammer impact puller today but instead I decided to show off the BSA Firebird instead and get a new trip odo reset knob (to replace the one that vibrated out of the known universe ).  On the way home the Firebird tried to kill me buy unscrewing a the retaining collar inside the front wheel hub.  The wheel then went on walkabout on the front axel and came to rest against the left front fork.  The nave plate sat and chewed on the fork tube while two fender bolts up top made parmesan cheese out of a brand spanking new Avon.  I made it home and then when pushing the bike around realized what a baaaad bike the Firebird had been.  Needless to say I was distracted.  Perhaps tomorrow....

[dewjantim]

I have replaced 2 of those old valves with the new ones. It did stop that gobble-gobble sound. If the old valve is worn out it might help your oil problem, or it could be something more serious like rings or leaky valve guides. On one of my BMWs I put another hose on the breather tube and extended it to the carb horn. It cured my problem. Don't think I would want to put anything in the airbox, afraid the carbs would ingest it or it would cut down on air intake......Dew.