[DAVE H]

HI ALL
After going for a run for about thirty miles on my1970 cb450 there i quite a lot of oily petrol substance coming from the rocker breather pipe,i have the pipe routed to come out by the rear mudguard,so i find the chainguard,rear wheel,etc is covered,in oily substance,which almost smells like neat fuel,after the bike cools down the breather pipe has totaly dried,so appears to be more fuel than oil,the previous owner had put the breather pipe into the airfilter box,the bike runs well,with no smoke from the exhaust with good compression.
has anybody else had the same problem,dont really want to run the pipe onto the road as it might go onto the rear tyre,any help guys would be appreciated.
thanks
Dave.

 

[Bird76Mojo]

Have you performed a compression check? I'd advise doing one.

There shouldn't be that much coming from that hose. It's just a vent, not meant to expell anything but gases. So you've got a larger problem.

GB :mrgreen:

 

[66Sprint]

The fuel smell IS the clue..... Smell the oil in the sump as well...IF it also smells of fuel, DON'T run the engine, Change the oil immediately!.....Failure to shut the petcock off when parking , bad shut-off needles and/or seats, or float height problems are all possibilities.... FIX whatever is bad before riding again.... It does NOT take long to trash a camshaft getting lubed with thinned oil....

 

[DAVE H]

HI thanks for the info have just smelt the oil on the dipstick and yes it does smell of fuel,i have only had the bike a couple of months,she was flooding badly on the left hand carb,which i sorted out,so fingers crossed this could be the cause,will change the oil and try her again,so again fingers crossed.
Dave.