Hi all, just a quick question as it's baffling me .. My gas gas is running sweet as a nut but gear oil keeps dropping ... I keep topping it up every second ride to half the sight window on flat ground and after two rides it's just a bottom of sight window .. I am oiling bike when stone cold each time .. Wheres the oil going .. There are defo no leaks as the bike lives indoors on wood floor and theres never a drip between rides.

Thanks

Hi all, just a quick question as it's baffling me .. My gas gas is running sweet as a nut but gear oil keeps dropping ... I keep topping it up every second ride to half the sight window on flat ground and after two rides it's just a bottom of sight window .. I am oiling bike when stone cold each time .. Wheres the oil going .. There are defo no leaks as the bike lives indoors on wood floor and theres never a drip between rides.

Thanks

With no leaks noted, one would suspect an inner crank seal allowing trans oil to be sucked into crank area under vacuum (especially if you noticed an unusual amount of smoke from the exhaust). I would always look at the simple things first, that being the trans breather (I'm assuming this is a Pro). It's the small right-angle fitting and hose in front of the countershaft sprocket (the hose goes up and loops under the tank), be sure that it is clear, otherwise pressure can build up in the trans casing and force some oil past the crank seal lip. Excess trans casing pressure symptom is usually weeping from the outer seals but not always. The crank seal is vunerable due to the normal pressure differentials it encounters.

Jon

Like I said Jon its running sweet ...baffling.. No smoke fro exhaust .. Could it be a major issue

I had gearbox oil being drawn past transmission side crank oil seal on my CR500 MX and it made no noticeable difference to performance. Oddly enough the ignition seal which runs with less lubrication was not leaking.

What ratio are you running it at ? If it's 80:1 your probably running at equivalent of 50:1.

Have some faith , my Trusty 240 Fantic loses oil ... And it doesn't leak a drop . She does smoke a wee bit , so when I get around to it , the cases get split and she gets new seals , But until it gets real bad , it's just on the to do list . And that's a long list !

Glenn

I run it at 70;1 and she's not smokey at all with fuel screw 3 turns out .. Oh well just got back from a three hour ride and to be honest the bikes never ran better ..thanks guys