December 29, 20205 yr Author Another update, bike starts and rides lovely however after a short test ride, I came to a stop and when I put it in neutral there was an audible hiss and now it's p****** oil out of the crank breather. Any ideas anyone?
December 29, 20205 yr 6 hours ago, Backerlee said: Another update, bike starts and rides lovely however after a short test ride, I came to a stop and when I put it in neutral there was an audible hiss and now it's p****** oil out of the crank breather. Any ideas any Is there a breather on the crankcase ? Gearbox breather ?
December 29, 20205 yr Author There's a clear tube I'm assuming comes from the crank case or gear box and thats the oil source.
December 29, 20205 yr It may be the right hand main bearing seal is failing and pressurising the clutch basket side of the caseings, the hole that feeds the breather pipe is behind the top of the clutch basket. I had a sherco 125 chucking out oil from the breather it wasn't hissing though, that sounds like a complete seal failure. It may not be thow as I was always under the impression that the seals were to stop the crank sucking oil in and not the other way around.
December 29, 20205 yr A good test is to attach a longer pipe to the breather pipe, warm the bike up put the pipe in a bucket of water and if it bubbles like crazy when you rev the bike your main baring seals have worn-out.
December 29, 20205 yr Author The hiss was one brief noise as I put the thing in neutral it hasn't hissed since but that was definitely the start of the leak. I'm thinking a seal somewhere but haven't the faintest idea where
December 29, 20205 yr Author It would definitely bubble if I put it in water cos it's bubbling as it's forcing oil out
December 29, 20205 yr Did you fall off the bike and the bike end up landing on its right hand side for a while, as the gearbox oil could pool in the clutch side then get sucked in the breather hole as you stand the bike back up straight and carry on riding. there is a small cavatiy behind whare the breather attaches to the caseings if that has filled up with gearbox oil it might spray oil out for abit until its cleared, I used a vacume pump to clear mine.
December 29, 20205 yr Author No but if I shake the bike about a bit ie push down on the front end hard the drip gets faster if that helps
January 11, 20215 yr Try running the breather to a small transparent catch tank of some sort, maybe a large fuel filter or something, se how quickly it fills up. Mount it higher than the breather outlet then the oil will run back in to the gear box if it fills up the filter in mins you definitely have a air leak if its just abit of spatter you probably have to much oil in your gearbox.
January 11, 20215 yr Author I've definitely got a leak of some sort, I've been informed its probably the crank seal wet side which I understand is not an easy fix
April 28, 20215 yr On 1/11/2021 at 9:25 AM, Backerlee said: I've definitely got a leak of some sort, I've been informed its probably the crank seal wet side which I understand is not an easy fix Did you get it sorted? If you changed the oil before your last ride and added more than 450 the excess may be pumping out the breather hole. Keep us posted on progress. Cheers.
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