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Discussion Starter · #1 ·
Hi.

This might sound a little odd, but what colour should the gearbox oil stay?

For example, if I put in some golden coloured engine oil into the gearbox, and then went for a 30-40 mile ride, should it still be golden when I check it through the sightglass?

I have heard that 2 strokes can sometimes seep a little bit of fuel into the gearbox, and thats why you replace it every 6 months or so.....

Is this correct?
or maybe I have a got a small leak?

Also, does it hurt the gearbox, if a tiny amount of fuel seeps in?

Thanks
 

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should change it in line with your manual. going in gold it should come out not far off the colour it was. obviously there will be particals in there but shouldnt be milky or anything.

petrol will thin the oil out.
 

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Whatever you do, don't make the mistake I did...

I assumed that my sightglass which was black was black because of oil in there. In actual fact it was black because it was covered in sh*t, and there was no oil in my box at all. No wonder my gears felt weird for a bit!
 

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Who said anything about getting it out? It just wasn't there!
 

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there is a 12mm bolt head behind the brake pedal,whip that out mate, but if you have acces to a paddock stand, use one, as the bike leans away from the drain hole, so you wont get all of the oil out if you leave it on the sidestand to drain.sometimes good to use an engine flushing agent, but check first that it is suitable for wet clutches, as most are designed for cars, so would never touch the clutch.the danger is,that the additive could make your clutch pads swell and go soft.

cant remember what brand i have used in the past, but ill try and find out for you, for tomoro
 

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my tzr had oil in for many thousands of miles

it was black when it came out.

it ran like a totally different bike when it had new oil.

all the previous owners must've been morons.

i only put 3k on it but changed the oil twice and it went in golden, and came out golden!
 

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Discussion Starter · #9 ·
I will know for definate tomorrow, but it didnt appear milky or anything.

There are a few particles in it but I think that might be a bit of the old oil.....

I think a tiny bit of oil is seeping into the gearbox though...it does seem to be thinning out a little....

My mates RS125 thinned his oil out....it seeped into the gearbox slowly......
he just changed the oil every 3000 miles and it seemed fine......until he ploughed it into a hedge at 75mph! 11000 he had done on it, and he then crashed it!

So is it normal for a little bit of petrol to seep into the gearbox?
 

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there is no actual gasket on the gearbox split,just gasket goo, so it is quite possible to get a little bit of seepage on an old engine
 

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Checked mine after reading this topic. Nothing in the site glass whatsoever!
I filled it up and now the gears feel silky smooth almost to a point where it changes gear a bit too easy. After a quick ride the site glass was later down again to 3 quarters. Is this normal?
 

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the oil has been spread among the various components of the gearbox, and it takes time for it all to drain back down to the level you filled it to.if it has been really low, then it may need topping up once it has been run,but dont worry, if it is going down too quick, unless it has a puddle under it when you go out in the morning!
 
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