Noob - Rebuilding Aprilia Rotax 122 Engine

[Djaniero]

Hi guys,

My Aprilia MX stopped working last weekend - running majorly low on gearbox oil. I'm guessing I have done some damage to the box, but won't know until I take the engine out and strip the gearbox down.

I was thinking while I'm at it and have the engine out, would it be a good idea to replace the piston and barel etc while I'm there for peace of mind or not to bother?

I have some basic tools at the moment, and a haynes manual, but is there a specific list of tools I would need to rebuild the engine?

Thanks

[bikenut]

in what way did it stop working??

I assume the eng was pushing out clouds of smoke??

any oil leaks ??

drain oil, how much came out and any metal flakes or metal bits come out.........pic of engine.......you have a manual and any special tools needed like flywheel puller ( and experience ) etc...........any exploded views of the engine to help you in the manual section on here........... :karma:
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[Djaniero]

I was riding along as normal about 20mph, no strange noises or anything, and the bike just cut out and stopped working. I tried to kick it over with the kik start, but almost as if was stuck, and wouldn't kick down. (I have since realised that the oil lubrication was flashing on the dash, so I assume it was telling me I was running low on gearbox oil)

No clouds of smoke, and no oil leaks strangely enough.

I took off the gearbox drain plug off and no oil drained out .I could see only a drop of oil inside the box.

I haven't seen any exploded views of the engine on here, but I have found a couple of tutorial videos on youtube.

https://www.youtube.com/watch?v=lZj2_R5TdtU

https://www.youtube.com/watch?v=LF42Sh8cIPo

ps - a couple of people said to try putting some oil in the box before I strip it down, but I'm bothered I may damage it even more trying to start it again??

[Scootaloo]

Yes, trying to start it could damage it... but its already damaged!

Just try some proper oil In there and leave it to soak for a while, then give it a go? Citation needed.
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[Djaniero]

Does it matter if it synthetic of fully synthetic oil? The owners Manual says 75w 90 but unsure which to use.

[Scootaloo]

[Djaniero]

point taken .

Just reading through the owners manual and realised something....I actually haven't taken off the drain plug its the filler plug I removed

If I remove the drain plug and I can see bits of plastic bits floating around in the oil, its safe to say that the box is screwed?

[Scootaloo]

[Djaniero]

Thanks, I'll get on the case the evening and keep you posted

[Djaniero]

Quick update. Just drained the gearbox oil...around 500mls worth came out. I can t really see any metal or plastic shavings in the oil but there were some tiny bits of metal on the magnet of the drain plug.

Is the normal or do the metal bits suggest something has gone in the box?...the oil has seen better days...dark green...i m guessing its most probably never been changed.

[Vincent]

Are you sure it's not two-stroke oil that's ran low?
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[P.]

[andy_uk]

[Vincent]

OP...a word of warning - if you end up employing someone to work on your engine, make sure they know what they're doing before handing the bike over

If it's just the top end it shouldn't cost too much to put right. Try searching on here for "RS125 rebuild" or similar.
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[Djaniero]

There is still plenty of 2t comp2 oil in the bike lads. When you turn on the ignition the 2t oil light stays on. But as soon as i started the bike it went off.
The lubrication light that was flashing was on the digidash, so i assumed it was the gearbox oil warning light?

I m going to try and do the work myself, but if I get stuck i have a good mate that is a honda mechanic whonis happy to help. Or would I be best giving it to a 2t mechanic?

[Vincent]

[Djaniero]

Lol...there was no other way i could word that without sounding like the typical my mate who thinks hea a mechanic lol.

Hes been working on my cars for the past 7 years, as i dont trust garages as far as i can throw them. So i trust his judgement when it comes to mechanics.

I'll double check again with him, but if he isnr comfortable doing the work, he'll be honest and tell me so

[Carvel]

Lol

Did you not realise the 2 stroke needed topping up?
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2002 Aprilia RSV1000R, Cbr600Fs, Mk1 B12, Vfr400 NC30...

Matt B: I can deal with crushed nuts to beat Ollie.

[evoboy]

Oil light on the dash will be 2 stroke oil warning.

Itll want a new cylinder and piston no doubt.
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APT Motorcycles

[Djaniero]

The 2 stroke tank was about 3 quarters full when it happened.

If I was running low on 2t oil, wouldnt the main oil light on the dash stay on?

[Ariel Badger]

Take the head and barrel off, they will be paper-weights. With luck your con rod will not be bent and your big end, small end and mains and seals will be ok. When you have rebuilt it stick to premix.
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[Kickstart]

Hi

No gearbox oil level warning light on those engines normally, and with a 2 stroke likely to be a 2 stroke oil level light.

Stripping the top end of the engine is pretty easy. Stripping the bottom end is not, and you will need various special tools to split the cases, and to reassemble the cases without pre loading the main bearings.

All the best

K
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[Djaniero]

I have read this before...i.e. people sticking to premix. Whats the benefit of doing this over having a seperate oil and petrol tank?

Thanks for confirming this for me kickstart....was getting a bit confused. If my engine has seized up, wouldnt my rear wheel have locked up - happy it didnt as the car behind me would have wiped me out

Also if I do need to split the case, what specilist tools will I need?

Thanks

[Kickstart]

Hi

The benefit of premix is that you are not reliant on the pump. But personally I have never had a pump fail, and I am far happier relying on the pump to get the mix right depending on revs and throttle, than I am relying on me mixing the right amount of oil every time I will with petrol and for that oil to mix thoroughly (and stay mixed) in the fuel.

If it had run out of 2 squeak oil then it probably would have seized. You get used to pulling the clutch quickly .

You would need a flywheel puller and in theory pullers to separate the crank cases. However the bigger problem is getting the cases back together over the crank. If you just use the bolts that hold the crank cases together to pull the cases onto each other over the crank you will land up with a massive side loading on the main bearings and they will fail rapidly. Main way the manual lists is to mount the crank in one crankcase half and then you use a puller to pull the crank into the other crankcase half.

The 122 doesn't have a massive amount of gearbox oil anyway. Half a litre isn't far from what it takes. Also likely to be fairly resistant to running a bit low on oil (just relies on splash lubrication anyway).

I would suggest having a good look to find the actual problem. Trashing the gearbox is unlikely to stop the engine from running unless you seized the gearbox (and you really would know about that). First thing to try is a compression check (spark plug out, compression tester gauge in, full throttle and crank the engine over until the gauge stops going up).

All the best

K
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[Djaniero]

Pm sent