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Right side exhaust too smokey


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mighty max
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Right side exhaust too smokey

Mon Aug 08, 2011 1:34 am » Post: #1 » Download Post

Good day lads, can anyone share technical advise or issue regarding my right hand side end can too smokey compared to the left side exhaust.. Could it be the crank that cause this? Question
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StephenRC45
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Mon Aug 08, 2011 11:45 am » Post: #2 » Download Post

If you're sure its smoking to much, even when warmed up it could be the right hand crank seal drawing in gear box oil.
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mighty max
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Mon Aug 08, 2011 12:38 pm » Post: #3 » Download Post

So you telling me that I have to changed to a new crank. I think it sip up the engine oil.
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Andy
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Mon Aug 08, 2011 12:49 pm » Post: #4 » Download Post

Not necessarily a new crank, but new seals.

The smoke will likely be quite white or grey if it's drawing in oil from the transmission.

You can actually replace the seals with the motor still in the frame if you want. It's a little tight, but easily done. You do have to split the cases and take the crank out to do it though.

Check the main bearings by hand to see if any of them "feel" rough or notchy. If you can feel any resistance or play at all, then that particular bearing is shot. Make sure you replace all 3 seals (R5K, MC21, MC28 have a rubber O-ring seal around the centre bearing).

If you are lucky, and it's just a seal, then it's not expensive at all. A couple of base gaskets, a couple of piston circlips, a clutch cover gasket, and the seals; although it probably wouldn't hurt to at least put a new set of piston rings in too, while you've got it all apart.
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mighty max
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Tue Aug 09, 2011 1:50 am » Post: #5 » Download Post

Thanks for the information. I did changed both piston and now this things happen. Now bike when back to the BIKESHOP again. Hopefully it's the seal...Currently the bike is standard outlook.
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Tue Aug 09, 2011 2:08 am » Post: #6 » Download Post

That's just "life", I'm afraid! Look at it this way though, those crank seals are probably the original ones, and depending on what model you have, could be anything from 15 to 24 years old!

Even if you have a 1996 MC28, you still have to expect things to be starting to wear out now. Even if it's low mileage, things like seals naturally deteriorate over time. That's the price of owning an old bike, soon to be classed as a classic!
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anonymous.shyster
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Tue Aug 09, 2011 3:57 am » Post: #7 » Download Post

The crank has to be pressed apart to change the centre seal, correct?
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mixalisen
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Tue Aug 09, 2011 5:41 am » Post: #8 » Download Post

Andy I think was talking about the o-ring that goes perimetrical to the main bearing (91301-KV3-771)...

Although if the problem is the main bearing oil seal that is placed in the inside of the bearing then yes you must split the crank in order to be changed...
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mighty max
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Tue Aug 09, 2011 12:08 pm » Post: #9 » Download Post

So far bike came back from service. Yup, you were right Andy, it's the seal. Minor job and now I'm not worry much when I'm on the road.
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