Lots Of Smoke - Burning Smell!

[al_orange]

It's taken me months to get around to sorting my Beta Rev 3 and getting it on the road but I've finally managed it. I took it for a bit of a run today. I rode about 1.5 miles at 35-40mph (comfortable for top gear) then rode around some wasteland for about 20 mins then rode back the 1.5 mile to home.

As I pulled into the drive, I could smell some sort of burning and there was a lot of smoke coming out of the exhaust. When I shut it off, the smoke continued to rise for about ten mins. I ended up taking the end can off to have a look and there was nothing too alarming to see. I haven't taken the packing out though and it MAY be a tad loose as it's new but it was the first time I'd repacked an exhaust.

Other than that, the bike starts first/second kick every time and runs really nicely.

Any thoughts to the smoking/burning?? It was quite a shock and I'd be nervous to take it out again until I'm happy it's not going to go up in a ball of flames!!!

I run the fuel at 60:1.

Thanks

[dadof2]

Looks like your exhaust has had a lot of old oil and some unburnt petrol in it and in the packing. A good run out on the road has got the exhaust hot enough to set the old oil on fire. If you look in you might find your packing has been smouldering.

Cheers

[al_orange]

What would cause the "old oil/unburnt petrol"? I repacked the end can recently so I assume the build up has happened since I did so. Could the bike be too richly jetted (although it does seem to run fine) or too leanly mixed (too much premix)?

I thought the exhaust packing was some sort of fibreglass that wouldn't catch fire? Is it very dangerous to have this happen?

Thanks

[pindie]

Its the black goo that burns.

It will have done the pipe a lot of good and cleaned it up.

Now re pack and it will be sweet.

Might have a rich jetting issue for small throttle openings though but you can check the jet sizes easy enough and ask on here.

[naichuff]

Remember there is a middle box where the oil can collect before the tail box You probably blown all the crap out of it into the tail packing as the engine does not normally work that hard for as long So the burning may be in there not the tail packing

[ham2]

Remember there is a middle box where the oil can collect before the tail box You probably blown all the crap out of it into the tail packing as the engine does not normally work that hard for as long So the burning may be in there not the tail packing

X 2 Here,that makes sense.

[al_orange]

X 2 Here,that makes sense.

That does make sense because when I repacked the end can, I really cleaned it out. Wire brush, carb cleaner etc. it was gleaming. The middle box though was pretty gunky and I had a bit of a go but couldn't get much out of it.

Just to confirm - it's not dangerous to have this happen then?? I'll be making the same run every day (as long as it's not raining!) so I don't want to mess the bike up.

[pindie]

I dont think it will be a problem as long as you let things cool down with the engine running. Exhaust fumes don't have much oxygen in so the fumes would stifle any possible fire. Get home and chug about your drive or whatever for 10 mins and it will be fine.

I had exactly the same thing with my Rev 3 (and old Raga 300) when I first got them. Since owning either of them it has never happened again so it does clear. As long as you don't let it burst into flames it will be doing it some good. It is old crap build up burning off.

You will need fresh packing once it has stopped doing it though.

Edited July 12, 2012 by pindie