Starting w/o Exhaust system on

I would nominate him for a Kawis award "Humanitarian Division" for his rescue effort and his shelter.

But, Sadly, is is a day late and a dollar short because many people here (myself included) have already tried to rescue this poor, abused bike:laugh:

flht1997 wrote:

ok i agree cool air will be pulled in. but what temp exactly is the temp of the air coming in the intake side? i know the exhaust side is closed and the stem will not receive any cool air blast, but i feel that the mixture, while it will be affected, will not be signicatly leaned to cause engine damage when run for a short time.

The problem occurs after the bike is shut off, not while it's running. The reason I said it would probably be ok to run it for a few seconds is the valves won't have time to get real hot before it is shut down.

I wouldn't try start it. I believe the oxygen rich air stream can act like a cutting torch and cut valves and piston crowns.

RomSpaceKnight wrote:

I wouldn't try start it. I believe the oxygen rich air stream can act like a cutting torch and cut valves and piston crowns.

What oxygen rich airstream?

I have seen exhaust valves on automotive engines cut, due to a leaking exhaust valve and escaping combustion.

And I have started and run automotive engines for a few seconds with no exhaust manifolds and no adverse effects. Never tried it on a motorcycle motor but I don't see where there would be any difference.

I have seen people run an engine without maifolds on, looks cool, but I think another few min to bolt up the header on a bike is worth it,
the way my luck goes I would roast a couple of valves

i tried it for a few seconds just to see what it would sound like when i changed to a header pipe. it is loud but nowhere near as loud as running a open pipe. just a loud popping noise. the pipe amplifies the noise. real cool flames though.

I tried it on a two stroke piston ported single when I was a kid, wouldn't start, just shot flames out the exhaust and intake :laugh: :laugh: