can an engine get damaged from running lean?

i know the carb is set up almost spot on and the engine runs great, but i have a very small exhaust leak where the header connects to the pipe. i think this leak is making the engine run lean, but will it cause engine damage as opposed if the carb was set up lean?? ive done a 100 different things to try and patch it up but some how it still finds a way to leak.

very unlikely. If you were lean on the MJ and did lot of WOT riding it would be a different story.

I agree...I don't think that's a problem to worry about.

But a very lean engine can be damaged. LEAN=HEAT Of course, heat is the enemy.

ok right on. ya i went one size bigger with my new pipe so thats alright. and the leak is barely noticable at all so i was hopen its nothin to worry about.

On a thumper i don't see how anything can get hurt internaly since lubrication is not part of the intake, it would ping probably a little, but nothing serious should happen.

On a thumper i don't see how anything can get hurt internaly since lubrication is not part of the intake

lean MJ = hot piston = melt or nip :thumbsup:

It wont do any damage to the bottom end if thats what you are refering to

you're kinda right.

lean jetting will cause a motor to ping espcially in the winter.

you've gotta be very lean to melt the motor, it has happened though.

I assume that this is a four stroke runnin lean. If so, you'd normally get lots of decelleration popping. Sounds like your exhaust leak is changing that behaviour. If it were causing a lot of decel popping I expect you'd richen it up so why not richen it up anyway.

has anyone found a decent way way of sealing up the pipe joint yet ive tried alsorts of sealers and they all seem to get blown out

Welding it back is the only way. The pressure, and the heat will blow all sealers off of pipe. Belive me, I tried.

You may want to replace it. I found a header pipe on E-bay for 25.00 to replace my cracked one. Good luck :thumbsup:

ya think stock is a 175.i think ive got a 180 or 82 in it. theres almost no popping at all on decel. but the plug is always white anyway.

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