What will running lean cause over time?

[Detman101]

I ask this because my bike is currently running REALLY lean and would like to know the long term damage this is causing.
You all know my recent f-up with chopping off my mufflers...yada yada yada.
I'm trying to rectify the problem but more problems keep piling up and I would like to know if I need to just save up for a new engine.

Thank you,
Dm of mD

[Anonymous]

Personally I'm an ignoramus, but I've heard vicious rumors about air leaks causing hot spots and burning piston heads.

Michael

[lhanscom]

If you run lean you WILL destroy your engine. It will burn a hole in the pistons and lose compression, or maybe a valve instead. It won't take very long either. FIX THE PROBLEM!!! Don't kill a perfectly good engine.

[Detman101]

I wonder if it is already too late. Once the bike heats up to operating temp it first starts backfiring...then loses power and shuts down cylinder by cylinder. If I let it sit 10 minutes it will start up again.
Let it sit overnight...runs good again.

Dm of mD

[spots25]

yeah, it caus excessive heat and burns holes in pistons 8O

[KW]

I wouldn't run it again without putting some bigger main jets in it at least! They're only a couple of quid. Ooops, sorry, bucks!

[Detman101]

Okay, i'm putting my Dynojet 130 mains back in the bike and returning it to dynojet specifications. Rich is better than stock. I'll just have to eat the gas cost till I get it adjusted right.

I really don't wanna ruin this engine.

[Detman101]

Would it destroy the sparkplugs or cause them to fail as well?

Dm of mD

[lhanscom]

Yes, it can burn the electrodes up.

[Anonymous]

A lean Mixture will cause excessive cylinder head operation temperatures. The most probable effect initially will be scorn or cracked vlaves.

Averyone has good valid advice here so far.... Go back to stock.

[Jethro]

I can tell you from experience what happend to my bike. I melted the exhaust side cam right by #4 Cyl. Had to get a whole new head cause it melted the cam seat.

Lean = HOT!!!

[Detman101]

crap, that would suck.


Dm of mD

[bwringer]

Yes, lean = hot and hot = $$$. Make that $$$$$.

I am here to testify personally to that. Bad intake boot o-rings caused two exhaust valves to burn big trenches in themselves in my GS850G.

This touched off a sordid and expensive two year long epic adventure involving a vanishing cylinder head, a vanishing mechanic, and finally a vanishing bike shop.

Salvation finally arrived in the unlikely form of Nick Diaz, who happened to have an extra GS850 cylinder head.

Don't touch it until you sort out the jetting.

[Detman101]

BWRinger, what sounds or how did the bike act when it messed up?
I just want to find out so I know whether or not to tell the mechanic to check the valves when I drop it off at the shop in 2 weeks.

Thank you,
Dm of mD

[Anonymous]

Detman, I wonder if that's what's going on with my bike too. I chopped the mufflers off and put straight pipes on. When I was riding to work it shut down cylinder by cylinder and then started back up again after a few minutes. What do I need to do to fix it?