Need some help/advice. I have an '89 LT80 with the following mods: DG pipe, airbox with six 1" holes drilled, and removed two rollers on front clutch (per LT80's advice). The quad runs pretty well, but I want to rejet it for: good performance and, more important, bulletproof reliability. My kids ride it in the desert and, a lot of the time, at top speed for several minutes at a time. I'm not a wrench, and definitely have zero jetting experience. Ride at 0-1000 feet most of the time.

Recommendations?

Thanks.

 

What's the plug look like?
I'd guess dropping to a 90 main jet would be fine.

 

If you added a pipe and modded the airbox without adjusting the jets, I'm surprised it'll even run.

If you can cover those holes on the airbox and it runs better, you need to jet up. I'm not familiar with the LT80 carb, but I assume you can adjust (richen) the needle clip position too, Jack?

Usually when you jet up, you need to adjust the fuel screw out for the pilot jet, richen the needle jet and change out the main.

 

No adjustment, except for the needle.
The DG pipe is very similiar in performance qualitys as the stock pipe. The kids like it cuz it's loud.[img]i/expressions/face-icon-small-smile.gif[/img]
He has done nothing to increase air flows (porting) so the his drilled holes that allow dirt in [img]i/expressions/face-icon-small-happy.gif[/img] is of no concern to the jetting IMO.
The LT80 is jetted fat stock.Thus why I recommended the 87.5 as a safe area.

BTW:: stock is 92.5~~ I increase rpm's 45% and run a 77.5 in my motors.[img]i/expressions/face-icon-small-shocked.gif[/img] [img]i/expressions/face-icon-small-happy.gif[/img]

 

A 92 does sound fat for a stock 80cc. 77.5 sounds crazy for a modded mini though! [img]i/expressions/face-icon-small-shocked.gif[/img] I'm running a 105 without port work. It won't even hardly run with a 100 or a 110! Falls on it's face at full throttle. That's how sensitive this thing is.

Different breed I recon.

 

Thanks, all.

LT80, you're right - just from a non-wrench looking at it, the DG pipe doesn't look that different than the stock pipe. Probably wasted my money.

I have a stocking over the air filter housing to keep the dirt out, but probably not the water

Thanks, everyone for the jetting advice. I'll go with LT80's 87.5 and see how she runs.

 

Keep your eye on the plug and you'll be fine.

 

we allready ran a 80 main jet with stock motor you should be good with a 87.5 and yes the dg doesnt do much at all for the motor except make it louder.92 is stock jet on our 98 lt .