gas/oil ratio question

[srt2fast4u]

Hey guys thanks for helping me with my pipe questions a few days back i now installed the rev pipe and switched to boyseen reeds from fmf torque ones.

I have not ridden the bike since the switch but i am thinking of going to 50:1 mix instead of 32:1 for smoke reasons. How much will this effect my jetting.

KDX 220

rb car 36mm
fmf gnarly rev and powercore silencer
boyseen reeds
airbox mod

152main
48pilot
The needle rb sends with car(drawing a blank i think its a cek)

am i going to have to change to compensate

 

[tommrth]

i think more oil =more power so less oil = les power + motor wears out faster no idea bout jetting but you would be changing it to suit reeds and pipe any how

 

[glad2ride]

Why not stay well lubricated at 32:1 and just change your jetting??

Learn how to jet, plus keep your engine well protected. There's no need to start guessing at ratios.

Start with the air screw and pilot, then work your way up. (slide, needle, main)

 

[jasonent0613]

my cr250 melted the ring from 45:1

 

[leonard1]

To answer your original question changing your oil/fuel ratio from 32:1 to 50:1 will richen up your air/fuel mix about 1%. This could justify dropping one jet size.

 

[Papakeith]

pick a ratio and jet properly for the desired results.

 

[ignition retard]

my cr250 melted the ring from 45:1

But your piston was still intact?

 

[crhines]

Fredette races the ISDE using Golden Spectro at 50:1 and has never had an engine failure (over 20+ years). If you use a high quality synthetic (like Motul, Amsoil Dominator, Motorex, etc.) 50:1 is fine unless you're racing. I think Motul even recommends like 60:1 for trail riding (Motul 800 2-T), and they have no incentive to recommend higher mix ratios. From my experience, a lower ratio (with a high quality oil) will only cause excess smoke and spooge.

 

[srt2fast4u]

I was thinking the same thing it would be nice to have a bike that smokes alittle less

 

[jasonent0613]

the piston on my bike had big burn marks and the ring was melted to the piston.

 

[Kaleel]

I wouldn't go 50:1. These bikes will smoke regardless. They're supposed to. I installed a RAD valve, switched to a leaner jet, and adjusted the carb needle clip which eliminated the black sludge problem. But we're stuck with the smoke. That's why the EPA hates us.

Mike

 

[firffighter]

I've owned 2 KDX's both a 200 and 220 and have done all the mods you have mentioned. My brother also has 2 of these bikes and our riding buddy has a 200. None of them ever have a spooge problem. We all 3 run redline at 50:1. My brother and I did our top ends this winter and everything looked great. Probably no need to do them, but we went ahead to be safe. I have run the KDX's for 4 years in both tight single track stuff and wide open.

 

[geoffro]

no smoke

Kaleel, the bikes are NOT meant to smoke,and we are not stuck with the smoke.If the mixture is wrong they will smoke!
Bike manufacturers will always suggest a strong oil mixture to safeguard their reputation(they dont worry about you fouling plugs)

 

[firffighter]

I agree with geoffro. Lots of spooge is unburned fuel and is a sign of a jetting problem.