Spark plug / oil mixture / jetting

[bezoar]

OK, so I get the fact that if you mix your oil/gas leaner, the gas/air becomes richer. I also get the fact that jetting is key with regards to plug fouling. My question is what happens to all the oil other than make spooge? Doesn't some of that get on the plug?

The reason I ask is that I am in the process of jetting and my plugs are black. It is running well, although I am only putting around behind a beginner. I rarely am above 1/2 throttle.

I have a 2004 200, stock except boyesen reeds and snorkel removed. 155/42 stock needle 2nd from top, Br8es plug gapped, clean stock filter, sea level 90 degrees high humidity.

I have been mixing 32:1 Maxima formula K2, but plan on trying Amsoil dominator at 50:1 next tank.

The only thing I haven't done is check the float height due to lack of tool to measure that.

Any thoughts appreciated!

[OLHILLBILLY]

Sounds like you may be still a little rich on your pilot circuit. Does it foul plugs? I know it can't, because mine is still jetted stock with a 48 pilot and doesn't foul plugs, or spooge, with Klotz R50 mixed at 32:1, but I'll ask anyway.
If the bike runs fine and doesn't foul plugs, I'd say stay with the 32:1 mix and ride it.
But then, I don't buy into the 50:1 miracle oil theory. IMO your sacrificing your bottom end to maybe save a sparkplug once in a while.

[Julien D]

I agree with hillbilly there. I mix 32:1. Kawasaki recommends it, and there's nothing to damage from having a little too much oil other than the occasional fouled plug. If you're fouling plugs or getting excess spooge at 32:1, the solution is to correct the jetting, not change the mix.

[bezoar]

Appreciate your thoughts and I tend to agree. I am still wondering what happens to the extra oil when you mix 32:1 v 50:1. There is more to lubricate passing through, but does more get burned on the plug and more turn into spoonge? It would seem to make sense to use the least amount of oil to provide adequate lubrication.

As an aside, my plugs are black but seems to be running OK - no fouled plugs.

[Indawoods]

I am of the opinion that 32:1 is overkill due to the hightech oils we use today. 40:1 is more than adequate for any 2 stroke... and I would venture to say that 50:1 in a KDX is adequate because they are not running full bore all the time like MX bikes.

Spoo is a byproduct of the crap we get for fuel today and not a symptom of the amount of oil we use in our premix. Although proper jetting tends to help with spoo output.

Try race fuel sometime and see how much spoo you get.

[bezoar]

I still can't seem to understand ( maybe I am just too dense ) where the oil goes. More specifically, why do you not see spooge in a 4 stroke using the same gas with the same additives. My four strokes never foul plugs, the plugs always look great, there is no spooge. It seems to make sense that the fouling and spooge is in a large part, if not totally, due to gas/oil mixture.

[Indawoods]

A four stroke does not scavange the fuel back into the system like a two stroke does. It pops and leaves...

A two strokes lower end is also lubricated by the oil in your gas unlike a four stroke which has separate engine oil. So the oil/gas mix is all throughout your two stroke being used for everything. You cannot have the oil without the gas settling in the nooks and crannies of your motor. The crap that is in the fuel that does not burn turns to spoo....

[TWMOODY]

I seemed to notice less or no spoo when mixing 93 with tolune....
at 40:1

[Rick]

Yep. 40:1 Intercepter w/ 93 octane and proper jetting=minimal spooge. Adding race gas reduces spooge, due to more burn. Plus, the more you putt, the more you spooge...

[firffighter]

With the KDX there are a few issues that will cause the abundance of spooge.

1) Make sure you KIPS is clean.

2) Make sure you silencer is clean. Fresh packing or running the stock for a while without the plug

3) Correct jetting. I have always ended up jetting slightly leaner than what most here run and have had good results

That said, like others have mentioned, running the KDX between 40:1 - 50:1 is perfectly fine. I ran my 220 last year at 50:1 and when I check the piston and rings for wear at the end of the season, it was in perfect condition.

[bezoar]

Thanks for all yer thoughts. From what I can understand, spooge IS premix oil. It has to go somewhere, and that somewhere is out the exhaust. Since it is incompletely burned, part is gasseous (smoke), the rest is residue (spooge). There is some happy medium where premix/jetting result in more complete combustion and minimal spooge. I cant help but believe with proper jetting, less oil in the premix will result in less oil having to pass through the exhaust.

By the way, this forum is awesome!

[canyncarvr]

Re: '..spooge IS premix oil..'

Nope.


Re: 'Spoo is a byproduct of the crap we get for fuel today and not a symptom of the amount of oil we use in our premix.'

Yep.


..to a reasonable extent. If you happened to be jetted for running a 1:1 ratio and could fire it, I suppose there would be a noticeable amount of spoo that would be a symptom of the amount of oil used in the premix.

Everything that is in the fuel passes through the exhaust with the exception of the BTUs left behind.

To some extent the appearance of your plug is due to heat....specifically, the lack OF heat. The color of a plug is NOT an indicator of A/F mixture and jetting to a 'color' of a plug is a waste of time. You might as well jet to the current exchange rate of $$ to yen.

Re: '..in the process of jetting..'

...is something that involves throttle chop plug reads (not having anything to do with color), and engine response evaluation by your backside.

There is no 'process of jetting' that involves '..putting around behind a beginner.'

Certainly float height is a consideration.

IF what you're after is a picture perfect looking plug:


....given the description of the riding you're currently doing I wouldn't expect that to happen.

[shanana]

With the KDX there are a few issues that will cause the abundance of spooge.

1) Make sure you KIPS is clean.

2) Make sure you silencer is clean. Fresh packing or running the stock for a while without the plug

3) Correct jetting. I have always ended up jetting slightly leaner than what most here run and have had good results

That said, like others have mentioned, running the KDX between 40:1 - 50:1 is perfectly fine. I ran my 220 last year at 50:1 and when I check the piston and rings for wear at the end of the season, it was in perfect condition.

I agree with these sentiments. Oil technology have come a far way and looking into manufacturer specification on oil use, they tend to base their ratios on stock mineral oils and not high tech synthetic oils.

I used to mix my KDX 200 '06 at a ratio of 40:1 using MOTUL 700 synthetic containing ESTER and after repacking my silencer the spooge factor almost disappeared. I recently moved on to using MOTUL 800 racetech, also containing ESTER, synthetic oil mixing at 50:1. The spooge factor is NUL.

For those wondering what is ESTER; following is a laymen's explanation;

"Esters are stable molecules, provide good solvency, and provide very good low temperature and high temperature performance in engine oils."

[bezoar]

Thanks again for everybody's thoughts. I rode for about and hour yesterday using Amsoil 45:1. Spoo was still there, but at least it was not dripping on the swing arm from the silencer joint like before. Too early to tell for sure, but early results on MY 200 are less oil = less spoo. I think we can all agree that additives cause spooge and oil is an additive!!!!

I think I have the pilot and needle set fairly well from a throttle response standpoint so I CAN putt behind a beginner without bogging and fouling plugs - so far. I have not done a throttle chop plug read because I was under the impression that this was primarily to judge the main jet. Since I am mostly riding on the pilot and needle, and it seems to open up pretty well, I have not bothered.

Thanks again .....great hearing all your thoughts and love reading this site!!

[TWMOODY]

I think I have the pilot and needle set fairly well from a throttle response standpoint so I CAN putt behind a beginner without bogging and fouling plugs - so far. I have not done a throttle chop plug read because I was under the impression that this was primarily to judge the main jet. Since I am mostly riding on the pilot and needle, and it seems to open up pretty well, I have not bothered.


Does your putting around consist of less that 1/4 throttle all the time ?:shock:
1/4 throttle is where the transition starts from pilot to main.
Changing your premix is only masking a problem that exists.
Taking the time to jet your bike properly is not only doing it right
but is very rewarding when you snap the throttle.....

[fuzzy]

Keep in mind that there is leftover spoo in your silencer too...Can repack. Never jet based off spoo though!

[TWMOODY]

Keep in mind that there is leftover spoo in your silencer too...Can repack. Never jet based off spoo though!

Right on

[canyncarvr]

Re: 'I have not done a throttle chop plug read because I was under the impression that this was primarily to judge the main jet..'

It is to judge the main jet if it's a WOT plug chop.

A plug can be read in the same way in any throttle range you want to use.

Re:

Never jet based off spoo though!

That doesn't mean sometimes, once in awhile, or maybe.

It means never.

[bezoar]

Have the stock silencer - so no repacking to be done. I did remove the bolt at the bottom to blow some out. That seemed to be pretty much a waste of time.

Throttle response is good from idle to wide open. Plugs are dark brown/black - I guess because of the type of riding I am currently doing that is just the way it will be. No real problem because I have not fouled a plug yet! :)

May go ahead and do a chop this weekend, I do suspect I am still a little rich on the main, specially with the temp up in the 90's now.

By the way, just got my xr 400 fork springs installed. Thanks everyone for your help on that. Went very easily. set the preload at 5mm and oil level at 115mm. Will give it a ride this sunday and see how it feels!

Thanks again for your response