Jetting difficulties

[Dunn111987]

Hello,
I built a Hodaka from a B+ frame and engine with a super rat pipe/fmf silencer and a rat air cleaner and 22 mm mikuni carb. I have black spooge dripping from the pipe were it goes into the cylinder and quite a bit of smoke. Using stock jetting for the ace 100. Does this sound like a jetting issue? I am new to working on bikes and am not quite sure we're to start with the carb. I have 130 psi compression when cold and 140 when warm. Any input would be greatly appreciated. And I'm using bel ray mc1 at 20:1.

Thank you,
Ryan

[Hydraulic Jack]

Spooge is a normal state for a two stroke engine. No one runs completely clean, and oil residue itself is not a jetting thing. More a premix ratio thing. If you are running trails or back roads, and not racing flat out, 20:1 is more oil than needed and will cause excessive spooge. If it runs well, pulls clean, and does not foul plugs, clean the spooge once in a while and ride it.

If you want to reduce the residue and are willing to deal with jetting, try 32:1 or even 40:1 and see how it goes. Assuming it runs correctly now, leaning out the oil may require a bit of jetting tweak but not much.

[bchappy]

Bel Ray MC-1 is a VERY good oil but Hydraulic Jack is right on. 32:1 may stop the smoking.

[Dunn111987]

Ok! I will have to try it out. Says something about 50:1 to 80:1 on the bottle. Should I go with 32:1 or is 50:1 safe with a full synthetic oil like this? I'm new to tuning 2 strokes, so I appreciate this input! I ask a lot of questions. I'm eager to learn and I love the bike I built! Just want to make it correct before trail riding

[bchappy]

I run MC-1 at 40:1 in my Hodakas and haven't had any problem smoking or engine failure.

[Hydraulic Jack]

Synthetic base oil by itself isn't a reason to run oil lean mixture. We used to run bean oil at ratios between 30 and 40 to one. That said, synthetics generally do have a greater resistance to high heat than petroleum oil, and tend to hold film on pistons at high temps and high rpm, so they are a bit more tolerant of abuse by leaning. Bean oil also has high temp resistant properties. I would not go more lean than 40:1 synthetic or not unless you want to experiment. Really oil lean mixtures are more aimed at outboard engines. Find an oil intended for two stroke motorcycles, not outboard engines or string trimmers.

[bchappy]

I tried bean oil years ago and it fouled more plugs than I can count. I went to MC-1 and can't remember the last plug I fouled.
Just my $.02.

[Bill2001]

But mercy me, that unmistakable bouquet of Castor...

[Dunn111987]

I will try 40:1 and see how that works! Did you have to make changes to the jetting with that ratio? And what model of Hodaka did you use it in? Is it safe to try it out with the stock ace 100 jetting and then go from there?

[bchappy]

Running it currently in a model 97 Super Combat and a model 95 Combat Wombat and I started them off with MC-1 as soon as they were restored. They are both modified and I have different carbs than stock so I would not be able to answer your question about jet size. I would just start with what you have and if it runs clean maybe try to raise the needle one notch (lower the clip) and raise the main jet one size and see if that is to rich. I don't think you will need to do this but just to be safe.

[MTrat]

Back to the bean oil... I'm sure a lot of us old buggers get a quick adrenalin rush upon smelling a little whiff of that racy odor. Synthetics just don't make the grade in that department.

[Larry S]

Maxima Castor927. I've been running it in 4 Hodakas for 5 years with no oil related problems.

Larry S