125 Wombat gear oil?

[Dennis Bannert]

I have a pristine 1973 or 2004 125 Wombat. I had it serviced in 2006 then parked it in my dry shed. All cleaned up and juiced and slowly driving it around to check for issues. Came in the driveway, stopped & looked down to see oil running to ground. It was pooled on the top of the gearbox and running off but can't source the leak. Did I overfill with gear oil, did I use the wrong gear oil, is there pressure, do I have a crack? I'm using "MTL Fluid" 80 wt transmission lube for 2 & 3 cycle transmissions not the SEA 30 as specced in my owners hand book. Any suggestions would be helpful.

[hodakamax]

Hi Dennis, It sounds like an overfill, check the dipstick. I've not tried that oil before and it could be suspect. 30w non detergent oil is no longer available or at least hard to find. I personally use Mobil 1 Racing 4T 10W-40 synthetic which is rated for transmissions and wet clutches. The Gang will probably have some other choices. If any moisture has accumulated in the transmission-clutch area it does expand and create temporary pressure but should evaporate quickly. The oil is almost certainly coming from the vent on top of the crankcase.
Hope this helps!

Max

[Brian4236]

Hi, Dennis. Something similar happened to me last year (I have a '72 Wombat). I had checked the dipstick and thought the fluid was low. It was "low" because the bike was leaning on the kickstand when I checked it. Plus, I might have just overfilled it because I wasn't paying attention.
I use Bel-Ray gear oil now, but I have used Yamalube and Honda brands in the past. I'm no mechanic, so I generally just do what people recommend on this site. For example, about five years ago Rich Gagnon recommended Red Line Two-Stroke Racing Oil with premium fuel. I have used that since and have not had any problems.
--Brian

[hodakamax]

Dennis and gang. This is a subject that comes up regularly on the forum. I use Mobil 1 Racing 4T 10W-40 synthetic because it meets all of the specs for a wet clutch and transmission. Yamaha,Honda and many others have oils that meet these standards. I'm wondering why (and this is just a question) some choose to use 80W plus in this application. In the early days of Hodaka racing we used Automatic Transmission fluid because it was thinner and created less drag and was rated for wet clutches. It looks to me that 80W would create unnecessary drag. Of course synthetic oils of today are probably far superior to ones of those times. Any thoughts on that gang?

just curious--

Maxie

PS--Someone did mention in the past that the W rating has different values for gear vs engine oils. Is this the case? (more questions!)

[Zyx]

85wt transmission lube, like BelRay and Maxima, are actuall fairly light viscosity oils, not to be confused with 85wt diff lube or hypoid oil, which is quite stiff. I would put 85wt motorcycle transmission fluid, rated for wet clutches, at around 20wt if it were a motor oil.

[hodakamax]

Actually I have too many vehicles. I like the Mobile 1 4T 10W-40 because it works well in the farm Yamaha 4-wheeler, a Yamaha XS-650, KLR-650, a Yamaha RZ-350 set up for road racing and all Hodakas which all have gear contact. Some run it through it through the engine. It meets all the requirements for engines, wet clutches and transmissions with no reservations in all seasons. What a product! (as all the Yamaha, Honda, etc. oils with that rating do.) Oils have improved it seems.

Maxie

[MTRob]

Dennis, Brian says he uses Redline in the gas mix. So do I, I really like Redline even use it in my truck. I also use Redlines motorcycle 80 W gear lube
with shockproof, its an all synthetic formula. Seams to work just fine no problems. Try that, I have to order mine from Amazon our dealer went out of business. Everybody has there favorite.
MTRob

[socalhodaka]

I like the Spanish brand.

[hodakamax]

Well Kelly, you did make me giggle!---The atmosphere is improving already.

Maxie

PS--I think I'm off for Italian food tonight and a redline, er--red beverage--Good idea!

[socalhodaka]

Right, I have ran just about anything I have had left on the shelf. It's a Hodaka, even in my race bike I have run ATF, straight 30wt and what else. Now the I have recycled all the left over I run the Belray 80wt with no issues. We'll I have had no issues with any of them, so just run what is easy to get like the Bel Ray. Now that your sure about the crank oil, don't run the 20:1 mix that is says on the tank sticker or you won't be happy.

[fullchoke]

in reference to the 20:1 on the filler cap.....why did Hodaka put that there if their engines won't run well at that ratio? I've always been a 4 stroke guy until my son and I got these Hodakas and I've always run 20 or 25:1 in my chainsaws and weed eaters and blowers and I've never worn one out and they run perfectly. I put the same mix in our Hodakas and like a 4 stroke guy, forgot to take a spare plug when we went to HD14. Is it the racers that won't be happy because they can detect a power loss. I'm not a racer so my little Hodaka 125 goes plenty fast for me.

Thanks

[taber hodaka]

In the earlier days 2 cycle oil was usually for boats that were actually water cooled. If you run the chainsaw professionally you tuned it or adjusted it. Running a engine too rich you loose allot of power. In the 50's some machines were 16-1. Quality oils allow the engine to run much cooler therefor can be leaned out and get much better mileage. A hodaka fouling a lot of plugs is too rich needs leaned out or a hotter plugs. With the quality of 2cycle oil today use the good oil mix at the recommended ratio or the ratio others are using and tune it. In the early days we used 30 wt car oil. My 1952 Harley was a 2cycle. Anyone that raced a lot of years won many trophies without engine failure and tuned their own machines are good tuners It is a learn by doing thing or a mentor. Many hodaka shop manuals cover tuning very well. A tuned 125 will run better ,tuned to what ever gas oil or mix ratio you use .Amsoil mixes at 100-1 . Each of us see things differently and some use better words explaining it in a more understandable manner.-------------Clarence

[fullchoke]

Thanks Clarence for the explanation. I'll try to explain how I see it. I understand some of what your saying but the lean or rich condition seems like it would depend more on your air/fuel ratio more than your gas/oil mix ratio and it doesn't seem like a few ounces of gas in your tank as opposed to oil would make too much difference in power or economy. When people talk rich or lean aren't they talking about the air/fuel ratio? What I don't understand is if the engine was designed for 20:1 oil mix and you mix a higher quality oil at the recommended ratio, you should obtain better lubrication, the engine should run better. The higher quality oil should also burn better and leave less deposits too. We haven't run our Hodakas at high elevations, so I don't know if we would find a rich problem there(air/fuel), but they ran fine at low elevation and the Bad Rock last year. 100:1 ratio scares me, even if AMS Oil says its good. I don't know why anyone would find it advantageous to run that. I want to avoid top end rebuilds, I can live with some extra smoke. I will bring a couple extra plugs when we ride next, but so far we haven't needed them.
I used to collect old chainsaws and those old 2 man saws ran at 16 to one and I have seen 12:1 gas/oil recommendations, but there were no speciality 2 cycle oils back in the 40's. I don't tune my modern chainsaws I just run them at 20:1. I don't ever remember fouling a plug and I cut a lot of firewood, since that is how I heat my house and my little christmas tree farm, keeps my saws busy too.
The little super combat was bought used so I don't know about prior rebuilds if any, but it surprises me sometimes how quick it can be. It isn't fast or powerful like my Honda xr650r is on fire roads or my vmax for that matter, but it is fast enough on trails for an old man like me. I'm going to keep running 20:1 until I learn of a problem in doing that.

GM

[Zyx]

http://www.klemmvintage.com/oils.htm

Full discussion on premix oils, piston seizures, etc. notice that some folks still use 20:1, even with high quality oils.

[Zyx]

Maybe one of the guys who worked at Pabatco could say whether the Hodaka was "designed" for 20:1, or if that was just the default position of 2stroke engine makers of the day. Personally, I don't think you can design a two stoke to use a particular mix of oil.

[bchappy]

My thought on the subject is that "back in the day" with the quality of available oils it took 20:1 to properly lubricate. Oils have improved so much it does not take that much oil to do the job. 40 and 50:1 is not unusual. However, I was running Bel-Ray MC1 synthetic in 1970 at 30:1 with good lubrication and very little plug fouling. I am now running Bel-Ray MC1 at 40:1.

[hodakamax]

I agree Bill, I suspect that in the day outboard motor oil and automotive engine oil probably came from the same faucet. Designer synthetic oils lub so much better and at higher temperatures that less is needed. I'm still amazed at the air cooled chain saw of today. At 40-50 to 1, it works all day in extreme conditions under big loads at high RPMs without complaining. I'm in the middle with Yamalube 2R at 32:1 for the Hodaka.

Maxie

[fullchoke]

What I meant by designed was more like engineered to run at 20:1 because of all the oils available back then, adequate or proper lubrication could be received with 20:1 and if you did use a higher quality oil at 20:1 all the better. That is my opinion today... if the lesser or lower quality oil ran good at 20:1(it should have because it was recommended) then todays synthetics which burn much better and provide better lubrication... why not run them at 20:1 too? Unless you think there is over lubrication and can put up with more wear then lower the ratio to 40 or 50:1. Possibly racing motivates tuners to extract a little more power out of a lower ratio and they rebuild their top end regularly as they would expect. I don't race and if I did it wouldn't be anything serious, so I want all the lubrication I can get so I don't rebuild hardly ever. I think the more lubrication, the better, but I limit it to 20:1 because I know the new oils work better at both burning and lube. I would be interested in comparing the burn quality of 1970 oils to a good synthetic made today. We may find that running modern oil at 20:1 is comparable to 1970 oil at 40:1 in burn residue, without the wear.

I would guess that plug fouling at any gas/oil ratio has more to do with a dirty air cleaner causing a rich air/fuel mixture than the gas/oil ratio.

gm

[Zyx]

The Super Combat owners manual specifies 16:1 fuel mix.

[hodakamax]

I would think that the main advantage of synthetic two-stroke oil today would be that it has a much higher temperature limit before it loses its lubricating properties. We discussed this a while back on the subject of piston seizure both on the Forum and the last issue of the Resonator. Whatever ratios we desire must be jetted for because a large percentage of cooling in an air-cooled engine is from fuel atomization and evaporative cooling. Too much oil displaces fuel and can influence fuel leanness.

Anyway, as I always say--Whatever works, but you will get more performance with less oil. I think if you are happy with your combination (they all seem to work). It certainly doesn't hurt to have too much lubrication (up to a point as you say) if you jet for it, although good rated two-stroke oils are also somewhat combustible.(non cooling but add power) Complicated huh? This is why Max has only moved up to 32:1 in 50 years! (and I always run borderline rich--more cooling AND more lubricant.)

As always,

Maxie

[fullchoke]

When your too lean and the piston seizes it is your fuel to air that is too lean and this condition can't be solved by more oil in the fuel. The oil ratio controls wear but not seizures. That is how I have always looked at it in general. In a 4 stroke you don't have a seized piston when fuel to air gets lean you get a hole in the top of the piston. The lean condition produced excessive heat.Too much oil influencing fuel leanness shouldn't be allowed to happen. Jetting would be way off in a trail riding machine. The racing engine runs closer to the edge, and it has to account for the lack of cooling when the throttle is closed at a high RPM. If I want more performance I twist the throttle. I know what you mean, but I'm not tuning for a competitive edge. I'm looking for rideability and longevity and I seldom run wide open on the main jet for very long anyway.

I wonder what was behind the 16:1 ratio for the Super Combat? That seems overly cautious for a racing machine, which is what it was in 1974. Did Hodakas have a new bike warranty? and it became void if not run 16:1?

This all started because someone stated that you don't want to run 20:1. Funny thing is I do want to. Maybe the reason right now has to do with a Super Rat cylinder needing a piston and a torn down CR500r needing a re-slieve and I didn't run either of them into that condition.

Now back to 125 wombat gear oil.

GM

[hodakamax]

Hmm---We did get a little off course.

Maxie

[Bullfrog]

20:1 ratio was molded into the gas caps due to the following things (and perhaps others):

- state of the art of pre-mix fuel in the late 50's and early 60's
- conservative engineering recommendations (too much oil is "safer" than too little oil)
- "inertia" -- once an engineering decision is made (and has served well for years) it takes some hefty reasons to change it.

Note: We ran 40:1 in the ISDT Qualifier events in the 1970's. Though I usually run 32:1 these days.

Ed

[Zyx]

Thanks Ed. Figured you would know.

[Bullfrog]

Hmmm, come to think of it (and getting back to the original question) -- 30WT non-detergent motor oil was the "hot" set-up "wayeee back when" too! It provided relatively low viscosity (to keep from using up your vast reserves of power just spinning the gears in an oil bath), non-foaming characteristics, and was readily available. In fact, you could probably have used the same can of oil to top off the family Nash Rambler, your Hodie transmission AND have some left over to mix up some Hodie fuel! Ah, the good ol' days (?).

Ed