Selecting your flavor of two-stroke oil has long been a subject for heated "conversation" on the trail and at the local dealer. I've witnessed out right arguments over the virtues of boutique oil (one way to refer to the high end low volume oil manufactures) versus the OEM oil that the local dealer swears by. The dealer swears the OEM's make the best oil, period.

Well, hopefully you've learned enough from past oil articles on the site to realize that no OEM actually makes its own oil. They merely provide a specification of an oils blend produced by specialty lubricant manufacturers to follow. Some of the standards are pretty low, based on what we've found too.

To understand more, Snowmobile-Online.com spent some time on the phone and via email with Spectro Oil's Mike Baldwin and Ken Ciocci. Both are factory reps with the Brookfield, CT firm. We asked the questions and they supplied the answers. As you'll see, a simple question doesn't always have a simple answer. The oil industry is extremely complex and the manufacturers are working overtime to make the best possible products for today's engines that are leaps and bounds more advanced than the designs of just five years ago. Features like power valves, Variable Exhaust Systems (VES), electronic fuel injection, and DPM are just a few of the engine improvements.

Snowmobile-Online - We've all read and heard a lot of different opinions about snowmobile oils. What should the average rider do to prevent oil-related problems in their sled?

Spectro - Snowmobile lubrication is one of the easiest things to take care of these days; however, some of us who were around snowmobiling in the '60s and '70s remember that it didn't used to be this easy. In the old days, we used to carry fuel containers and measuring devices with us to make sure that our oil was pre-mixed at exactly the right ratio, and if we made the mistake of choosing the wrong oil or mixing fuel at the wrong ratio, we took the risk of fouling a sparkplug or seizing an engine on the trail and facing a long walk back to the trailer.

Fortunately, the vast majority of snowmobilers these days have the luxury of a snowmobile equipped with an auto-lube oil injection system that has become so refined that fouling sparkplugs and becoming stranded due to an oil-related problem is extremely rare. In fact, engine failures related to oil or lubricant problems are almost unheard of. These days it's as easy as pulling up to the gas pump, filling your sled with premium and giving a quick check to make sure the oil reservoir is full and you are on your way! But, wait a minute...there could be a problem if you don't follow a few easy steps. And, I have a few suggestions with regard to snowmobile oils that could save you some time and possible aggravation during your snowmobiling season.

It may sound very simple but whenever filling or topping up your oil reservoir, be extremely careful not to let snow or rain to enter the tank. The slightest amount of moisture in the oil reservoir could eventually lead to a blockage in the oil pickup or feed line. An eight gallon fill-up should require the addition of about 16 to 24 ounces of oil to your reservoir, depending on riding style and make/model of sled. If you are using more, you should have your dealer check and readjust your oil pump. Remember, adjusting throttle cables at the carburetor significantly changes the oil mixing ratio! Get accustomed to your sled's thirst for oil and if you notice a sudden reduction in consumption, less than 16 ounces after an eight gallon fill-up, take immediate action! A worthwhile precaution in this scenario is to empty half a quart of two-stroke oil into a friend's reservoir, add ten ounces of gasoline to the remaining 16 ounces of oil, shake and pour directly into your fuel tank. This will get you home on roughly an 80:1 mix. If your auto-lube system failed or became blocked with ice, this should save some major expenses and headaches! Do a second check for oil consumption on the way home. Check your oil pump arm movement and even if everything is fine, the extra oil won't cause any harm but it will save you from saying the words, "If only." Also, remember to tighten the fill cap! I've seen this happen before where the cap comes lose and is lost somewhere in the belly pan of the snowmobile and a major mess is sure to follow. Oil on the disc brake rotor is no joke!

Snowmobile-Online - A lot of dealers say to use only the manufacturer's brand of oil since you could run into manufacturers warranty problems if your engine fries for some unknown reason. What if I'm on the trail and can't find it or I just don't want to use the OEM oil? Will my warranty be voided?

Spectro - When choosing a two-stroke snowmobile injector oil, most owners are inclined to follow the advice of their dealer and their owner's manual. This is the best practice and will give the owner of a new sled peace of mind. But snowmobile owners should be aware of the fact that none of the snowmobile manufacturers warrantees are contingent on the use of the manufacturer's brand oil.

Snowmobile-Online - What rating should I look for on the label of aftermarket oil? Are they really the same as the O.E.M. oil? I know this is going to be a lengthy answer since oil ratings are plentiful and just as confusing. I've always been confused by the labels that claim an oil is the panacea product for anything that uses injector oil.

Spectro - Most of the manufacturers oils are produced by specialty lubricant manufacturers and these formulas are tested and approved by the manufacturer for use in their sleds. The oils are blended according to a formula that has been developed for two-stroke engines and this oil is usually given a rating from the American Petroleum Institute (API) of "TC", the Boating Industry Association (BIA) rating of "TC-W", or the National Marine Manufacturers Association (NMMA) rating of "TC-W II." All of these formulas were originally developed for outboard engines; however, motorcyclists found that their air cooled engines ran the best on the oldest API TC oils. These API TC formulas contained a higher level of bright stock 150, a high density petroleum base stock with a consistency similar to honey, that gave the best protection against piston seizure and bearing failure. To prevent carbon buildup in the piston ring grooves, these TC oils used metal based detergents that were very effective in motorcycle engines but caused some problems in outboard engines operated at long periods of time at one throttle setting. A whisker-like bridge could form across the sparkplug gap to permanently foul a cylinder under these conditions while the motorcyclist operating his engine at a constantly changing throttle setting never encountered this problem. When the BIA developed the TC-W rating, they excluded the use of these metal-based detergents in favor of organic detergents to eliminate this problem in outboard engines. These TC-W oils (two-cycle, water cooled) also contained lighter base oils without the bright stock 150. For engines operating in the 4,000 rpm to 5,000 rpm range, the absence of the bright stock 150 had no affect on piston and bearing life. However, off-road motorcyclists testing these new TC-W oils were disappointed with the bearing life of their engines operating at 10,000 - 11,000 rpm and quickly returned to using the TC oils.

If you don't want the full synthetic, the petroleum based Spectro Sno out performs all the OEM oils in head to head testing. click for larger image

The BIA evolved into the National Marine Manufacturers Association (NMMA) which works closely with the outboard manufacturers. The need for a clean two-stroke outboard oil was recognized when piston ring groove carbonization was seen as a primary cause for engine failure and a new formula designated TC-W II was developed. While this oil was significantly better for outboard use and was phosphate free, it still was not the optimum two-stroke oil for engines operating above 8,000 rpm. Recently, efforts to develop an even cleaner outboard oil have produced the latest NMMA TC-W3 and this oil, although containing no bright stock 150, has produced remarkable levels of lubricity and cleanliness in piston ring groove areas.

In Europe and the Far East, two-stroke motorcycles and scooters still comprise a significant percentage of overall two-wheeled traffic. Manufacturers of these engines have determined that they need still higher quality levels for two-stroke lubricants.

In Japan, manufacturers have developed a series of strenuous engine tests that can identify poor quality oils if they don't measure up in performance. They tested over 250 samples of two-stroke oils worldwide and used the survey results to establish these engine tests. This became the JASO classification system. (Japanese automobile standards organization).

The tests include a detergency test, lubricity test, initial torque test, exhaust smoke test and exhaust blocking test. These tests have a much closer connection to actual snowmobile engine applications compared to TC-W3 tests which are all conducted on raw-water cooled outboard engines. And for the first time ever, an oil can fail the test if it smokes too much!

The detergency test evaluates the oil's ability to maintain the cleanliness of critical engine parts, including exhaust power valves. This is very important on power valve equipped Rotax, Yamaha and Polaris engines. The lubricity test measures two things. First, the engine is run with a load for 50 minutes then the cooling system is disconnected for ten minutes and the resulting drop in horsepower is recorded. This cycle is repeated several times and each drop in power is compared and it must not vary more than a specified amount or be more than a specified amount. Then the engine is run with increasingly leaner oil ratios: 60:1, 100:1 then 150:1. If no seizure occurs and power is maintained within a specified percentage, the oil passes. The initial torque test measures the engine's startability when cold, an important consideration for 3-cylinder 800cc sleds.

The exhaust blocking and smoking tests are run by mixing the test oil at an over-rich 10:1 ratio and running it in a two-stroke portable generator. The exhaust is channeled into a chamber where a photo cell measures the light that can pass through the smoke. It sounds crude but it works! Finally, a real world test to measure exhaust smoke from two-stroke engines! The exhaust blocking test simply examines the pencil sized exhaust outlet for carbon blocking. At a 10:1 ratio, these tests are very hard to pass. The highest JASO rating is FC. Lower ratings are "FB" and "FA." An even higher "FD" rating could be seen in the future.

In Europe, European two-cycle engine manufacturers were simultaneously working on two-cycle oil tests to separate the cheap, poor quality oils from the top quality oils. They tested the JASO reference oils in European engines and
their top reference oils in Japanese engines. They found that European two-stroke high performance engines needed an oil with a better detergency and
higher temperature performance than the best JASO "FC" oils. In April, 1997, they published their ISO global standards for two-stroke oils with two quality level categories: ISO-L-EGB and ISO-L-EGC. The ISO-L-EGB aligns closely with JASO "FB" and the ISO-L-EGC aligns closely with JASO "FC" for minimum test standards. Then, they developed the "GD" detergency test to run hotter and longer (3 hours vs. 1 hour) than the JASO detergency test. Oils passing the new ISO quality level, ISO-L-EGD would be superior to any previous two-stroke oils available! Of course, it didn't take long for oil manufacturers to develop and test oil formulations that pass this new quality test, and most of them involve using synthetic base oils. Running these tests is a very expensive and time consuming effort but in the end, a bottle of oil with one of these JASO FC/ISO- L-EGD certified ratings means that the oil meets the highest quality tests set by the engine manufacturer in Japan and Europe.

Polaris has recognized the "all-in-one" advantages of TC-W3 two-stroke oil and recommends the use of TC-W3 oils in their watercraft and snowmobiles. Interestingly, their new synthetic "gold" oil is not TC-W3 approved, it is the new JASO FC/ISO-L-EGD approved oil! Ski-Doo, however, specifically prohibits the use of TC-W3 oils in their snowmobiles and Sea-Doo watercraft, they recommended ISO-L-EGD oils while Yamaha recommends JASO "FC."
All of this may seem confusing and will probably make the choice of snowmobile lubricants even more difficult. In short, TC-W3 oils have a 10% higher level of lubricity than TC-W II oils and are a better choice for snowmobiles than any previous outboard oils. However, specially formulated snowmobile oils that pass JASO FC/ISO-L-EGD and do not follow NMMA restrictions will provide much better protection for higher rpm applications (snowmobiles generally rev higher than 8,000 rpm) and still provide a superior lubricity and detergency than TC-W3 oils at the same cost with less smoke. So, use snowmobile oil in your snowmobile and outboard oil in your outboard engine.

Snowmobile-Online - What's all this real story regarding synthetic oils? Is the extra cost over the petroleum based oils worth it in the long run?

Spectro Syn-Sno full synthetic oils formulated for power valve engines, is the oil of choice my project sleds. The oil is virtually smokeless which is a huge plus. click for larger image

Spectro - Synthetic base oils used in two-stroke formulas reduce carbon buildup, smoke output and help lower the pour point (that's the temperature at which a fluid changes from a solid state to a flow able liquid) of the finished formula. Less carbon buildup on the piston top and sparkplug translates to less chance for stuck power valves and detonation, and detonation is known to be the #1 killer of snowmobile engines! The #2 killer of snowmobile engines is overly lean carburetion and the #1 cause of overly lean carburetion is usually clogged or iced pilot or main jets. When snowmobiles are stored during the summer, it is very common for the fuel remaining in the float bowls to oxidize and form corrosion or varnish on the main and pilot jets. If these jets are not cleaned or replaced in the fall, the engine will run lean off idle and at full throttle leading to an eventual burn down. I've noticed that these jets rarely have these problems in motocross bikes where oil is premixed with the gas since the oil and the anti-corrosion additives in the oil prevent these problems. Before storing my sled I always make a batch of gas/oil mix and run it in the sled to make sure that the carburetor internals are protected from corrosion. A mix ratio of 50:1 to 100:1 is all it takes.

If your sled smokes excessively while trail riding (you know who you are!) you might consider trying one of the synthetic snowmobile oils available instead of the petroleum OEM oils. These oils are going to cost more money but the benefits will be reduced carbon deposits and much less smoke. Your friends will be thanking you!

Synthetic and synthetic blend oils offer advantages over conventional mineral oil products. They are better in extremes of heat and cold. They provide better oxidation resistance and thermal stability. Their extra cost is offset by the benefits a properly formulated product provides to your motorcycle engine. Compared to mineral-based engine oils, as we've stated, the oxidation resistance is far superior, the friction in both the application and the fluid, itself, is less and the synthetic products have much better low-temperature properties. The film strength of synthetic products is also better as is the natural detergency of synthetic base fluids, in particular, the diesters. They cost more but in most cases can be cost effective if increases in fuel economy, engine longevity, extended drain intervals and decreased operating temperatures, particularly, are taken into account.

Benefits of synthetic blends and synthetic oils
can be summarized as follows:

BENEFITS GAINED AND REASONS FOR THE GAIN

• Extended drain intervals possible due to greater resistance to oxidation
  
• Increase in fuel economy due to the lower internal friction due to even molecular structure.
• Reduced wear in the engine due to greater film strength of the synthetic compared with mineral oils.
  
• Cooler running engine since less friction causes less heat. This relates to oil temperature and not water temperature, which is controlled.
• Better cold flow characteristics due to less internal friction and very low pour points
• Faster oil flow on start up due to low pour points/less internal friction
• Cleaner engine since PAO and diesters have a high natural detergency plus detergent/dispersant additive use.