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Oils you wouldn't recommend

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Please tell me what oil you think is no good and why.

(If an engine seized then a bad oil at a high fuel oil ratio could have contributed but most likely the main jet was too lean or there was an air leak)

Ring life is a good indicator.

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Also if you changed oils and the power was better and the engine lasted longer then I'm curious to know the details.

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On 8/30/2017 at 2:09 PM, jaguar57 said:

Please tell me what oil you think is no good and why.

(If an engine seized then a bad oil at a high fuel oil ratio could have contributed but most likely the main jet was too lean or there was an air leak)

Ring life is a good indicator.

I wrote this quite a few years ago so it's a bit outdated, but here it is, do what you wish with the info.

This isn’t exactly a scientifically conducted test, it’s just my opinions and observations about several different oils that I have tried over the last few years, on both my KX250 and my KDX250. All of these results are obtained running a 26:1 ratio, with jetting as close to perfect as I am capable of. Each oil was used through the life of at least one top-end. I only use Wiseco pistons and rings.

Golden Spectro: This oil did a good job of protecting the piston and cylinder. The piston was a little shiny on the intake side, but wear was within specs, and the piston and cylinder otherwise looked OK. There was a good coating of residual oil in both the top and bottom of the engine. It is a dirty-burning oil, however. It leaves a lot of carbon deposits on the piston crown and head, and really gums up the ring grooves and the power valves. And this oil spooges a bit too much. No matter how sharp you try to jet, the spooge simply can’t be completely eliminated. I wouldn’t run this oil again unless I had no alternative, it’s just too dirty. As a side note that may or may not be related to the oil, this is the only pre-mix that I have ever had an engine failure while using, with the thrust-bearings on the KDX250 crank pin seizing. It was probably just a fluke, and I can’t pin it down to lubrication failure, but it’s always stuck in my head.

Maxima Super-M: This oil didn’t protect the piston as well as I would like to see in my engines. The piston was noticably shiny and scuffed on both the intake and exhaust sides, and the top-end was almost dry upon tear-down, although the bottom-end seemed to be well lubed. The ring grooves were reasonably clean, but the piston crown and head had significant deposits, as well as the powervalves, although not as bad as the Golden Spectro. Another oil that I just can’t recommend, it just doesn’t seem to leave the engine well lubricated or clean. I also felt this oil left an off-color on the plugs, making jetting a little more difficult.

Maxima Castor 927: Very slight scuffing on the intake side of the piston, but over-all everything looked good. The ring grooves had slight deposits, and the piston crown and head had slight build-up that was well within reason. The powervalves were gummy, but not to the point of seizing or failing, again within reason for a non-synthetic oil, and excellent for a castor-based oil. Both the top and bottom-end of the engine were very oily and well-lubed with plenty of residual build-up. And the smell of this oil is wonderfully sweet, better than any other oil I’ve used. I liked using this oil just for the smell! Overall a good oil with no real bad points.

Redline: This was a strange oil. The piston and cylinder looked good, with minor shiny spots but no scuffing, and everything was reasonably clean and well-lubed. But this oil actually left surface rust on the crank wheels, and tarnished the carb brass. It also had a tendency to gum up the carb jets for some reason. How a metal surface can be both oily and have rust on it is beyond me, but clearly this oil lacks any proper corrosion-inhibitors, or it is so rich in esters that it absorbs huge amounts of moisture from the air. I would never use it again, nor could I recommend it.

Mobil 1 MX2T (Racing 2T): The piston and cylinder looked great with this oil. No noticable shiny spots or scuffing on the piston at all. The top and bottom of the engine were well lubed with plenty of residual build-up, and even the powervalves were oily and lubed. No other oil that I’ve used compares to the cleanliness of this oil. The piston, head, and powervalves were nearly spotless, the valves didn’t even really need cleaning. If I were a serious racer, this would be my oil of choice. The only reason I no longer use it is the awful, acrid-smelling exhaust it produces. Since I just play-ride with my buddies, they all complained srongly about the smell when they were riding behind me, and my brother-in-law went so far as to tell me he would ban me from riding with him if I didn’t change oils. (Edit: this oil is no longer available)

Bell Ray H1R: This oil was similar to the Super-M in every way. It left the piston shiney and scuffed-looking, although the top-end wasn't left as dry looking. Deposits were less than with the Super-M, but still heavy enough on the valves to be a problem for riders that run their top-ends for extended periods of time. I could see this oil gumming up the valves enough to cause them to stop functioning. An acceptable but un-exceptional oil.

Yamalube 2R: For a dino-based semi-synthetic oil, this is an exceptional product that performs as well as any full-synthetic out there. The piston and cylinder always look good, with no significant shiny spots or scuffing. The ring grooves, piston crown, and combustion chamber were very clean, with only a light circular carbon pattern on the crown and head. The valves are almost as clean as with MX2T, although not clean enough to not need removing and cleaning. The top and bottom of the engine are always well lubed with plenty of residual oil, even on the powervalves. This is my oil of choice, and I whole-heartedly recommend it to everyone, racer and casual rider alike.

These are only a few of the oils on the market. There are plenty of great oils out there for people to use, these are just the ones I have personally used.

Edited by The Spanky
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Great report. thanks. Can I put it on my web page about oils?

Too bad you didn't try Motul 800. I think it would of scored well in your test.

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I don't care what you do with it, I publicly posted it on a free website. But it's nothing more than anecdotal observations of mine, certainly nothing formal or scientific, it was just an off the cuff answer in an oil thread. Your mileage may vary.

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