Motorcycle Oil Questions. Spectro Answers.

Oil is to engines and transmissions what blood is to humans. Hmmm. Kind of… Oil serves many purposes like lubrication, cooling, efficiency, anti-rust agent, protection etc. These are the 3 most common questions about motorcycle oil. Spectro Performance Oils explain:

1- Question: Can I mix viscosity grades? Answer: Yes, you can and no harm will be done. Topping up with 10w40, if its all you have available, will not injure the 20w50 in your crankcase. It will, however, lower the overall viscosity of your crankcase oil to a certain extent. This will cause no harm to your motorcycle. Likewise, adding a 20w50 product to 10w40 will slightly increase the overall viscosity in your crankcase. Again, no harm will occur.

2-Question: Should I use a straight weight or multi-viscosity product? Answer: Multi-viscosity products are the preferred product in modern engines. They offer better flow upon initial startup and are more heat stable than straight weights. In the vast majority of motorcycles and particularly 1970 models forward, multi-viscosity is the preferred product. Older and antique models may require straight weights of SAE 40, 50 or even 60 in some early Harley-Davidson models. Your owners manual should be a useful guide in viscosity selection.

3- Question: I had read that high levels of phosphorous and zinc in motorcycle oil is harmful to catalytic converters in motorcycles. On your website, it states that your motorcycle oils have high levels of these minerals for specific motorcycle needs. Would your oil have an adverse effect on motorcycles with catalytic converters? Answer: No, there will be no adverse affect on your catalyst. The motor oils for the first 20 years of catalyst use in America were designed with these levels of ZDDP without any problems. However, vehicles with unusual oil consumption problems and very poor maintenance history could encounter catalyst clogging around 100,000 miles. The laws were passed to restrict the levels of ZDDP in oils for the benefit of these vehicles which do NOT include motorcycles.

14 Responses to “Motorcycle Oil Questions. Spectro Answers.”

  1. 1 Robert Drew Aug 26th, 2010 at 8:03 am

    Still confused why an oil brand is better than another one. Please, explain.

  2. 2 jesse Aug 26th, 2010 at 11:35 am

    Would also be interesting to hear their take on the the classic question of “Can an automotive oil be used safely in a motorcycle? Why or why not?”

  3. 3 Bigal Aug 26th, 2010 at 11:47 am

    What about the Amsoil, I thought that was the Best. I saw where it looked really clean after 6,500 miles on an HD Duece in Daytona? A Crew of Dood’d were praising the Oil in combination with a K&N Oil Filter. I know that you want to chjnge Oil 2500-3000 miles, but these Guy’s wre telling me ‘that if you use this, you don’t have to and Why do you want to change at 3,000 miles if it isn’t necessary. Also what’s up with this Royal Purple Oil?

  4. 4 Rollin Aug 26th, 2010 at 2:11 pm

    Rollin here from Spectro, I’ll do my best to answer the questions so far:

    Robert: Just like any product, it comes down to quality of raw materials and skill / ability of the manufacturer to make something out of them. We start with the best raw ingredients money can buy and carefully “batch blend” them into a super premium oil, we’ve been doing that since 1966. Another critical step is additive levels. All Spectro motor oils contain 1800ppm zinc and phosphorus, which are primary anti wear ingredients often reduced in other brands. To my knowledge we have the highest zinc and phosphorus levels of any motorcycle oil.

    Jesse: Automotive oils (even Diesel) now contain between 600 and 700 ppm zinc and phosphorus. I would not recommend them in motorcycle applications.

    Bigal: Many manufacturers use “tests” to show their product is the best. They spend in some cases hundreds of thousands of dollars to test every possible SAE and API test, and then publish only the results that show their product as superior. Many of these tests aren’t even for motor or gear oils (many times industrial applications such as air compressors or pumps), but they fail to tell you that in the “results”. Sadly, many consumers just look at a bar graph and think “it’s higher so it must be better”. Changing oil is a good idea, you can’t do harm by over changing. We recommend 2,000 miles for mineral oil, 4,000 for Synthetic blend and 6,000 for full Synthetic, or before the bike is stored for long periods (winter). Oils that are colored (Royal Purple, Redline and others) just contain a color dye (we dye some gear oils red or green) The color has no effect on oil performance, it just makes it look different.

  5. 5 Little Joe Aug 26th, 2010 at 3:44 pm

    Nice info, thanks.

  6. 6 Brian Aug 26th, 2010 at 4:06 pm

    Rollin, thanks. But that still isn’t good enough. I’ve used Automotive 15/50 Mobil 1 in my engine on this bike for 77,500 miles with no adverse affects. No abnormal wear, no oil consumption and the cam chain shoes also looked great after 35K miles. My buddy changed his cam shoes at 52, 000 miles and the mechanic stated “your shoes are only slightly worn with the rest of the cam parts looking brand new. So we both attrubute this minimal wear to regular oil changes at 2500-3000 miles max and fully synthetic oil. Not necessarily the brand. I ride differently than him. I’m not afraid of 5kRPMs. he stays away from it. It seems oil like most things engine related, are a matter of passion, trust and life experience. So my question is pretty simple. Why is your oil so much better in making an engine last longer for twice the cost per quart? I just compared prices. Spectro $14/quart. Mobil 1 $6.49/quart for automotive or $10 for motorcycle specific Mobil 1.
    Isn’t the real results based on choosing the correct viscosity for the application, use and interval of oil change. More so than the brand? Any of the current selection of full synthetic oils is a great product by comparison to oils we had in the early 70s or before.
    In my experience (40 years of rebuilding or building motorcycle and auto engines, I’ve only seen 3 cases of oil related problems causing damage. Two were the owners fault due to low oil level or extended interval of changes. The other was due to bad hard facing on the camshafts (Honda V65). None of these instances could be traced directly to the fault of the oil. I believe in making the best educated guess, but it still comes down to personal choice and a bankroll. With most HD owners putting maybe 10-20k on their bikes in the time they own them, oil will not be the problem they run into. Newer models and ready cash will be the culprit.
    I realize you are a businessman providing a quality product and for that and all the other vendors that support motorcycles, A Big Round Of Applause. Just help us sort fact from emotion.

  7. 7 Woody Aug 26th, 2010 at 4:49 pm

    There never will be one, best oil. Some motorcycles share their engine oil with the tranny so it’s also on the clutch plates & gears. Friction fighters that may be great in one bike area glazed clutch in another. Likewise air vs liquid cooling and things like cylinder HP (crank load) and how heavy your cam springs are.

  8. 8 Rollin Aug 26th, 2010 at 5:04 pm


    Prior to about 2 years ago, many automotive oils contained generous amounts of zinc and phosphorus. All mainstream automotive oils today (including M1, Rotela diesel and Delo) are limited to 600-700 ppm. They also lacked the shear stability and addative packages that motorcycle oils have. Whether you use my brand or not, I would personally not use automotive oil in motorcycle applications. On the price question, our oils (and other quality MC oils) are expensive to produce due to the quality of raw materials and additives. You do get what you pay for, I’ve had many HD and Metric riders approach me at shows saying ” I’ve used your product since new and have over 100k miles without any problems” Maybe they were just lucky, but a quality oil does make motors last longer.

  9. 9 Rogue Aug 27th, 2010 at 7:31 am

    I have been using Spectro oils since 2005 and have 97849 miles on my 2004 FLHT.
    When I bought my 2009 FLHT I switched to Spectro 20/50 Golden as well as changed primary and transmission to Spectro at 1,000 miles I now have 17155 miles on it.
    Like all of us I have a choice on what products to use and I chose Spectro. I think it is a good product and it works for me. I ride all over the country and in all kind of weather and feel that this product is what i want in my engine.
    Many years ago I was told it is cheaper to change your oil than rebuild your engine. I have added to that using the best oil for the application is worth what ever it costs.
    I do my own work and service and do pay serious attention to the operation of my motorcycle. That way I can spend less time working on it and more time riding it.
    I liked the oil so much I recently tried some of the polish, YEA Polish and it works great. Not sure why a oil company makes polish But it also does the job.

  10. 10 Harley Chug Aug 27th, 2010 at 4:21 pm

    Have been following the advise that came with my S&S motor and using Mobil 1 V Twin Full synthetic since day one.

  11. 11 jack Aug 27th, 2010 at 10:55 pm

    Think of oil like a cocktail. Spectro be some good bartenders.

  12. 12 Mike Tomas Kiwi Indian MotorCycle Co Aug 28th, 2010 at 9:30 am

    Rollin, Nice article addressing some good facts. I commend you on addressing those questions being asked. Very professional. Keep up the great work and high quality products. Quality counts.

  13. 13 jesse Aug 31st, 2010 at 5:22 pm

    Rollin, – Good info. Thanks for taking the time to contribute on this article and respond to the questions.

  14. 14 Terry Purdom Sep 12th, 2010 at 7:46 am

    Yesteday my husband had to take oil out of my Harley 883 today he checked before a ride and said it was making oil! “that can’t be good”?

Comments are currently closed.
Cyril Huze