High mileage oil results
When I got my 99 Softail Custom last year, it had Castrol GTX 20-50 in it with 17,000 miles on it. I changed it to Mobil 1 VTwin, but I think I will change it back to Castrol. Money is not the issue here, it is simply the fact that EVO's seem to run a long time on Castrol.
If some of you guys with high mileage running synthetic will post your results, I would like to see what you did. I am sure there are some out there that have some high mileage bikes with synthetic also, but it looks to me like Castrol works, and works well. Just my 2 cents.
I don't believe syn oil is necessary for anything but an out and out racing engine.
Second, MP changed his oil every 2500-3000 miles, which IMO is a requirement if you use dino oil. Synthetic oil resists oxidation better than dino, and any of these can go at least 5k miles between changes. I did two tests on my old RK Evo, one in summer and another in winter, and was told the oil could handle 7-10k miles before the additives were depleted, including those that contribute to TBN. Thus, since you can buy a high-quality synthetic for <$5/qt. (Mobil 1 15w50), there is no monetary reason to use dino oil, which in time will form sludge regardless of the change interval.
Synthetics tend to have better lubricity than dino oil, partly due to superior additives, and that translates into longer engine life. It also adheres to metal better and allows easier starting, which also contributes to longer engine life. Most engine wear occurs in the first few seconds of starting a cold engine, and if there is more residual lubricant on the metal surfaces at that point in time you incur less wear.
To the OP, Castrol GTX 20w50 is an excellent dino oil, and I use it during the break-in period of all my new bikes. The synthetic regimen starts at about 2k miles for me. If was to select a dino oil to use, this one would be at or near the top of my list, but I would not use anything but synthetic in a car or bike that you plan on keeping for years that will accumulate high mileage.
Last edited by iclick; Feb 17, 2010 at 11:41 AM.
But Castrol GTX 20w50 is not a real robust oil compared to other oils. If you want a really decent dino oil then try Brad Penn.
www.bradpennracing.com
You have to find a local distributor in your area but it has the best specs for a dino oil I have seen yet. It also has an HTHS of over 6 for the racing 20w50 which is a very tough robust oil.
Second, MP changed his oil every 2500-3000 miles, which IMO is a requirement if you use dino oil. Synthetic oil resists oxidation better than dino, and any of these can go at least 5k miles between changes. I did two tests on my old RK Evo, one in summer and another in winter, and was told the oil could handle 7-10k miles before the additives were depleted, including those that contribute to TBN. Thus, since you can buy a high-quality synthetic for <$5/qt. (Mobil 1 15w50), there is no monetary reason to use dino oil, which in time will form sludge regardless of the change interval.
Synthetics tend to have better lubricity than dino oil, partly due to superior additives, and that translates into longer engine life. It also adheres to metal better and allows easier starting, which also contributes to longer engine life. Most engine wear occurs in the first few seconds of starting a cold engine, and if there is more residual lubricant on the metal surfaces at that point in time you incur less wear.
To the OP, Castrol GTX 20w50 is an excellent dino oil, and I use it during the break-in period of all my new bikes. The synthetic regimen starts at about 2k miles for me. If was to select a dino oil to use, this one would be at or near the top of my list, but I would not use anything but synthetic in a car or bike that you plan on keeping for years that will accumulate high mileage.
There ton's of opinions and no "right answer" for what is best...I have a friend who has 80k+ on his 2003 Ultra. He uses a famous named, pyramid scheme sold synthetic oil and changes his oil every 10k miles...It works for him.
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I've told this story before and will do it again now. About two years ago two friends collaborated to perform big-bore upgrades on their 2000 EG's. One of them had been running Amsoil 20w50 MC oil and the other Mobil 1 15w50 (not V-Twin), which costs half as much. The former had 50k on the clock and the latter 60k at the time. When the jugs were removed and internal parts inspected neither engine showed any noticeable or measurable wear, and even the piston coating was still intact on both engines. The cylinder walls still had the hone marks showing. I dare say that any synthetic oil would have done as well as these, and the point is that you don't need to buy the most expensive oil to get the best lubrication.
Last edited by iclick; Feb 17, 2010 at 08:42 PM.
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