|
These two clues prompted me to test the differences between oils regarding best timing: 1) when lit on fire synthetic oil makes the smallest flame and mineral oil makes the largest flame which means they have different flamability 2) when analyzing the molecular composition of petroleum products the range is from very low carbon chain molecules of gasoline, to group 1 mineral oil, then group 2, then group 3, then groups 4 and 5 (synthetics). This chemical analysis gives backup to the first observation. So there's a long street uphill in my town which keeps my air cooled 48cc from reaching top RPM and so I got the idea of adjusting the ignition timing to see which timing gives the best uphill RPM (best power). I have an adjustable CDI of my own design. The result showed a maximum difference of almost 7 degrees between one type and another. This means: 1) When changing engine oil type you need to retest for best timing for best peak power or best powerband. 2) it's possible that the best power can be had by using a fast burn oil with a high RPM engine, and a slow burn oil with a low RPM engine. Engine Oil Types: Fully mineral oil, Synthetic/Mineral blend, Fully synthetic, Synthetic/Castor blend, Fully castor oil. Here's the graph results of the 5 main engine oil types.    The difference in needed timing was 3.3 degrees between #1 and #2, or #2 and #3/#4. The difference in needed timing was 6.6 degrees between #1 and #3/#4. So if you have adjusted your timing to what you like best and you then switch type oil then by this info you know to also readjust your timing. For Example: Yamalube is mostly group 2 with 29% group 1, so if you switch from that "all mineral oil" to another type oil such as semi-synthetic then you know to recheck the timing. How To Set Ignition Timing: 1. Use a genuine NGK spark plug, not a cheap copy, of the heat range which you think is right for your engine which will be 1 or 2 #s higher than the stock recommendation if you have modded it for higher RPM. 2. Try different main jets and keep the one that is the biggest w/o causing any sputtering on slight downhills (when engines like lean jetting). If this causes sputtering mid throttle then lower the needle 1 or 2 notches. 3. Try different ignition timings, not changing it by more than 3 degrees each time. To know how far to move the stator coil plate (at its outer edge) for 3 degrees just multiply 0.0262 x stator coil plate diameter. If you ride mostly mid RPM then set it for best power there, and if mostly riding high RPM then set it for best power there. 4. Then look at the spark plug to see where the color change line is on the ground electrode. If closer to the end than at the halfway distance (halfway along the electrode) then the NGK heat range # is too high. And if closer to the weld point than halfway then it's too low. Click here to access my engine oils page which tells the % of each type oil in each engine oil. Engine Oils fully mineral oil: Amalie Pro 2T : 99% group 2 mineral oil Amalie SynPlus: 82% group 2 mineral oil Bel-Ray Mineral 2-Stroke Oil : 90% group 2 Bel-Ray SL-2 : 30% group 2, 35% group 1 Castrol Go!: 70% group 2, 20% group 1 Yamaha Yamalube 2R : 67% group 2, 29% group 1 PJ1 Goldfire Pro Racing : over 35% group 2, under 30% group 1 Spectro Oils 2T : 75% group 2, 7% group 1 Golden Spectro : 80% group 2, ~ 5% group 1 Oils with less than 30% group 1 oil: Mineral Oils Golden Spectro, Castrol Go!, Yamalube 2R, Spectro Oils 2T, PJ1 Goldfire Pro. Semi-Synthetics Motul 510, Motul Scooter Expert, Motul 710, Motorex Cross Power, Repsol Moto Off Road, Maxima Premium 2, Lucas Semi-Synthetic Oils with less than 21% group 1 oil: Mineral Oils Golden Spectro, Spectro Oils 2T, Castrol Go! Semi-Synthetic Oils Lucas Semi-Synthetic, Motorex Cross Power, Maxima Premium 2 Mineral Oils with no group 1 oil: Amalie SynPlus, Amalie Pro 2T, Bel-Ray Mineral Oil. Semi-Synthetic oils: Putoline MX5, Castrol A747, Red Line AllSport (not recommended due to 60% group 1 oil), Lucas semi-synthetic, Royal Purple HP 2-C, Maxima Premium 2, Motul Scooter Expert, Amsoil Interceptor, Amsoil Dominator, Putoline MX9, Motorex Power Synt, Motul 710, Motorex Cross Power, Motul 510, Maxima Scooter Pro, Castrol Power 1 Racing, Maxima FORMULA K-2 (7.5% mineral oil), Motul 800 2T Off Road and Road Racing (6% mineral oil) Fully Synthetic Oils: Maxima Super M, Bel-Ray H1-R, Silkolene Comp 2 Plus, Silkolene Pro 2, Castrol Power1 XR 77, Klotz R-50 Techniplate, Honda Pro Honda HP2, Motul Kart Grand Prix, ELF HTX 976+, Repsol Moto Racing 2T Synthetic/Castor Oils: Maxima CASTOR 927, Silkolene Pro KR2, Penrite 10 Tenths Race Castor Fully Castor Oils: Klotz BeNOL, Dumonde Tech Racing Castor, Blendzall Ultra Racing Castor |