Agreed.

Synthetics are all good, I just choose Royal Purple for my vehicles and stock it in our shop because they're local.

I try to support my neighbors.

 

Funny again I cant find anything but Lucasoil around here in Baytown.......

 

$19qt. Royal Purple Max-Gear 75w-140 in tranny (09 Ultra).....

Whines just the same. Glad you all like it.

chuck

 

$19.00 a quart? jeez louweez..........

 

I've been using Amsoil for twenty plus years. For 20 degrees more, might be worth a try.

 

Always ran Amsoil in the HD...ran RP in the sport bikes. Figured that RP was really only good for the higher revving engines (so I heard).

I do run RP in my Silverado SS and Mobil1 in the Burban...tried Lucas in the Burban and hated it.

What was the temp difference running the Mobil1 in the HD? What are the (real) temp difference numbers running the RP from Amsoil?

 

I believe the temperature-reduction claims. I've used RP for about 15 years in all my vehicles, and I can give you some evidence on the subject of cooling. Our weather has been 95-100° for about the past six weeks, and in these conditions my bike runs about 200° oil temp and 225-235° front-head temp when running >45mph. When in the city and the traffic grinds to a crawl it might reach 230° OT on rare occasions, but hasn't gotten above ~220° yet this summer. Head temp has hit 300° on occasion, but usually stays <280° even in city riding in these weather conditions. The oil cooler helps in keeping OT and ET's in control, but I do think the oil is a factor too. I'm often amazed at how cool this bike runs in these conditions, and I'm running near stoich (14.5:1) in the cruise range, which is near stock and not a recipe for keeping an engine at its coolest operating temperature.

A friend has a '10 SG and much to my dismay his OT is running even cooler than mine, and he doesn't even have an oil cooler. He runs RP 20w50 "car" oil, not the more expensive MaxCycle. I mix 2.75:1 RP 20w50 "car" oil and RP Nitro 60 racing oil, this after having a long discussion many years ago with an RP guru about maximum protection and cooling. This was the mix he used in his MC and he claimed 200% greater lubricity and increased cooling over the 20w50 alone. I don't recommend this mix primarily because of the cost of the racing oil, which is about $17.50/qt. and is only available in the 5-gal. pail. The last time I looked at a pail of this stuff was $350, and when I buy I split it with a friend who is a nutcase engineer who knows about this oil. It is formulated for nitro-methane-burning dragsters and is loaded with anti-friction additives, and who knows what else. I ran some informal viscosity tests on it and at 0°F it flowed better than RP 20w50 and Mobil 1 15w50, but oddly enough was a bit slower at 32°.

It is indisputable that RP is an excellent product, but there are other fine oils on the market as well. I use it because of its reputation as well as my own experience, and also because I know an RP distributor and buy the oil by the case or 5-gal. pail at dealer cost. I choose the larger quantity because it is cheaper. Also, he delivers it to my door usually the same day I order it.

I ran this oil mix in my '96 RK and after 106k the heads had never been removed from that bike, and the only engine work done was a cam upgrade in '98. In '98 my CCP was 155/160 and in '06 at last check at >100k miles it was 160/160, and oil consumption had not changed. That bike ran so cool it worried me, and OT's almost never exceeded 180° even in city riding. At 120k the new owner replaced the engine with an S&S, so we'll never know how long that motor would've lasted. Not sure where it is today, but it's probably still running.

 

Thx...good info. So you wouldn't know the change from Amsoil to RP?

 

I switched to Royal Purple in the motor and tranny, boy what a difference. Runs cooler, way quieter, shifts smoother, and I think i picked up a tad on the top end. I'm not positive what type of oil was in it by the guy that built the bike up before I bought it though.....