The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: mightywind on April 14, 2007, 08:35:41 AM
-
Has anyone experimented with a higher octane gas in their R65? I usually use 87 and I'm wondering if upgrading would give any benefit?
-
If your timing is set to where it belongs and you get no pinging (or pinking depending on which side of the pond you're from) under load the answer is no. The only benefit is to the refiner's wallet. I suppose that if you have had to retard the timing to get rid of some spark-knock then putting the timing back where it belongs and running a higher grade might be of some benefit.
-
When I bought my first R65, I thought I was doing the bike a favor by putting only premium in the tank. Somehow, I thought that "European bikes cannot run on anything but premium". Duh....
However, now that I am slightly more "ed-u-ma-cated" ::) I have learned that putting high-test in the tank just cost you more at the pump (at least on older Airheads like we have). So I ended that expensive practice pronto. Since I got Britta in June of '03, she's gotten regular unleaded at every fill up and both she and I are happy! ;)
-
I use the cheap stuff.
-
I use regular ( 87 octane) during the cool weather here in Phoenix, but once the temps are above 100 F., I need to use mid-grade ( 89 octane) or premium (91 octane), or I get what sounds like a diesel engine on heavy throttle application.
-
Hmmmm I thought the riders manual said...Oh well time for a bit of experimentation. :o
-
The owners manual DOES specify premium but the only thing we have that needs it is my '95 RT, and it pings under heavy load even with that!
-
The sticker on my rear fender specifies regular fuel, minimum research octane number 91. Here in Oregon, the octane rating on the fuel pumps is the research octane number plus another type (can't remember what it's called now) divided by two, but the research number is almost always higher, so the 87 regular we have around here works fine. No pinging, and trust me, from riding my Triumph I know what that sounds like. :(
-
I believe US pump rating is computed from (research octane+motor octane)/2. Looking at the owners manual I have shows the requirement is a reseasrch octane of 98 or motor octane of 88. But that really doesn't matter, run what it's happy with! My wife's '84 seems perfectly happy with Regular, my nekkid '81 R100RT is fine with Plus, while my '95 R100RT will ping under load with Premium when it starts to get warm...
-
Ditto to what Bob Roller said. I don't know if it's the special summer formulation fuel we get here in Phoenix but in the hot weather mid / high octane seems to werk the best in my unmodified engine as well.
Rich
-
I use bog standard unleaded with a squirt of Redex lead replacement stuff in to a full tank once every week or ten days.
I've got unleaded valve seats these days and the Redex is probably more a peace of mind thing than anything else. Until For two years before I converted the heads when leaded petrol was removed from sale I ran a fuel cat (from motorworks) in the tank which worked fine. Or seemed to, as the seats did not seem anymore buggered than ones run only on leaded 4 star.
-
I use regular 87 octane with no problems. Also run it in my R27 with no problems and it has been on a regular diet of 87 for a long time. I would be hesitant to use a high grade these days. Was filling up a year or so back, when the gas supply truck was unloading. The drive came over, we were talking cycles. I asked if they sold much high octane these days. He gave a weak little smile and said he had done nothing more than a slight top off ever now and again to the high octane tanks for at least a year. He said that demand for premium was way down. So, I am thinking if this gas has been sitting in there for who knows how long.....what kinds of problems, gunk, water condensation...is it collecting in there. Maybe none but on the other hand........................
-
I also run "regular" 87 octane fuel in my R65, and it seems to be fairly happy with it.
I've also been putting in some lead additive every couple of tanks until I am ready to
get the valve seats redone - it may be a placebo, but for now it seems to at least help
with my peace of mind.
My Kawi concours runs better on the 89 or 91 octane fuel. My '88 R100RT also ran
much better with less pinging on the mid-grade or premium grade fuel. It had the
stock jets and exhaust, and I think that they were running those larger jugs pretty lean
anyhow. On hot summer days or with lots of mountains to climb, it might do some
pinging even with the premium gas in it, I seem to recall.
-
I think our bog standard unleaded petrol is 92, and the premium 98.
-
That's Research Octane, correct?