FJ1200 3 CV oil use

[TomJK]

Hi
Read a lot about the FJ since joining, my FJ is using quite a bit of oil, about 1 liter in 1000 km, Guess that is a quarter in 600 miles, but only when I wring its neck, on the German Autobahn, for 4 hours, on speedo it hits 270 (165+) without a problem, do not think engine is worn...when touring, not going faster, around 130 (85 mph) it uses very little oil, I guess when engine gets real hot oilfumes will be blown into the airbox and that causes the oiluse, or am I mistaking?I do not see blue smoke.
I am on the Autobahn a lot, while I live in the Netherlands and my (German) wife lives in Germany, it is 330 mile trip, 90 percent of it is Autobahn....takes me 4 hours, that is including 2 tankstops.
Cheers, TomJK.

[Pat Conlon]

What oil are you using Tom? What main jets are you running?

If your compression #'s are good, no smoke, and oil usage at 85mph is fine, I think you are ok.
Our air cooled engines use larger cylinder wall clearances than today's water cooled bikes and thus we get a lot more crankcase blowby than today's bikes. Oil usage at sustained high speeds is normal and expected, but 1 liter per 1000km seems like a lot....but if the engine is at 9500rpm for that time, is it really? I don't know. I have never ridden at 9500 rpm for an hour or more...sure sounds fun.
No where in the US can we attain the amount of 'time at speed' that you can on the autobahn. Sure, we can do 165+ on deserted highways, but not for that long of time. We have some open land interstates where we can ride 90+mph for several hours, but again, nothing like the autobahn.

That said, I find that certain oils burn off faster than other oils.
The most durable oil I've found is a full ester stock based synthetic made by Redline Oil 15w-50.

Give that a try, see what you think.

Cheers, Pat

PS:  Make sure your main jets are fat enough at those speeds. At 9500rpm lean mixtures burn hotter and use more oil. Instead of the standard 'seat of the pants' (aka butt dyno) technique for selecting main jets, strap your bike to a eddy current dyno, stick a O2 sensor in the tailpipe and wind her out and let her sit at 9.5k rpm and then see precisely what the fuel/air ratio reads.  
Remember, the stock factory jetting is set on the lean side.

A question for Chris, Randy, Mike and all our other engine gurus: At this type of duty cycle, WFO @9500 rpm sustained for an hour or more, what fuel/air ratio would you run, 12 to 1?
I know I would sure invest in some stronger aftermarket rods.

[Old Rider]

I changed oil 2 days ago and had used a little more than 3 desiiter on 3576 kilometers mixed driving.Yamalube 10w-40 mineral oil.

[CutterBill]

Wish I could instrument this guy's bike and get some numbers for Cylinder Head Temp and Oil Temp at those speeds. Would be interesting to see...
Bill

[fj1289]

Bill, I know on the land speed bike my cylinder temps would DECREASE during a run despite a large shot of nitrous being used!  Now, that said, there could also be some error in my method of measurement - used a Saturn water temp sensor dropped into the cylinder head fins on the exhaust side.  It may have been getting more airflow between the fins and reading cooler than the "meat" of the head.   

Pat, I'd assume 12.5:1 to 12:1, but would defer to Randy - they get these engines HOT HOT HOT in the cars.   Don't know if they try to riches them up to cool the combustion chamber a bit, or if they accept the heat and tune it for max power?

[TomJK]

Hi
Thanks for reply, I also own and ride a Kawasaki ZX10R, C1, first generation, do high speeds with that, no or little oiluse in that, I guess it being watercooled and build much later, is the reason for it, I do not go 165 all the time, but sometimes close to 150 on longer stretches of clear Autobahn, at 270 it runs just under 9500 rpm, use 18/38 teething and Ester based semisynthetic 10W40 in all my bikes, got the Kawasaki Z900 (2019), the ZX10R (2004) with over 60000 miles on clock, and the FJ, own it 3 years now, done 20000 miles on it since I got it, its now got 48000 miles on clock.
Cheers, Tom.

[T Legg]

Hi
I do not go 165 all the time, but sometimes close to 150 on longer stretches of clear Autobahn,

Tom how does the high speed running affect your tire wear? The reason I ask is because my last rear tire wore down to the threads showing (I run bias ply sport demons on stock rims) in only 2,400 miles of use. Normally these tires on my bike will barely make three thousand miles untill bald but not yet worn to threads showing. The only difference on my last tire is that I was using it daily to ride back and forth on a long open highway where I was reaching 150 mph indicated (probably around 135 to 140 mph actual speed ) on a regular basis.

[TomJK]

Hi
Tyre's last surprisingly well, considering the long fast use....I got 17 inch rear wheel, put a Michelin Pilot Road 5 on it, very good Tyre! I've done over 6000 miles now, still legal.... tried the Michelin Pilot Power, lasted about 4000 mile.
Cheers, Tom