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Discussion Starter #1
Does anyone know if the oil pump is variable rate? In another post GLS states that the oil rate should be 60-80:1 at 6000 to 7000 rpm. I would asume that to mean that at lower throttle, the rate would be closer to 100:1 and at WOT it would be closer to 50:1 . I know for example that my Merc. Back Max outboard is 100:1 at idle and 50:1 at WOT. I have noticed that peoples oil usage varies and it seems to show a relatinship to the way that they are riding. I just completed a ride and my oil use was about 85:1 but almost all of the riding was at 5000 to 6000 rpm. Thats still lean but if the pump is variable rate then maybe it still isn't critically bad. Any thoughts?
 

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I'm getting really confused and frustrated about the oil ratio of my F7 SP. Each time I check it I get dramatically different oil use ratios.

On the river using 5.65 gal = 76:1,
In the mountains 8,000+ feet using 18.515 gal = 52.6:1,
Ditch and lake riding using 9.002 gal = 83:1,
Michigan U.P. trail riding using 28.33 gal = 96.7:1 (370 miles @ 13 miles per gal)

This is the only data I've kept track of so far. I'm trying to dial it in around 70:1, but I get these wild ranges in oil use ratios. I'm tempted to disconnect the oil injection and go back to premixing. That way I'm always running at a constant ratio that I can control.
 

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Jeff: Can you recall on how hard you were riding at these times with respect to RPM etc. The rates appear to be different for the different throttle positions. As a result it may be difficult to get consistent results to set up the pump .
 

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The pump is a variable rate pump. But a thing to consider is the output of a pump at any one position can range 25% from the high side to the low side and be considered a good pump. Quality oils can handle 80:1 at full throttle no problem. I think this turning up the oil pump is a band-aid solution to a lean fuel and cooling problem
 

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Manfire & 720,

The Michigan U.P. trip was with young riders, so the overall pace was slower, I'd say average speed 40 - 50 mph. So a lot of mid range throttle or less. The other rides were all "in and out" of WOT all the time while riding hard. The mountain ride was probably the most WOT due to powder riding, but calculated to be the most rich ratio. I assumed the high elevation with less oxygen was a contributing factor? Maybe it was due to the WOT position? Regardless, I would prefer a constant oil ratio, for optimum performance under all riding extremes...
 
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