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Discussion Starter #1
Bike not revving past 12k could a weak battery make my fuel pump run with lower pressure??
 

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YZFR6... ooodles of HP
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Old plugs, weak coil (s), dirty fuel system, weak fuel pressure.
 

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Buy this fuel pump for my R6.
I hope it solves the problem...

FPF T35 Intank Fuel Pump For Yamaha YZF-R6 2006-2007

s-l1600.jpg
 

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YZFR6... ooodles of HP
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Cam timing?
 

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Then you would have been effectively firing on the exhaust stroke. Should not have ran at all unless you were dieseling. Hrmmmmm.
 

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So both of the cam timing marks were set to point at one-another while crank was on TDC mark?
375115


The ECU in my previous vehicle would fire based on crank signal. Fueling would be "influenced" based on cam signal. If cam signal were lost/faulty, it would ignore cam and fuel based on crank. But it would waste fuel, injecting on the exhaust cycle in addition to the the combustion. It was a wasted spark design so TDC didn't matter. (crank rotates twice for every single cam rotation)

Does the R6 have a "wasted fuel" strategy by default?

Did first gen still have "points"... that is, a mechanical distributor for the ignition system?

<<..........
Am I 180 Out?

People ask this a lot when they have trouble getting an engine running after they’ve set the cam timing up, or when they bring the piston up to Top Dead Center and find both valves open. This is the common mistake we mentioned earlier, and it's one of the things that's more easily understood when you have a good grasp of the complete cycle. It’s more of a car thing, but if you have an old classic four-stroke from the ‘70’s or before that uses cam driven breaker points, it’s sometimes possible. These days, the answer is usually, “no.” The old way of connecting the ignition to the engine mechanically, that of using a distributor or some other device driven at half speed by the cam, allows a mistake in assembly to be made. A mechanic could position the engine at TDC, and if not careful to check, he could position the ignition trigger to fire during the exhaust stroke instead of the compression stroke. This was referred to as being “180 degrees out” because the distributor or point plate was 180 degrees away from the correct position on the camshaft because of this. Actually, going by the crank, the ignition timing was 360 degrees out.

But with the ignition trigger located on the crankshaft instead, as is the case with virtually all modern single cylinder dirt bike 4 strokes, that’s not possible. Without the cams connected to the crank, one TDC is exactly like another; the rod’s at the top, and the spark signal is given as the crank gets there, every time. So, the only thing that determines which stroke is which is the camshaft(s), and how they are positioned by the assembler. That’s why the service manuals for such engines make no mention of checking for which of the two different TDC’s is used. In operation, there is a second, "wasted" spark that happens near the end of the exhaust stroke. ..................... >>
 

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Then you would have been effectively firing on the exhaust stroke. Should not have ran at all unless you were dieseling. Hrmmmmm.
Yeah crank mark was at TDC just had the cams 180° not sure how it was running as well as it was
 

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That would suggest that the R6 operates on a "wasted fuel" strategy... maybe due to cam sensor issue or for "improved" NOx emissions. Probably explains how a 400lb machine gets such terrible mileage. Can you imagine the mileage if it weighed as much as car... which at times can get similar mileage?
 

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YZFR6... ooodles of HP
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I dunno.. i got 45 - 60mpg instant fuel consumption stock. Which was 150-160mi to reserve (3.5g) now with my fuel mapping I'm at 148mi to hit reserve. Which puts it in the 45mpg range. 148/3.5 but I'm not calculatin'. Me lazy. Been auto tuning my maps for a while.

You mean waste spark. Like my 1983 vf750f intercepter does.
 

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Somehow forgot the 600cc is port-injection, not direct. Fuel doesn't enter until the intake valves open. Injector timing isn't nearly as critical. Pretty much all modern engines are wasted spark design.

Re mileage, to put it in perspective, my prior car on a 1.9L SOHC engine would pull low to mid 30s. Some of the folks in the forum would be able to wring high 30s out of it. But that car weighs 7.5 times as much as this motorcycle. My current 1.6L GTDI probably (not calculating - just relying on computer) does high 20s, low 30s; it might weight a couple of hundred pounds less. Although it helps, somehow weight just doesn't seem to be THE factor for mileage. We're in a valley. LOTS of inclines and declines.

Yep, post-mod we're getting similar mileage. Your generation has an oxygen sensor doesn't it? That opens up a whole new world in terms of potential fuel efficiency. Yamaha quotes the 2020 model at 42MGP. I looked up the FJR-1300ES and it's even less at 36MPG.

All matters considered I guess the greatest factor is how much air you're pumping. Even at idle there's quite a lot exiting the R6 tailpipe.
 
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