920cc with 270 crank

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HanaAna said:
Sequential injection not enabled yet. I want to try it at some point. I have missing teeth plate on the crank and cam sensor for syncing. With 270 ecu calculates correct timing for the first cylinder when we know the offset and then the second cylinder will have spark after 450 degrees. 360 is quite basic with crank sensor, I've done it with Yamaha XS650 and my Triumph NRE.
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Unsolicited thoughts:

I would leave the injectors batch firing, especially if it requires a bunch of work to make it fire sequentially. Sequential is better at low RPMs and might get you a little more mileage, but sequential turns to batch firing at higher revolutions, because it can't keep up on V8 engines. I'm not sure about twin motorcycles. I had 2 fuel injected twins, but all I did was make sure the throttle bodies were synced up and richen the California smog tune with bolt on parts. I don't know how the injectors were firing. I've run both sequential firing and batch firing retrofit fuel injection on a V8. I can't tell the difference sitting behind the steering wheel.
 
Schwany said:
Unsolicited thoughts:

I would leave the injectors batch firing, especially if it requires a bunch of work to make it fire sequentially. Sequential is better at low RPMs and might get you a little more mileage, but sequential turns to batch firing at higher revolutions, because it can't keep up on V8 engines. I'm not sure about twin motorcycles. I had 2 fuel injected twins, but all I did was make sure the throttle bodies were synced up and richen the California smog tune with bolt on parts. I don't know how the injectors were firing. I've run both sequential firing and batch firing retrofit fuel injection on a V8. I can't tell the difference sitting behind the steering wheel.
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I agree. Sequential needs SW configuration, I think. But at this point I want to make one change at the time and observe thoroughly the effects.
When you were running sequential, did you try to adjust the injection timing? Was just thinking out of curiosity how relevant the exact timing is with timed injection?
 
HanaAna said:
I agree. Sequential needs SW configuration, I think. But at this point I want to make one change at the time and observe thoroughly the effects.
When you were running sequential, did you try to adjust the injection timing? Was just thinking out of curiosity how relevant the exact timing is with timed injection?
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The only setup I've run with sequentially firing injection is the Edelbrock Pro Flo 4. The tuner software doesn't support injection timing parameters. Edlebrock has a lot of engineering resources, and did all the low level homework for their supplied engine configuration calibrations. Their tuner software keeps the low level stuff away from the consumer. The system is user tunable, but simplified and higher level.

920cc with 270 crank
 
Out of curiosity I measured 270 crank dry static BF, which appears to be very close to 50%. Weight 20.3 lbs.
So I think if I ever go back to 270, engine will be hard mounted to the frame.
 
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Heads up if anyone's interested. Had couple of runs with 360deg crank now and it feels great! Purchased same JS2 cam as I had earlier. Enough torque at 2000-3000 rpm for cruising, without vibration.... and pulls very hard at higher revs ;-D No bad vibrations at any range.
 
Test rode a Triumph Speed Twin a couple of days ago. Had a 270 degree crank.
No vibration, but then it had rotating balancing components.
Very impressive bike. 1200 cc, 96 hp, and only weighed ten pounds more than the Commando.
 
HanaAna said:
Heads up if anyone's interested. Had couple of runs with 360deg crank now and it feels great! Purchased same JS2 cam as I had earlier. Enough torque at 2000-3000 rpm for cruising, without vibration.... and pulls very hard at higher revs ;-D No bad vibrations at any range.
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That's encouraging to hear. Please keep posting your progress on the bike. This has been one of the more interesting build threads I've followed.

Ken
 
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