Fuel Injection

Fast Eddie said:
What I meant was, there’s no feedback, no correction. It injects what it’s set to.
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Seems it would need some type of control for rpm and timining/duration of injection pulses? I assume these were common rail type injectors, not direct to compression chamber? Still would require some controls I'd expect.
 
I have a 650 Royal Enfield, I understand fuel delivery but totally ignorant to the electronic part. Early stuff partially ran off the tach cable, newer stuff had pulses from the distributer and the NEWEST stuff reads pulses from the crank.. It would be great to find a wrecked Royal Enfield for working parts, we will have to keep our eyes open for one. Are you listening Tony A?? And NO I'm not tearing my bike apart to experiment! LOL
 
mean gene said:
I have a 650 Royal Enfield, I understand fuel delivery but totally ignorant to the electronic part. Early stuff partially ran off the tach cable, newer stuff had pulses from the distributer and the NEWEST stuff reads pulses from the crank.. It would be great to find a wrecked Royal Enfield for working parts, we will have to keep our eyes open for one. Are you listening Tony A?? And NO I'm not tearing my bike apart to experiment! LOL
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Which one do you have? How about a review in the RE section? I'm sure plenty people would be interested.
 
Tornado said:
Seems it would need some type of control for rpm and timining/duration of injection pulses? I assume these were common rail type injectors, not direct to compression chamber? Still would require some controls I'd expect.
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Bosch K Jetronic. Continuous injection controlled by a mechanical airflow sensor connected to a fuel distributor which adjusts fuel flow. Used on Volvo, Volkswagen etc back in the 70s.
 
Tornado said:
So how did early types function before there were micro computers to sense pressures, temps, O2 levels and control injection?
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They were mechanically timed to the crank so the injection events were just before the inlet valve opened, the amount injected was determined by the throttle opening. So at its most basic not much forward from a carb unless you were rolling over into a dive and your carb float got all confused ;)

www.pistonheads.com

What is mechanical fuel injection? PH Explains

Explore the basics of the predecessor to electronic fuel injection
www.pistonheads.com www.pistonheads.com

Things progressed as sensors and other bits and pieces were added.
 
kommando said:
They were mechanically timed to the crank so the injection events were just before the inlet valve opened, the amount injected was determined by the throttle opening. So at its most basic not much forward from a carb unless you were rolling over into a dive and your carb float got all confused ;)

www.pistonheads.com

What is mechanical fuel injection? PH Explains

Explore the basics of the predecessor to electronic fuel injection
www.pistonheads.com www.pistonheads.com

Things progressed as sensors and other bits and pieces were added.
Click to expand...
So for a classic bike, would a mechanical feedback system for FI be worth the simplicty?
 
Tornado said:
So for a classic bike, would a mechanical feedback system for FI be worth the simplicity?
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Does one exist for a twin cylinder ? not sure one was ever made, unless you take one with a single injector firing into the branched manifold and blank off 2 of the 4 cylinders. Even if it was then I would have thought a modern ECU would still be the way to go as the parts are much cheaper and the software for custom install exists.
 
I've got a headache now and am willing to settle for a pair of new 932's to settle this matter. They don't even have to be premiers.
 
Fast Eddie said:
Absolutely agree.

Plus a race cam, raised CR, and ideally a 920 conversion.... :D
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I'm in agreement. The bragging rights are all fine and good, and I chased that idea for awhile. But I'm fairly happy with the bike I built, oversize intake conversion a'la Mr Comstock, WEB 312 cam, balanced crank with Carillo's, 10.1 CR, and bolted to a lowly set of Amal 32's. She goes like stink for a road bike. But is still very streetable and smooth. A set of Keihin's was on my list but honestly, at this point I doubt I'll pursue them.

I've got my Speed Triple for going crazy fast, and even her 135HP is fairly tame by today's standards
 
One thing I have never played with is the taper on the carb needles. I always use the leanest and I use fixed ignition advance. But there is probably something to be gained from better control of the mixture and ignition advance under all circumstances. In my situation, it does not matter much because I use methanol fuel. But if I raced using petrol, I would think differently. Petrol is much more difficult to get right.
If you go back in history. In the 1950s in Australia we used methanol when racing Manx Nortons. When our riders went to the UK, they did well because they were used to the speeds. But the Britsh could get their Manx Nortons going as fast using pool petrol as we could in Australia using methanol. Doing that with carburetors takes extreme patience.
 
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Fast Eddie said:
IMHO no.

Mechanical injection is crude and I would suggest that modern carbs like the FCRs are far superior.
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I disagree.
The Bosch inline fuel injection pumps are absolute marvels of engineering.
Like used on Messerschmitt, many Mercedes 6 cyl. and V8, Porsche racing cars..
They compensate for rpm, temperature, air pressure, altitude..
Drawback is they are very complex and expensive.
I still have several lying around.
Now, if only I could reproduce the 3-dimensional cam..

Fuel Injection
 
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Good job it is not Lucas fuel injection, in which they dabbled their feet in making one for a Maserati car, they never made one again.
 
With a carburettor, you'll be able to ride your bike until petrol disappears.
With EFI you only have a few years riding until the electronics becomes obsolete and impossible to repair.
Spares supply for the old English bikes is indeed very good.
I have problems with the Japanese race bikes from the eighties. Spares often unobtainable.
 
ludwig said:
I disagree.
The Bosch inline fuel injection pumps are absolute marvels of engineering.
Like used on Messerschmitt, many Mercedes 6 cyl. and V8, Porsche racing cars..
They compensate for rpm, temperature, air pressure, altitude..
Drawback is they are very complex and expensive.
I still have several lying around.
Now, if only I could reproduce the 3-dimensional cam..

Fuel Injection
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I’m not arguing that the high end stuff is not technically fantastic. It is! And neither would I expect a ME109 to be improved with a concentric carb... even a Premier!

Could a Norton be built as a ‘package’ to bennefit from a purpose designed high end FI system? I would agree the answer is yes.

But this thread started out hypothesising about the benefits of fitting a low cost, low performance, Royal Enfield system to a Commando. And my hunch is it wouldn’t offer any advantage over well set up FCRs or similar.
 
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