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fuel injected 06 crf

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Anyone heard of the o6 crf 450's being fuel injected. Is there any truth to this?

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I havn't heard but someone I spoke with pointed out a potentiel issue with this. A fuel injected engine is then regulated by a computer. If you change the pipe or other upgrades the computer may not be able to adapt. Don't know if this is true, hopefully someone does.

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Im sure it would be just like a crotch rocket the has FI. When you buy a pipe you also buy a power commander. Its just commom knowledge in the street bike world.

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I havn't heard but someone I spoke with pointed out a potentiel issue with this. A fuel injected engine is then regulated by a computer. If you change the pipe or other upgrades the computer may not be able to adapt. Don't know if this is true, hopefully someone does.
There are two primary types of fuel injection (FI) systems; those with a mass-air sensor and those without. FI systems equipped with a mass-air sensor are more expensive and complex, but they actually measure the engine intake air flow so that the amount of injected fuel is changed to accommodate air flow changes accomplished (within reason) through intake/engine/exhaust modifications.

FI systems without a mass air-flow sensor infer air flow by measuring throttle position, manifold air pressure (MAP), air temp, etc., and then looking up a calculated required fuel flow in an internal fuel map "database". The fuel map is strongly dependent on the exact configuration of the intake/engine/exhaust so these systems are less capable of adapting to intake/engine/exhaust modifications. As a result, significant intake/engine/exhaust modifications often require changes to the fuel map.

Changing fuel maps is relatively easy with systems such as the Power Commander, but accurately adjusting the fuel map often requires some dyno time. Given the lower weight, cost and complexity of the latter systems, initial FI systems for off road bikes (as did early automotive FI systems) will likely not be equipped with a mass air-flow sensor. Future systems (as do many current automotive systems) will probably incorporate a mass air-flow sensor for increased accuracy and flexibililty.

Although either type of FI system would be a major step ahead of carbs, the mass air sensor FI systems will be fantastic; especially when they add VTEC, etc.! From the Hondanews website:

"The VTEC (Variable Timing and Lift Electronic Control) system uses two roller arms per pair of intake valves. During low-rpm operation, intake air is drawn almost exclusively through the primary intake valve, thereby creating a very strong swirl effect to maximize combustion. At higher rpm, the secondary rocker arm engages the primary roller, opening both intake valves for the same lift and duration, substantially increasing airflow into the cylinder and boosting performance."

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Also, from the Keihin site:

"Future EFI Plans

Due to tightening emission regulations worldwide, the world demand for EFI systems will continue to grow. Honda and Keihin will partner to equip all Japanese market Honda scooters with PGM-FI systems by end of 2007, and most Honda motorcycles by end of 2010. Keihin is continually developing and building new and advanced eco-friendly engine control technology."

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Dont forget with EFI comes massive increases in power and FUEL ECONOMY.

BMWs for example get massive kms/per litre.

Does anyone know the story behind Montessa using Honda Motors? Does Honda own montessa?

EFI cant be that fra behind now - that Keihin system looks well sorted and truthfully as long as it's all tucked out of the way, should be no problem.

Imagine also electronic shifting from a button on the left handlebar and also fly by wire throttle.

So many weight savings on bikes that are already light!!!

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That Montessa thing is badass looking.
Yup, fuel injection without a battery. Way cool.

I download the service manual for it and it looks pretty nice. The flywheel is HUGE. They say the thing is derrived from CRF250. Its a 4 valver but has rockers (with screw adjusters) for both intakes and exhausts. I didn't see what the valve material is. No mention of Ti or SS or anything for that matter. The only thing that looked like a PITA is that the whole left side cover has to be removed to change the oil filter.

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Dont forget with EFI comes massive increases in power and FUEL ECONOMY.

Try telling that to an RC51 owner! I had one, and didn't like to ride too far out of sight of a gas station! :cry:

I don't think power or economy is necessarily improved, the main advantage is you can "jet" it electronically instead of having to pull apart a carb.

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