Carb vs Fuel injected

[the_lone_wolf]

Originally Posted by Keith1983

And the pointy blue ones are the fastest!

AMEN to that brother...

Originally Posted by the_lone_wolf

the only reason poorly implemented EFI is jerky is because of emissions regs, you could program the black box to provide exactly the same fuelling as carbs but then you'd have the same emissions problems that carbs have (not to mention slaughtering any catalytic converter you have fitted). they can also ice up, they can never be as precise at fuelling as EFI so less mpg, poor hot starts in hot weather because the fuel boils, and the venturi effect required to draw fuel reduces the max power as it restricts airflow.

that said, carbs will be lighter, cheaper and easier to understand than the complex mass of wires in and EFI box, but i reckon EFI gets a bad reputation not because of any inherent problems, but simply because it's usually badly implemented, giving an easier job during emissions testing, but giving the rider a hard time.

perhaps this is one of those "old school / new skool" things

Emmission regulations - so a they makka my a bike a jerky

I very puzzle with you for sure. You passa your a test a few months ago anda already you expert ona every subject. howa many bikes you ride since you a passa your test? Howa many carby bikes you a ride?

For sure I thinka you spenda too mucha google time

Originally Posted by northwind

K2s have that as well, and it's retrofittable... Not that it's worth retrofitting for such basic adjustment, it's only preload.

Yep, my '02 has that. Makes no real difference. The only way of sorting the front end is to change the springs and oil or GSXR forks.

Originally Posted by Keith1983

I have recently changed from a curvy to a pointy. And to be perfectly honest, if you are simply looking at it from a riding point of view without all the technical stuff I would say the pointy injected one is much the better, !

why?

[the_lone_wolf]

Originally Posted by The Doctor

Emmission regulations - so a they makka my a bike a jerky

ok, i'll bite...

yes, emissions regs. in order to make it easier to pass them manufacturers will shut off fuelling completely whilst the throttle is closed at an engine speed other than idle, unlike a carb that always allows some fuel to seep into the engine. when you open the throttle the transition from no fuel to fuel is where FI trips up, too much and you get a jerky response, too little and you don't get a sharp enough response. a carb already has some fuel going to the engine so you don't get the same on/off response... perhaps if you know of a reason why that isn't correct you can let me know?

as for my recent test pass yes, i've only had a piece of paper saying i've jumped through the hoops to ride on the road for a couple of months, does that also mean that i couldn't have been interested in bikes and anything else with a motor for years previously? perhaps i just didn't have the time and/or money to take up riding then and i do now? perhaps you should think before jumping to conclusions about someone

and lastly, don't you think it's a little childish to hide behind an pseudonym and follow people around an online forum trying to illicit a response

[northwind]

Originally Posted by yorkie_chris

And northwind (Andy?) while you're here...

After putting a Fuel SS oval can on I seem to have a flat spot at about 4500rpm, shows itself as a hesitation when accelerating at WOT.

I'm thinking shim the needles a bit?

Chris

Sorry mate, I missed this. A shim or even a whole step up the needle'd probably fix it (UK svs have slotted needles so you can just move the jesus clip, though that's a big jump), but it could be the mains starving the needle. It's a wee bit far down for that though Try something for me, stick it in 2nd or third, ride along at 5-6000rpm, and bang the throttle right open, see what it does. I think it might have a stumble before it drives, and if it does, that's a nice symptom for undersized mains, since that's where the cross- influence is. It's not foolproof but it's a handy trick.

[northwind]

Originally Posted by the_lone_wolf

the only reason poorly implemented EFI is jerky is because of emissions regs, you could program the black box to provide exactly the same fuelling as carbs but then you'd have the same emissions problems that carbs have (not to mention slaughtering any catalytic converter you have fitted). they can also ice up, they can never be as precise at fuelling as EFI so less mpg, poor hot starts in hot weather because the fuel boils, and the venturi effect required to draw fuel reduces the max power as it restricts airflow.

This is all completely true But, unfortunately, we live in the real world where FI is fitted to most bikes for emissions control and for satisfying fashion, and usability is a distant third. By the time FI became mass market, carbs were very evolved and very effective, while at the moment FI for mass produced bikes is still coming forwards in leaps and bounds... But a lot of peple ride one bike with bad FI and decide that the whole idea's stupid (edit) and then again others know that FI should be better than carbs, and assume that therefore all FI is better than all carbs)

Originally Posted by the_lone_wolf

ok, i'll bite...

yes, emissions regs. in order to make it easier to pass them manufacturers will shut off fuelling completely whilst the throttle is closed at an engine speed other than idle, unlike a carb that always allows some fuel to seep into the engine. when you open the throttle the transition from no fuel to fuel is where FI trips up, too much and you get a jerky response, too little and you don't get a sharp enough response. a carb already has some fuel going to the engine so you don't get the same on/off response... perhaps if you know of a reason why that isn't correct you can let me know?

as for my recent test pass yes, i've only had a piece of paper saying i've jumped through the hoops to ride on the road for a couple of months, does that also mean that i couldn't have been interested in bikes and anything else with a motor for years previously? perhaps i just didn't have the time and/or money to take up riding then and i do now? perhaps you should think before jumping to conclusions about someone

and lastly, don't you think it's a little childish to hide behind an pseudonym and follow people around an online forum trying to illicit a response

I think its due to emmision regs too. I was talking to a guy with an FI fireblade the other day, he finds his bike jerky at low rpm. Such annoyances can be sorted with a "power commander" or similar electronic/software modification, removing that jerkyness. I'm sure honda could, if they wanted, make the EFI super smooth - but at the expense of flouting emissions laws.

And to stick up for lone wolf...i've only had my liscence a year - but i've been reading the appropriate motorcycling literature since i was 8 years old. You pick up alot, and notice things from whats written in the mags...

Matt

[yorkie_chris]

Originally Posted by northwind

Sorry mate, I missed this. A shim or even a whole step up the needle'd probably fix it (UK svs have slotted needles so you can just move the jesus clip, though that's a big jump), but it could be the mains starving the needle. It's a wee bit far down for that though Try something for me, stick it in 2nd or third, ride along at 5-6000rpm, and bang the throttle right open, see what it does. I think it might have a stumble before it drives, and if it does, that's a nice symptom for undersized mains, since that's where the cross- influence is. It's not foolproof but it's a handy trick.

Ok will give it a go, offhand I don't think it does but will check tomorrow, also remember the 33hp kit, I believe this doesnt let the slides open all the way, hence why I reckon its the needles need raising a little.

Chris