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Discussion Starter · #1 ·
i am slowley starting to plan out my next bike (cause i cant just enjoy one once i get it running, i have to buy another broken "project" or-else im bored) and thistime i am looking at somthing newer than my turd of a 20 year old cbr. a gsxr 750 is my first choice at the moment and 99-05 seems like its gonna be around my pricerance so i pretty much get to choose between CFI or Carbs.

the plan is to eventually put the engine in a whole new chopper frame, (sorry guys:fu:) and get as much horsepowere out of it as i can within a reasonable cost.

i had a 05 fuel injected wr250r for a while and it was so nice to start up nomatter how long it had sat or how cold it was but from my understanding that means at minimum i need to buy a powercommander 5 to tune it for all the stupid shiti put on it like straight pipes and stuff.

and all the other PC acessories seem pretty tempting like the exaust sensor that automatically ajusts my air/fuel ratio but is it really gonna be worth the $5-600 more than a carborated bike?



will both the carborated and fuel injected engines put out 135ish horsepower with the same amount of tuning or will the FI version just be a matter of plugging in the power commander?


god, and this is gonna be the easy part of the project, i also have to teach myself how to weld a frame:shootme:

ohwell....
 

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Normally I'd say EFI is a no brainer, but early Suzuki efi was well.....kind of shitty. We had a lot of older gsxr's at the dealership come in for rough idle/stalling, hard hot starting, no start (dead fuel pump, usually after sitting for a couple years), FI lights for the secondary throttles, not the most reliable stuff ever.

Power commanders make tuning the engine stupid easy compared to swapping jets, though ultimately CV carbs can offer just as much power and smoothness with a good setup. For an older EFI gsxr 750 I'm sure there are hundreds of PC maps out there for every possible setup people do to these things. On the other hand, carbs are a lot cheaper to fix when something goes wrong than EFI.
 

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In my limited experience, many CV carbs don't like pods extremely well. Early '80's Honda CV's in particular seem personally offended by them. Otherwise, carbs are simple as hell and nothing to be intimidated by. The whole automotive industry was carbureted until sometime in the late '70's and vehicles weren't sitting dead all over the roads. We got around just fine. Spend maybe $80 to get a decent set of gauges to synch carbs and rock on. Or, if the particular bike you want is fuel infested, rock on with that, too. Really nothing to worry about either way.

However, I can rejet my carbs at home with a couple simple screwdrivers. I can't reprogram an ECM ( or whatever those things are). ;)

Oh, and a fuel pump on a chop? C'mon bro.....
 

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Discussion Starter · #4 ·
im just tryna go as fast as humanley possible as a broke college student. at 6'1" 220lbs of beef i tower over my cbr f2 and for some reason its maxing out at about 110mphs whitch is unacceptable.

i rode my stepdads kz1000 the other day and its a much better size for me but i need about 130hp to be happy.

so a carborated bike will make the 135-140hp that all the guys claim on the gszr forums with just a power commander and some tuning?
 

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im just tryna go as fast as humanley possible as a broke college student. at 6'1" 220lbs of beef i tower over my cbr f2 and for some reason its maxing out at about 110mphs whitch is unacceptable.

i rode my stepdads kz1000 the other day and its a much better size for me but i need about 130hp to be happy.

so a carborated bike will make the 135-140hp that all the guys claim on the gszr forums with just a power commander and some tuning?
Your F2 should also be faster than it is. I was able to get my old FZR600 up to north of 140 when it was stock.
 

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Normally I'd say EFI is a no brainer, but early Suzuki efi was well.....kind of shitty. We had a lot of older gsxr's at the dealership come in for rough idle/stalling, hard hot starting, no start (dead fuel pump, usually after sitting for a couple years), FI lights for the secondary throttles, not the most reliable stuff ever.

Power commanders make tuning the engine stupid easy compared to swapping jets, though ultimately CV carbs can offer just as much power and smoothness with a good setup. For an older EFI gsxr 750 I'm sure there are hundreds of PC maps out there for every possible setup people do to these things. On the other hand, carbs are a lot cheaper to fix when something goes wrong than EFI.
Very well said, probably the simplest answer to a complicated question I've ever heard.

In my limited experience, many CV carbs don't like pods extremely well. Early '80's Honda CV's in particular seem personally offended by them. Otherwise, carbs are simple as hell and nothing to be intimidated by. The whole automotive industry was carbureted until sometime in the late '70's and vehicles weren't sitting dead all over the roads. We got around just fine. Spend maybe $80 to get a decent set of gauges to synch carbs and rock on. Or, if the particular bike you want is fuel infested, rock on with that, too. Really nothing to worry about either way.

However, I can rejet my carbs at home with a couple simple screwdrivers. I can't reprogram an ECM ( or whatever those things are). ;)
Another good point, I own a couple of both and see both sides.

im just tryna go as fast as humanley possible as a broke college student. at 6'1" 220lbs of beef i tower over my cbr f2 and for some reason its maxing out at about 110mphs whitch is unacceptable.

i rode my stepdads kz1000 the other day and its a much better size for me but i need about 130hp to be happy.

so a carborated bike will make the 135-140hp that all the guys claim on the gszr forums with just a power commander and some tuning?
If all you want is straight speed skip the 750s and look for a banged up zx1100, or a gpz 1100. Of course I'd keep it lower than 110 on public roads...

I know a guy that can get 125 rwhp out of a sohc CB750. It's all in how much you want to spend.

The biggest contributors to making horsepower are cc's and airflow through the head. Get a big motor with a great flowing head. The method fuel delivery is secondary.
Well said.


Your F2 should also be faster than it is. I was able to get my old FZR600 up to north of 140 when it was stock.
I have no speedometer on my F2, but with -1 +2 rear sprockets and no fairing I know I wouldn't hit 140, 110 might be the top without modding the engine.
 

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Your F2 should also be faster than it is. I was able to get my old FZR600 up to north of 140 when it was stock.
No shit! Your cbr is broken dude.


Even with -1 +2 gearing it should go way faster than 110.


Jon
 
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