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Apparently Honda in Thailand is suggesting that there will be upgradeable fuel maps sold (and serviced) by Honda for the CBR250R in the future so you can customize the fuel delivery of the bike. Is this what you mean by "upgraded powerbands"?

Mike
 

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Its not an actually part. She is talking about getting more Hp across the power band through exhaust ecu and other engine mods vs keeping it stock.
 

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Could of Specified what she meant by power band... by ie do you guys plan to upgrade the power-band of your bike and and etc. but for now not much after market support is here just yet.
 

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Yes.

The engine is choked up due to emission restrictions. In stock it's only producing far less than it should.

Free it up and let the engine perform like it's designed to.

Free breathing pipe and airfilter to get rid of all that emission restrictive nonsense that is choking it up, then adjust the FI to keep the compression ratio (10.7:1) as it is.

This will have a big affect on HP and performance, and also affect the fuel economy, so it mightn't be for the cheapies out there. :D
 

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when my wife went on her first ride the first thing she said to me was " I had a little hiccup with the throttle. I want you to do the same thing you did to your bikes. You know, the pipe and the chip thing." So yeah, we'll be looking at smog delete, pipe, and power commander when/if they come out. If I can get her to stay off the bike long enough for me to work on it. :) So far since she's gotten her CBR she's commandeered two of my jackets, my good BMW gloves and needed a new backpack. Life is good!!
 

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Free breathing pipe and airfilter to get rid of all that emission restrictive nonsense that is choking it up, then adjust the FI to keep the compression ratio (10.7:1) as it is.
I think you mean to change the Air/Fuel ratio. Most of the bikes run really lean so the tuners enrich the mixture to increase power and combustion stability. Compression ratio is a mechanical ratio that is unaffected by the EFI system and requires major surgery to change. The optimum A/F ratio seems to be around 13:1. Most bikes run~ 15:1 or higher.
 

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when my wife went on her first ride the first thing she said to me was " I had a little hiccup with the throttle. I want you to do the same thing you did to your bikes. You know, the pipe and the chip thing." So yeah, we'll be looking at smog delete, pipe, and power commander when/if they come out. If I can get her to stay off the bike long enough for me to work on it. :) So far since she's gotten her CBR she's commandeered two of my jackets, my good BMW gloves and needed a new backpack. Life is good!!


Lol! "Happy wife = happy life!"
 

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come on........ seriously????
This is how we tune our sportbikes. Redline had it right (with a small error). In a nutshell, think of an engine as an air pump. Freeing up the intake and exhaust allows more air in and out of the motor. More air allows more fuel which gives more power. But if you increase the amount of air without adding more fuel the mixture goes lean which makes it less reliable on ignition and it burns slower so it winds up burning in the exhaust where it doesn't produce engine power and creates other problems. Add to that the fact that the motor is "inhaling and exhaling" 100 times per second and you can see how ignition can become unstable. Enriching the mixture enhances that ignition process and thus low speed drivability and top end power. The reason for the manufacturer's state of tune has to do with the balancing act of emissions, the catalytic converter and the tradeoff between burning the hydrocarbons and producing NOx. Its easy to build a motor that burns off the hydrocarbons but the resulting temp and pressure creates more NOx so they reduce the temp and pressure by lowering the compression ratio and often recirculating exhaust gasses. But this reduces engine power and performance and mpg too. There's a lot of information out there on this but it takes a while to wade through.
 

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Where are you located? I need to find someone to tune my sportsbike. One of my bros reckons NOx is like NOS but faster. Do you know how to fit more NOx to the CBRs?
NOx (oxides of nitrogen) is a generic term used to describe the by-products of Nitrogen and Oxygen as they combine in an internal combustion engine. NOS is used to describe the automotive use of Nitrous Oxide, or NO2. Basically its laughing gas, like you'd get at the dentist. Early in the combustion process the nitrogen and oxygen separate generating free oxygen for more fuel to combine with. Bigger bang. There may be another brand name for nitrous oxide but I am not familiar with it. In Northern California there are a number of dyno tuners, Chandelle Motorsports (Mike Canfield) and Factory Pro (Marc Salvisberg) and Dan Kyle are the only ones I have experience with and would recommend but there are others that are very good. You didn't mention what kind of sportbike you have but unless you are drag racing at a very high level there is no real need for Nitrous as it is only really usable at full throttle otherwise you can burn up your motor. Consider that Ricky Gadson can run a lowered but bone stock Kawi ZX-14 down the quarter mile in 9.2sec and to run that bike at a sanctioned event I believe you need a pro license because it is so quick. I've also seen reports of stock liter bikes getting into the nines.
 

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successful trolls are successful...

come on guys, some of you are rattling on like you have been around bikes and engines for a while and none of you have picked up on the old "4T powerband" gag?

they are taking the piss and you are buying it hook line and sinker. what's next, someone asking for a let handed metric screwdriver?

PLEASE NOTE: i am fully aware that ALL engines have a range of rpm in which they make their maximum power/torque but the term "powerband" is specifically meant for 2T and Diesel engines which make all of their power in a very very specific and small range of RPM.
 

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successful trolls are successful...

come on guys, some of you are rattling on like you have been around bikes and engines for a while and none of you have picked up on the old "4T powerband" gag?

they are taking the piss and you are buying it hook line and sinker. what's next, someone asking for a let handed metric screwdriver?

PLEASE NOTE: i am fully aware that ALL engines have a range of rpm in which they make their maximum power/torque but the term "powerband" is specifically meant for 2T and Diesel engines which make all of their power in a very very specific and small range of RPM.
Please forgive me for not realizing that you are just a snarky little troll. Go back to the third world country you came from and leave the adults alone.
 

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Do you know anythin bout turbos cause i have a project in the works

The real problem with turbos on motorcycles is the powerband is too unpredictable unless its only used for drag racing or LSR runs. If you're leaned over and the power comes on you wind up on the ground. For this bike in particular the size of the housing is critical because the single cylinder only pulses once for every two crank rotations as opposed to a 4 cylinder which has 4 pulses for every 2 crank rotations. You could probably remap the EFI system ( alot of effort on a dyno) but it wouldn't reliably give you the right amount of fuel because it uses an alpha-N system that guesses the amount of fuel needed from several sensors. A turbos' positive pressure would probably read out of range for the airbox value and the EFI system might not keep up with the turbo resulting in a very lean condition pretty quickly. A mass airflow sensor or carburetor would be better. Even with all that effort you probably wouldn't get any more power than a good 450 dirtbike engine which would probably be cheaper to do and more reliable.
 

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rofl...

im not trolling at all. i just cannot believe that noone on here picked up on the obvious troll of the OP...

if you check all my posts i am merely clearing things up that everyone seems to naively scroll past at their own expense...
 

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rofl...

im not trolling at all. i just cannot believe that noone on here picked up on the obvious troll of the OP...

if you check all my posts i am merely clearing things up that everyone seems to naively scroll past at their own expense...
Your very first post detailed all the "deficiencies" of the new 250R vs. the old 250RR when in fact they are designed for different market segments. We all understand that here. You are assuming that the OP is trolling when it's very possible and more likely they just want information. We have a lot of new riders on this forum that don't have a lot of practical experience and just want good information about what to do and what not to do. For you to come along and tell us we don't know anything about motors is, well, trolling. Especially when your experience is based on an ancient bike that needs to rev to 15,000 to make 45hp through a set of outdated wheezy carburetors.
 
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