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250r update and mods, any other suggestions

4120 Views 26 Replies 6 Participants Last post by  DannoXYZ
So this is the 2012 I’ve been dumping money into for fun let me know opinions and what else would like to be see done to it “that can’t be done”
Leo Vince lv10 pipe
Tinted windscreen
160 rear tire
13t front sprocket
Thinking about a power commander if anyone has one let me know if any decent results
Feel free to comment, critique, question anything
Tire Fuel tank Wheel Vehicle Automotive lighting
Tire Fuel tank Wheel Vehicle Automotive lighting
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A buddy of mine has a KTM RC390 and did a few mods like removing the catalyst from the stock pipe.

He installed a Power Commander with a map from a company that tunes the RC390 engines, and says it has made a significant difference.

Not sure if the CBR would respond the same way. It depends somewhat on just how good or bad the original mapping is and how good of a tuned map you can get.

We messed around with the PC and a few different maps for my son's R6 at one point, and it's a bit of trial and error getting a good one without doing actual dyno tuning.
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The first thing I did was shorten the side-stand by about 5mm (the angle of the tilt was doubled to 11 degrees, because otherwise the motorcycle has a tendency to falling to the side).
And I took out the catalytic converter which was already pretty clogged.
https://www.cbr250.net...cbr250r-stock-exhaust-inner-diagram...(LINK)
https://youtu.be/Cg9mnmHgd8Y(LINK)
Now I replaced the steering bearings that were need replacing, to reinforced roller bearings. I would have been happy for a higher windshield, + 20cm? but unfortunately I did not find such an upgrade for our model.
How many miles has on your odometer?
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The first thing I did was shorten the side-stand by about 5mm (the angle of the tilt was doubled to 11 degrees, because otherwise the motorcycle has a tendency to falling to the side). And I took out the catalytic converter which was already pretty clogged. Now I replaced the steering bearings that were need replacing, to reinforced roller bearings. I would have been happy for a higher windshield, + 20cm? but unfortunately I did not find such an upgrade for our model.
How many miles has on your odometer?
14000 total but I completely rebuilt the entire world nine at around 12000 and I guess the American versions doesn’t come with a cat this is a straight pipe to the can
The first thing I did was shorten the side-stand by about 5mm (the angle of the tilt was doubled to 11 degrees, because otherwise the motorcycle has a tendency to falling to the side). And I took out the catalytic converter which was already pretty clogged. Now I replaced the steering bearings that were need replacing, to reinforced roller bearings. I would have been happy for a higher windshield, + 20cm? but unfortunately I did not find such an upgrade for our model.
How many miles has on your odometer?
A buddy of mine has a KTM RC390 and did a few mods like removing the catalyst from the stock pipe.

He installed a Power Commander with a map from a company that tunes the RC390 engines, and says it has made a significant difference.

Not sure if the CBR would respond the same way. It depends somewhat on just how good or bad the original mapping is and how good of a tuned map you can get.

We messed around with the PC and a few different maps for my son's R6 at one point, and it's a bit of trial and error getting a good one without doing actual dyno tuning.
i just don’t know how much more power is worth the $400 for the commander but will most likely get it and find out and if you see me selling one on here it’s didn’t do too much lmfao
U.S. version came with cat, someone already replaced it ahead of you.

Personally, I really like lightweight bikes, they handle so awesome in twisties! And on track. So I would do:

  • CF wheels, will hold wider tyres better too for better cornering grip
  • rear fender eliminator with angle-bracket
  • CF bodywork & mirrors
  • clip-ons
  • lightweight rear-sets
  • CF or aluminium tank
  • titanium exhaust
  • titanium axles and hollow-chromoly bolts everywhere possible

You can easily shave off 30-40 lbs and bike will be faster and completely transformed.
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In addition to the above, one of the best and cheapest improvement is a quick turn throttle tube along with new grips. Another cheap but excellent improvement is aftermarket levers. For better braking results and feel, get performance pads as well as a steel braided line for the front wheel. For a bling factor, a shift indicator light is pretty cool, in addition to being actually useful.

Personally, I think keeping the original size tires is better in terms of keeping the CBR250R's excellent handling characteristics.

As for wheels, the original cast wheels are heavy so changing them to CF or forged wheels will definitely make a big weight difference. However, If you seek performance, just get better tires. You'll be surprised how much better tires make in terms of handling. Definitely will give you more cornering confidence.

I've considered installing a power commander or the like same products but just couldn't justify the cost for the CBR. It would be pretty cool if I can install a quickshifter kit along with it, though.
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See if you can find articles by Ari Henning, formerly of Motorcyclist Magazine. He raced a CBR250R for a while, and I believe he modded it along the way. Eventually he came to the conclusion that it was holding him back no matter what he did - which is the truth.

It's a decent cycle, but was not designed as a sport or race bike.

There's only so much you can do.
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See if you can find articles by Ari Henning, formerly of Motorcyclist Magazine. He raced a CBR250R for a while, and I believe he modded it along the way. Eventually he came to the conclusion that it was holding him back no matter what he did - which is the truth.

It's a decent cycle, but was not designed as a sport or race bike.

There's only so much you can do.
Which is why the r1 I got gets the majority of my love lmfao
here's some article on Ari's bike. They managed to shave off 60-lbs!

https://www.motorcyclistonline.com/how-to/2011-honda-cbr250r-doin-time-4/
https://werkstattsf.wordpress.com/2013/07/15/race-report-thunderhill-raceway-willows-ca/

He's 3-4s faster than me on Ninja 250 @ Thunderhill. Wished I started racing earlier, could've learned lots from him! He went on to RC390 and set track-record @ Sears Point Sonoma couple years ago. Until Rocco...
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here's some article on Ari's bike. They managed to shave off 60-lbs!

https://www.motorcyclistonline.com/how-to/2011-honda-cbr250r-doin-time-4/
https://werkstattsf.wordpress.com/2013/07/15/race-report-thunderhill-raceway-willows-ca/

He's 3-4s faster than me on Ninja 250 @ Thunderhill. Wished I started racing earlier, could've learned lots from him! He went on to RC390 and set track-record @ Sears Point Sonoma couple years ago. Until Rocco...
One of the motorcycle engines used is a cbr250r in a grom. I love this guys channel.

This tech is probably the way to go in 2021...or maybe a speeduino. There is more power available with intake, exhaust and ECU. But it's over priced IMO once you add the cost of a powercommander, and speedohealer.
Yeah, I'm big fan of tuning with EFI. Good comparison is U.S. Ninja 250 with carbs vs. EU version of same years with EFI. Using Woolich software to fine-tune EFI to optimise same mods: full exhaust, free-flow intake, EFI gets +12bhp vs. carbs +7bhp.

Any time it's possible, better to reprogram factory maps in ECU rather than using
piggyback.
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Check out Throttle Out, season 1 episode 3. Ari puts Banshee/RZ350 2-stroke engine into R3! Imagine putting 3x power in to CBR with less weight! That's A LOT of fun!


More time spent installing Microsquirt EFI system would've allowed much quicker tuning and less wasted time troubleshooting at track.
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Yeah, I'm big fan of tuning with EFI. Good comparison is U.S. Ninja 250 with carbs vs. EU version of same years with EFI. Using Woolich software to fine-tune EFI to optimise same mods: full exhaust, free-flow intake, EFI gets +12bhp vs. carbs +7bhp.

Any time it's possible, better to reprogram factory maps in ECU rather than using
piggyback.
I would guess that microsquirt/speeduino would be far better than factory ecu remapping, unless you have a ton of free dyno time. Only a full replacement ECU with data logging would let you use a wideband O2. Also could use multiple maps for different riding conditions or fuels. Plus the open source ones all support a quickshifter, or launch control which really seems like fun.

Love the Zach and Ari content, had no idea this show existed.
In end, all that really matters is injection-duration and ignition-timing. If you've got programmable EFI system, whether OEM ECU or aftermarket standalone, results should be similar. Now tuning-software may be much better with aftermarket, so can save you lots of time. But, performance should be similar once you've finalised maps.

I really like this all-digital wideband-O2 with on-board datalogging. No need for datalogging ECU or laptop, data stored in on-board memory for later download and analysis. Can usually get about 10-laps on track in, which is more than enough. Tech Edge - Tech Edge, Home

I like their season-1/episode-2, Junkyard Bikes vs Zombie Apocalypse, was hoping to visit after my move to Mesa, AZ. Unfortunately, place had burned down couple years earlier! Boo!!!
Great video. I learned that at full throttle you're running open loop on a bike, so the wideband O2 sensor isn't going to be as useful as on a car.
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Yes, wideband is critical to optimise mixtures. It is NOT used by ECU to adjust mixtures. But data is analysed by a human who goes in and re-programs ECU for more powerful settings than factory's good-enough compromised settings (for MPG & emissions goals).

Factory ECU under partial throttle uses O2 sensor for feedback and will use data to adjust mixtures to 14:7:1 AFR for best emissions and MPG. This is known as closed loop-operation.

Under WOT, ECU ignores narrowband flip-flop O2 sensor because it can only detect 14.7:1 AFR (open loop operation). Instead, ECU just looks up fixed pre-programmed map using LOADxRPM reference points. These maps are optimised for safe and reliable operations, typically in 11.0-12.0:1 AFR. Carbs are even worse with super-rich 10.0-11.0:1 under WOT.

This is rich setting with extra fuel for safety in case you get bad petrol from station out in boonies, or run WOT on super hot day. Or have failing fuel-pump or clogged injectors. These conditions can cause lean fuel mixtures and result in detonation/pinging, overheating, and blown headgaskets or holes in pistons.

But rich safe mixtures robs lots of HP since max-power is obtained around 13.5:1 AFR (remember that '60 hot-rod saying?). So... the wideband O2-sensor gives you AFR data under WOT open-loop operation so you can optimise mixtures away from factory too-rich settings to more powerful 13.5:1 by re-programming ECU maps.

On Ninja 250FI leaning out WOT mixttures gives a substantial +14% increase in power! Note how inconsistent factory WOT fuel-curve is, it's wavy and all over the place. Adjusting it to most-powerful flat 13.5:1 curve picks up torque & power all across powerband.
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You can't learn about engine-tuning from youtube, it's like trying to learn brain-surgery or building interplanetary rockets. The ones who actually has info you're looking for is too busy working for Formulae-1 or MotoGP teams to be making youtube videos. Some of them write books after their pro-motorsports stint. Here's good list:

Internal Combustion Engine Fundamentals - Heywood 1988 McGraw-Hill
Engineering Fundamentals of Internal Combustion Engine - Pulkrabek 2003 Prentice Hall
Flow and Combustion in Reciprocating Engines - Springer, Arcoumanis, Kaminoto 2009 Verlag Berlin Heideberg
Performance Tuning Theory & Practice - Four Strokes - Bell 1981 Haynes
Tune & Modify Automotive Engine Management Systems - Hartman 2004 MBI Publishing
Four-stroke Performance Tuning Bell 2012 Haynes

If you want on-line reading, check out Megasquirt's guide, very good intro, but should still get those books above to understand background behind why you want all those settings a certain way.

Also on-line courses are good as well. Learn How To Tune Like A Pro | Online Tuning Courses
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Great video. I learned that at full throttle you're running open loop on a bike, so the wideband O2 sensor isn't going to be as useful as on a car.
Yes BUT...Sorry! Maybe you did not really understand the explanation?
The point is:
1. The motorcycle injection sys does not have the same effect it does in cars, because in cars the injection is directly into the combustion chamber, and in motorcycles (because of the high RPM) the injection is into the suction manifold(to the Throttle Body).
2. Since the injection in motorcycles is to the intake manifold(Throttle body), and since the spraying of the fuel in the carburetor is also carried out in the intake manifold, That's why there is a similarity between the two devices in motorcycles: Injection Vs' Carburetor.
Handwriting Rectangle Organism Gesture Font

3. In injection the fuel is flow by the pressure created in the fuel pump.
In carburetor the fuel is flow by vacuum effect (a passive mechanism that works according to Bernoulli's law).
4. The carburetor works in an open control circuit, if there are changes in atmospheric pressure (cold day versus hot day, riding in the mountains, or riding in the valleys ...) then the operation will not be optimal, and sometimes the main jet will need to be replaced.
The injection system(EFI) has a closed control circuit. The amount of fuel is determined by a number of parameters measured by sensors: oxygen, throttle angle, temperature, pressure, and RPM. The data is collected, and is used as a "Map" for all other engines that are mass-produced. The map is burned in the memory of the engine computer(ECU). Original OEM Engine Control Unit (ECU) have no reprogramming capability.
Thanks to the "Map", the engine automatically adjusts itself to a wide range of situations (hot, cold, etc ...)
5. It is not enough to buy a ECU kit that gives you the option to program the map you want preference for:
  • fuel economy,
  • or preference for high power,
  • or preference for high torque,
and you need the expensive equipment that will allow you to do it yourself. So whoever wants it should go to a mechanic who has this specialty and he has the required equipment.
6. So far I have only talked about a change in the computer(ECU), any other change that is made to improving the power, affects the parameters of the amount of fuel and in order to enjoy it to the fullest you need to calibrate the "map"(ECU).
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here's software to re-program factory ECU. Gotta know what you're doing. Very, very easy to blow up engine when straying away from factory settings...

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