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250r update and mods, any other suggestions

4137 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
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Tire Fuel tank Wheel Vehicle Automotive lighting
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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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here's some article on Ari's bike. They managed to shave off 60-lbs!

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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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
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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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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!!!
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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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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Well, between software-download from and hardware from Ali, you may have working solution. I suspect hardware boxes have serial# embedded and free software checks back to mothership to verify serial# is validated. Wouldn't hurt to try.

Problem is, once you've connected to ECU and downloaded factory maps, what are you going to do with it?
How would you know what, where to adjust in which direction???

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YES - I understand that AliExpress kit includes software burned into a CD that matches their kit. Other software will probably not fit into AliExpress hardware.
The problem may be elsewhere, and it's still a problem:
The kit does not include an adapter\connector, for our CBR
Did you scroll to bottom of AlienTech link? There is link to adapter cable.

Can also buy DLC to OBD2 adapter cable. Then KESS attaches to OBD2 connector.
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Are you asking about diagnostic tool or something for tuning/adjusting ECU? They are completely different. For diagnostics, you've done that very well with following procedures in manual. Best tools have been used by good mechanics for 100-years: multimeter, vacuum gauge, fuel-pressure gauge as shown in manual.

For tuning, you have to find dyno shoppe with person who knows how to use the specific tuning tools for your bike. Running dyno and drawing pretty graphs is easy. Modifying bike's OEM maps to improve is much, much more difficult and you must have person that knows the specific tuning software for your specific bike model. In S.F. Bay Area, you can get basic dyno graph for U$150/hr. But to find shop that has competent tuner is U$600/hr.

I gave you link to datalogging tool for tuning in previous posts.

Once you have factory maps downloaded, you can use datalogs for analysis and modify maps with this software TunerPro and TunerPro RT - Professional Automobile Tuning Software
Here's another source for interface hardware and cable:
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