Re: Honda CBR 250R

Hi KP Bro,for me the free flow filter installation was much after fitting a slip-on exhaust so really don't know how it would perform on a stock bike,but in my bike even though the gains with the filter was just marginal the throttle response have become much smoother also no noticeable change in sound and fuel efficiency,if i were you would certainly go for it.

Re: Honda CBR 250R

top speed of cbr 250r ....real top speed

Re: Honda CBR 250R

~150 kmph in favourable conditions.

Re: Honda CBR 250R

Hi Guys I am planning to change my baby's front tire suggestions please, I am gonna do it tommorrow itself please thorow your experiances soon.

Thank you in advance.

For a info rear tire changed 4 months back and that time I was not a member of this so got it changed with Coutigo from Honda showroom. Now that I am in will go by experts.

Re: Honda CBR 250R

135+ with ease...

tugged down.. open road.. pushed hard 149..

less cross wind ... completely tugged... open road and more time.. 153.. max i could ever do...

people claim 160.. i could never manage to do.. either the bike isint performing else i am too heavy..

so as stated keep a figure 150 in mind.. nutin more than that..

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IRC is your best bet..

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not sure of the info you looking for however it is fine until a FFE and a filter. if you plan to use fuel mappings i would request you to stay away. have seen a few rides with busted engines.
India is not yet the place for trying all this stuff . atleast not for CBR 250. and spending quarter amount of the bike itself for marginal gains wont be sensible. CBR runs open loop and hence the fuel mapping is hard coded i assume and wont change with mods you do. it already runs lean.

Re: Honda CBR 250R

Hi I would like to know bit more if you dont mind, I have a plan of travelling to Goa this month and after this mostly I will be a city rider and weekend tourer.

Will be looking for a better grip most important and life(Sport bike cant expect more but ya a bit)

Re: Honda CBR 250R

And Finally, after struggling for days with my ASC(Durga Honda), I came across a better ASC(Utkal Honda). The crazy Vibrations at above 5K rpm was killing me(Not RTR type sporty vibs which I love, rather a certain irritating vibration). Got valve adjustment done(no, not shim issue). Vibs have disappeared totally now. It cost me around 1300/- with front fork oil and seal and adjustment of the bent handlebar and certain rusted nuts and bolts here and their. Gave my bike back after one day only. But, thats it, the showroom didnt even had oil seal in stock, they sourced it from my former svc . Atleast, they have better brains to know the problem.


For people searching in google, for Best Honda Service center in Cuttack - Utkal Honda.

Re: Honda CBR 250R


I am aware of the FFE+Filter part,
I was thinking of getting real time feedback from users who are using the akra slip-ons/slip-on+header combo.
I intent to use the custom tuning box with custom maps(Area-P, as used by our fellow member in ninja 300 thread with a custom maps made as per his riding pattern and climatic conditions of the area) I know it can be a huge investment , coming close to 1lakh or so. But all of this is just a planning stage , a feasibility study is in order ,once i gather all the information required and check if the amount of power or satisfaction can make sense to the cost it might demand.


Cheers
ride Safe
Krishna

Re: Honda CBR 250R

Hi mate,

to the best of my knowledge, Honda CBR 250R has a closed loop system with a narrowband sensor. It becomes Open loop the moment you whack open the throttle and ride really hard at higher revs where the ECU pumps in more fuel for more power. If you go for Slip -on's it will not affect the fuelling of the bike simply because the Slip on is purely for the noise factor. a foam filter in the likes of Pipercross and other foam based filters will allow better breathability in comparison to stock pleated paper filter. Thanks to an intelligent ECU, it can make fuelling adjustments upto 8 - 10% from the original values so a slip - on and a ff air filter will not affect the fuelling much or lean out the fuelling at all as for the extra flow of air, the CBR has a MAF sensor. If you do opt for a full exhaust system from Akra or Yoshi then yes it is beyond the fuelling adjustment level of the stock ECU and custom ECU is needed to compensate for the extra fuelling required.


I suggest that you should start bothering Gopakumar sir on this thread as he has reported some interesting results with his stint with slip on, air filter and head porting on his CBR. A long term report log is pending from his end..


Cheers,

Re: Honda CBR 250R

You're working for Akrapovic or what? Reason is because, this is the same explanation they (Power commander V) told me when I bombarded them with questions & one of them being if PCV will be able to deliver more power with stock exhaust.

BTW, there's a numeric factor associated with "WHACK OPEN", it's above 80% (as told by HMSI & 85% as told by PCV5) of the throttle & then it becomes open loop & FE goes down drastically (which I've checked personally several times) & the max speed without affecting with (means 80% of throttle) the top speed will be 135 on top gear with a FE anywhere between 27 to 30 on long hauls without break & with one full tank capacity.

Re: Honda CBR 250R

Hey, Shiv, was thinking about sending you a PM and now you have replied here..:-D
Yeah, just what i was looking for, I was also under the impression that the slip on won't need any modification in the maps,just wanted to be sure, but this open loop thingy at WOT was something I did not know earlier, and I am already talking to gopakumar about his slip-on, the way i see it, his is the SS version which is more restricted and more heavy too but i was planning for the full carbon fiber version , which is more free flowing and lighter, and more performance gains(nothing that would create a worlds difference)
I had read all the documentation and checked the Dyno chart results on the Akra site for each of the slip-ons.

And the header pipe might come at a later stage, owing to the investment I would have to put in.

Honestly, more than the performance figures gain(I won't be using the bike in such a way to squeeze out every drop pf power) my main aim was to have a unique bike than others, the tri-color already makes things easy(haven't spotted more than one or two of them on road) but still, that itch to make it more personal never goes I guess.

And Shiv, when it comes to custom mapping, I was thinking the one abhimanyu chose is a better option than PCV ? Since he got a totally custom map made from some tuning company right ? based on his riding pattern and location details ? It was Area-P i think, if I am not mistaken ?


True that, during my frequent visits of the Bangalore-Trichur circuit I did maintain about 120ish kmph throughout the KA and TN highways and have got a mileage of above 30 and below 35kmpl

Cheers
Ride Safe
Krishna

Re: Honda CBR 250R

LOL Saar,

Nope... all knowledge gained courtesy: post a wonderful experience with a certain "parts supplier" and me being stuck with a new dilemma of which bike to upgrade to from a 153cc FZ:

* Duke 200/CBR 250R?
* Better cost of ownership?
* which one will offer me more possibilities to mess around with? and then research research and more research..

Please allow me to blabber for a bit...

If one really thrashes his bike and does WOT then the ECU will to go open loop regardless of the rpm. With a narrowband sensor, usually the ECU takes a reading uptil mid range if the throttle is maintained consistently at a certain rpm. It is this time, when the ECU will read and check if the stoichometric ratio has been achieved or not. If not then it will compensate by adding fuel.

Any CBR rider can do this experiment, Take out the battery terminals which connects to the ECU, wait for 20 mins and then reconnect the ECU back to it. If you start riding then, you may notice that the grunt factor has gone down severely. Reason being: the stock ECU by nature will revert back to factory settings the moment there is a power loss and will need a certain no. of kms to re-learn the parameters of the place you are riding in which may include: MAF reading, temperature and moisture, then slowly will make adjustments to achieve the best fuelling ratio possible. After say 5 kms the bike will be back on making power..

Compared to an open loop ECU and closed loop ECU requires much more processing power as it has to calculate lot of variables based on the readings it gets from different sensors hence, more costly..

Saar based on what i have learnt post my experience with Hot Roding: simply by adding an ECU like Power Commander V will give you slightly more grunt factor at the cost of Fuel economy. The second biggest problem these ECUs have even with the autotune feature (optional) is that they will need a dyno where one can whack open the throttle really hard and keep it at redline on every gear so that the ECU learns the parameters.. If the ambient temperature and other natural parameters change, they will need a visit to such station all over again.. good for a race track not good for a daily street ride.

Then just with plonking an ECU the gains will be very minute as the basics of engine tuning suggests: being an "air pump" if you make changes in the intake, you will also have to make changes with the exhaust to keep the intake and exhaust flow of gasses as smooth as possible. I doubt how many people have access to a dyno or a road roller... nor we have roads safe enough to do the same without breaking speed limit or without putting ourselves at risk if someone does attempts this on public roads.

In order to make everything work the input costs then shoot sky high with a performance air filter+FF exhaust + ECU.

If one is still hungry for more power but without investing too much and fiddling with the stock ECU then the alternate way will be going for gas flow porting/head porting and slightly tweaked slip on exhaust... that's about it!! With gas flow porting, the only thing one doing is increasing the volumetric efficiency of the bone stock engine which may result in stronger low end grunt and linear power band.

Gopakumar sir & FZERIDER are one of the only few people i know of who have gone for such a route as an experiment. So without long term test reports i would neither recommend nor jump to conclusion, singing all praises too quickly..


Cheers,

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I believe what you are talking about is the piggyback ECU sold and mapped by Fuelmoto with a possible lifetime support from them for fuel maps. I don't think Area-P manufactures or maps ECU for CBR as they only develop kits for Ninja. I guess you will have to check with Fuelmoto USA on the same and see if they do provide you custom maps based on the climate, temperature and the area you reside in.

If you do end up taking a full exhaust system with custom pipes and header at a later stage, you will have to get hold of an aftermarket ECU as the stock ECU simply cannot make fuelling adjustments nor was ever designed to handle such parameters from the factory. Your CBR will be then potentially running leaner and may damage the vehicle in the long run.

If all that you are looking for is just visual aesthetics, then going going for a Slip-on exhaust will not give you any trouble. If you are indeed looking at more power then you will have to tweak or stock exhaust pipe connecting to the slip-on along with gas flow porting for more volumetric efficiency and that will be it. After what i have experienced i will never ever recommend going anyone for a BB kit or any such nonsense. Stock CBR has a NiCaSil coated cylinder to ensure a well built and resilient engine. I would not want anyone else to mess around with that!

Hope this helps...


Cheers,

Re: Honda CBR 250R

Damn, so basically the ECU learns the riders riding pattern and adjusts the fueling in the precise manner ? So , do help me out here, Suppose i travel to a completely different environment than the bike is usually used to running, so will the ECU re-learn the parameters when it detects a change ? I mean, are there sensors for that , which evaluates the Temperature and moisture conditions and all ?

The cost of having to setup a tweaked bike is really staggering, and not to mention lack of technical equipment for it makes it even a worse of a gamble.



Oh, yeah..!!! Looks like I should have read abhimanyu's posts one more time , so Area P is strictly exclusive to Ninja's ,eh ? Well, like I told, now basically the concentration is on the Slip-on only, which in itself is a huge investment for me, and It is not that I am bored of the power of the CBR, it is quite conveniently sedate enough to run around happpily...!! :-D
I do have a 390 sharing the garage if ever i get bored... ;-)
But possibilities are endless, so in future if I was to go in for a header pipe from akra itself(they do provide SS header pipes for their slip-ons for CBR(costs some 10-12k) then probably I will invest in a Piggyback ECU too, if not area-p then something else, PCV is similar stuff right ? Yoshimura does have a piggyback ecu for their full-system, but then i guess it will work out fine with yoshimura exhausts only maybe.
Also, Fuelmoto does provide custom maps for other bikes right ? Just curious

And no way I will be going for a Big-bore. And as far as porting is concerned, I would like to keep the engine block bone stock as far as I can.

P.s: Just the links to the items I have been thinking of :

1) Akra Carbon fiber slip on CBR 250:

Akrapovi?

2)Akra optional header pipes for CBR250 :

Akrapovi?





Cheers
Ride Safe
Krishna

Re: Honda CBR 250R

As far as my research goes... Yep!! Predominantly all the closed loop systems with a narrowband O2 sensor are there mainly for fuel efficiency and keeping emission norms in check. So yes, at mid range with steady rpms, the ECU checks from time to time and make adjustments whenever needed. But that doesn't mean that it will try and learn everytime you start the bike. Once it learns the parameters based on your riding habits, temperature, levity and other factors it will usually keep those values running until during one of the random checks it detects an anomaly.

Say in one of your journeys, if you do take it to a high altitude location like Leh and then witness problems with the power going down slightly, take out the terminals, wait for a bit and the put it back in.. after some time the power band will be back. Basically the residual parameters learned from the plains are wiped out and the ECU does a fresh start learning new parameters all over again. But taking such a drastic step is usually not required unless the symptoms show up.

Fuelmoto USA: Motorcycle EFI Tuning, Exhaust Components & Performance Components - Fuel Moto also sells PCV from their website but i am not sure whether they do provide custom maps and lifetime support on the same for a CBR 250R. You can shoot a mail to them and check with them to clear things out.

Instead of spending so much on a full exhaust system (stage wise) + ECU, for volumetric efficiency without losing on stock bike's reliability you may look at gas flow porting where only the flow rate of the intake and exhaust ports are increased and no other changes are made to the engine. You may notice a significant change in the powerband of your stock bike without losing on FE.

I would still suggest interact with the users who have gone for this route and have clocked significant no. of kms: they will be in a better position to give you an idea about the same.

I believe in long term test reports and would encourage everyone question things before investing.. A very wise step from your end mate

Cheers,

Re: Honda CBR 250R

a short video of my trip to hamsaladeevi. could not get much footage as it was unplanned.