Re: The story so far.. My Honda CBR 250R

Another quality update.
Can you please let me know the rubbing compounds used? My white Karizma is turning way too yellow for my liking.

Re: The story so far.. My Honda CBR 250R

I am not sure mate. I believe [MENTION=52772]AK3D[/MENTION] will be the right person to comment about it.

Cheers,

Re: The story so far.. My Honda CBR 250R

To remove iron contents, this is the best in the industry & you can get this from Ultimate Detailerz at C.V.Raman Nagar


But then pls remember, metal turning yellow & plastic turning yellow/white are 2 different things & for each of them, the products are different. The above product is ONLY for removing the iron sediments from any surface.

Re: The story so far.. My Honda CBR 250R

Guys i have a doubt... Will abs work if we happen to lock both wheels at the same time?? ( not possible in india atleast.. But in snow or ice i guess its possible ). Because abs works by detecting difference in wheel speed ( front and rear ) and theoretically if you lock both at same time, speed will be 0 kmph and abs should turn off since it thinks vehicle is stationary.. Am i correct?

Re: The story so far.. My Honda CBR 250R


ABS comes into action as soon as it detects a possible wheel lockup while braking... front or rear.. or both at the same time.. it doesn't matter.

Re: The story so far.. My Honda CBR 250R

If abs detects lockup of both wheels at the same time, then it must come in to action when you are standing still.. Thats why abs gets activated only after 10kmph ( dunno exact numbers )

Re: The story so far.. My Honda CBR 250R


ABS is in action at all times when the wheel is in motion.. not when the motorcycle is standing still!

ABS detects possible wheel lockup (resulting in a skid) with respect to the wheels' traction with the pavement (tarmac, gravel, wet surface etc..). That's why ABS won't work even if the wheel is in motion but is in the air! The speed of either wheels doesn't matter at all. The reason why ABS "appears" to be inactive at very low speeds of like 10kph is simply because these speeds aren't fast enough in maximum conditions to lock the wheel that might result in a skid. So while ABS is working to detect wheel lockup under braking at all times (when the motorcycle is moving), it will only work when the wheel would actually lock be it the rear wheel or the front. Rest assured, if you are on a surface which is terrible enough to lock your motorcycle's wheels (front or rear or both at the same) at 10kph, then the ABS will come into action and prevent it.

PS: Do not mix wheel lockup and motorcycle being still. Wheel lockup only refers to when the wheel loses speeds almost instantly (like in fractions of seconds) and becomes stationary due to the typical use of brakes or by engine braking.

Re: The story so far.. My Honda CBR 250R

I guess you didnt get my point... When both wheels lock up at the same time, there is no way abs can detect whether vehicle is moving or not. Both the speed sensors in wheels will return 0 and Abs wont come in to action because theoretically it doesnt have to, when both the speed sensors return 0. Hope you get my point.. And its made to work above 10kmph for different reason. Lets take an example. Say you are stopping at a signal in a slope. If abs is made to work at 0 kmph, when you hold the brake to stop the vehicle from going back in slope. It will keep on pulsating, because according to it, wheel is locked up. This is the reason abs gets enabled only when you move. Atleast this is what i have been thinking all these days.. Correct me if am wrong.

Re: The story so far.. My Honda CBR 250R


Of course ABS works when the wheels are in motion. That's what I said as well. If you read again the situation I explained above, probably you will understand. Let me say it again - ABS detects wheel lockup under braking with respect to the wheels' traction with the pavement. The speed of the wheel doesn't matter here. Taking your example, at 0kph, ABS will of course won't work because at 0kph the wheel is not even in motion.

The reason I say that the speeds (not 0kph) doesn't matter is because ABS's job is to prevent wheel lockup under braking. For example, if you are on a perfect tarmac and riding at 10kph then in all likeliness your motorcycle tyres are getting the best possible grip and traction at that particular speed from the surface. In that case, braking hard at 10kph on an almost perfect tarmac will possibly not result in wheel lockup. Hence, in that particular situation ABS will not have to intervene because the vehicle will nicely come to a halt without skidding (due to wheel lockup). BUT. If you are riding in the rain at 10kph on the same surface including some gravel, then there's a chance that if you'll brake hard then the wheel might lockup even at a low speed of 10kph resulting in a skid. In this particular case, the ABS will intervene and prevent the wheel lockup. So that is why ABS will or will not work at low speeds like 10kph. It all depends how much grip/traction your wheel is getting from the pavement under braking at a particular instance.

A good ABS system will never intervene unnecessarily even when braking at high speeds unless there's a chance of a wheel getting locked. Lastly, for all the above reasons explained above, ABS can work on both wheels at the same time under braking depending on the situation. ABS works independently at either wheels, it's only job is to prevent wheel lockup. Front or rear or both doesn't matter.

Re: The story so far.. My Honda CBR 250R

There is nothing like abs works after after certain speed, when you start your bike and ride it till it reaches 10k phone, the abs module will be doing its checks. So don't mistake it to be working only after certain speed. For answering your question about both wheel locking up, when you jam both the brake levers the bike speed is instantly reduced, this makes the abs to pulsate(the module pumps your brakes for you ). Hope it clears.

Re: The story so far.. My Honda CBR 250R

It is an edge case scenario (IT terminology [emoji3] )

As far as my understanding goes, either of the two will happen:
1. As explained by you, ABS detects speed as 0 and allows the wheels to lock and slip for a minute instantaneous in time. Then (since the calibration is really fine and at a minute level), it would detect a difference in speed after a few milli seconds and come into action. You'd have to be lucky to not fall in those milli seconds.
2. Both sensors detect an impending doom and modulate the pressure to a pre defined max threshold and distribute the braking across both wheels as and when one stops hitting the locking threshold.

ABS are evolutionary systems. They only get more sophisticated with age.

Re: The story so far.. My Honda CBR 250R

There seems to be a lot of confusion on ABS here. No ABS will work at less than a pre-determined speed set by manufacturer....for instance in a car with 4 wheel independent ABS sense and braking, the ABS Will not work at creep speeds . I had experienced the same in the Toyota Camry..

The Thread is about CBR250R and it's C-ABS, so let us keep the discussion relevant to the thread .

Re: The story so far.. My Honda CBR 250R

Thank you PSRji.

We really welcome everyone's inputs and queries and we hope for more interaction from everyone! However, let's keep the discussion to Honda's vehicle and technology for clarity in this thread

I'll elaborate on the C-ABS with some links.
In a nutshell -
The C-ABS on the Honda CBR250R is a combined ABS system. The way it works is that once you reach a speed of over 10KMPH, it'll engage. When you squeeze the front lever, only the front brake will engage, till the point of locking up, where the ABS will kick in and start modulating the brake pressure. When you press the rear brake pedal, the ABS will engage when the point of lock-up is reached, where the sensor will do it's job and also engage the valve for the front caliper pot. The best method is to use both brakes (as is usual with most bikes).

Explanations about Honda's ABS systems.
Honda Worldwide | Motorcycle Picture Book | Electronically Controlled Combined ABS
Honda Worldwide | Technology Close-up
Honda Combined ABS System - webBikeWorld
Honda's Combined ABS - ThrottleQuest







Also note the 300R (and 2015 CBR250R - dual headlamp) does not have C-ABS but a normal ABS system from Honda. The caliper is 2 pot rather than the 3 pot as in the older CBR250R.

Re: The story so far.. My Honda CBR 250R

Hi All,

would like thank the readers for taking an active participation. We all encourage interesting questions, debates and discussion on this thread. I would also would like to thank all the senior members for anwsering the queries in the simplest yet poilte manner, keeping the decorum of the forum to its highest standards... You all deserve a big appreciation.

I hope All queries related to combined-ABS have been resolved after [MENTION=52772]AK3D[/MENTION] 's simple yet elaborative post eh?

QUICK UPDATE:

Moving on, would just like to share a quick update on my CBR. I have so far completed an ownership of 1 month, where i have managed to cover only a meagre 880 kms on the ODO. In this little time, as i slowly took my CBR through the recovery phase in bits and pieces, I must admit: she is growing on me and i am getting to know her better. So slowly, a relationship is developing, a connection, a bond is taking place as rightly predicted by [MENTION=32286]psr[/MENTION] sir & [MENTION=52772]AK3D[/MENTION] many eons ago...

The journey so far has been really joyful yet a big learning curve for me. I have absolutely no regrets in getting hold of this vehicle, even though she came with a few niggles. . I hope to learn more about the vehicle as i continue the journey of understanding my new possession and also in the due process hope to share something interesting and useful with the readers on this thread.

As promised earlier, i would like to share the the condition of the engine oil in the picture below. As the readers will observe, it has darkened further in a very short duration which is a clear indication that the previous oil changes were not followed as per the recommended schedule by the earlier owner.



Pic 1: Condition of the engine oil post 880 kms. very dark amber colour indicating a high amount of suspended particles in the engine oil most likely flushed out by Shell Ultra FS oil.

As the results above may suggest, the superior Shell Advanced Ultra 10W 40 FS oil is busy cleaning out quite a lot of dirt and varnish that may have built up inside the crevices of the engine in the last 20,000 kms. The engine has slowly become butter smooth and she is very responsive to my inputs. Though post 6,000 rpm i am noticing a bit of vibration creeping in on the handle bars. I believe with a good dose of the upcoming Shell Rimula R4 HDEO oil treatment, the engine will be cleaned off gunk and dirt further and with a good layer of ZDDP building up, it will make things even more smoother. I am surprised that even after such a rough treatment received from the previous owner, there is absolutely no shim, valve, cam timing chain or any kind of noise emanating from the engine bay! End of the day i have realised one thing, a Honda is a Honda! Overengineered and extremely robust...

Regardless, I will continue monitoring the engine oil and may do an early drain at either 1,500 - 2,000 kms based on the feedback i receive from the engine. As [MENTION=26077]abhimanyu31[/MENTION] always used to tell me, "your bike speaks to you, you just have to understand what she is telling you"... I will never forget this Yoda gyan imparted by this gentlemen and so far, every step that i have taken, has been based on observation, understanding & feedback i have received from my CBR. So dear readers, start listening to what your respective bikes are trying to tell you.. Believe me, you will learn a great deal more if you pay enough attention to the signs, vibrations, engine note etc. When you understand the language of your motorcycle.. you truly become one!

OK all good ... par... KITNA DETI HAIN? (How much FE??)

I did an unofficial FE run and keeping things on the conservative side, she is now returning a healthy 32-33 kmpl which is astonishing, considering the fact that i have mostly ridden my CBR in 1st, 2nd & 3rd gear during the last 880 kms and that too inside the town. When the owner was selling this 250cc motorcycle: he mentioned that he never managed to secure more than 22 - 24 kmpl in the city and on highways was getting about 33 -35 kmpl. If one looks at the series of simple maintenance and parts replacements that has been carried out so far, the FE has jumped from the earlier quoted figure by an unbelievable 8 - 10+ kmpl. I am yet to test the highway FE nos. but i am pretty confident that it can easily achieve about 40 - 44 kmpl @80 kmph [MENTION=58089]6th Gear[/MENTION] while lazily humming at about 5,000 rpm. So a simple maths of 40 kmpl X 10 ltrs (keeping the rest 2.5 - 3 ltrs as reserve to keep the fuel pump submerged) = we are looking at a tank range of near about 400 kms!! So periodic maintenance is one of the key factors which will enable any rider to get the best of both worlds from his/her noble steed: rideability & reliability.

If i do a comparo with my earlier FZ, the bone stock 153cc motor would slowly start losing its breath @ 80 - 85 kmph and the power band will taper off right after that, not to forget the engine literally screaming at close to 8,000 rpm. So when compared to the earlier experience of owning a 150cc engine, one can imagine the feeling of sheer happiness i am currently going through: where i can easily get good FE (almost equivalent of an FZ), good tank range and enough reserve power in hand to take on any vehicle on the road. So even though for some this may be a premium motocycle, it is still able to keep the "Kitna Deti hain?" junta quite happy. For me a 250cc, 26 bhp motor giving such FE figures along with the capability to do 120-130+ kmph all day long is definitely the ideal one for me. Does whatever i want without shouting out loud..

I know this is a very short post, but please do pardon the pun: office calls, what a spoiler! There are tons of topic to be covered... but will do so in the upcoming posts. Till then, stay tuned!


Cheers,

Re: The story so far.. My Honda CBR 250R

Hi all,

after 2 days of intense rains here, the roads here have become more or less a small pool of water and mud. Keeping in mind the horrible road conditions, i have no choice but keep motorcycling on stand by. Regardless, i finally managed to get hold of a new toy which will help me in keeping my vehicle healthy and ever responsive to throttle inputs. Dear readers, i present before you carburettor cleaning spray from Tribocor.



Pic 1: Tribocor carburettor cleaning spray. Can be used for cleaning EFI throttlebody too.

I am sure a lot of members are already wondering what does a carburettor cleaner spray got anything to do with a fuel injected 4 stroke motor right? Well the whole deal is with the upkeep and maintenance of the Electronic throttlebody. For those members who have no idea where to locate the throttlebody on a CBR, what does it look like, i hope the reference pics below will give you some idea:







Pic 2, 3 & 4: The images above show what a throttlebody of a Honda CBR 250R looks like and where exactly is it located.

If you ever look at any new throttle body/brand new carburettor and use a flash light from the other side and light it up, you will always notice that some amount of light is able to pass through right at the bottom of the butterfly valve. This has been intentionally designed by the OEM manufacturer so that during the time when the engine is starting up or idling, the butterfly valve is kept slight open thus, adequate amount of air:fuel mixture can pass through to keep the engine running.

On any 4 stroke internal combustion engine, due to valve overlapping, (refer to this post from Powerhouse FZ18 thread: http://www.xbhp.com/talkies/general-...ml#post1028831) some amount of ignited flame always manages to escape through the partially opened intake valve and burn off any remaining AF mixture that may be present in between the throttlebody and the valve area. As a result, the unburnt soot slowly cools off and then starts depositing in the coolest part of the area which is on the butterfly valve or at the bottom edge of it. In order to understand why does this happen let us do this simple experiment:

* Take some petrol and then put two, three drops of it on your palm.
* You will then immediately notice a cool feeling in your palm. This happens because the petrol evaporates immediately by absorbing the heat from the exposed part of your hand.

Now Imagine the same thing happening near the throttle body, where some amount of burnt off soot meets the cooled surface of the butterfly valve and also at the bottom where cool AFR mixture is rushing in. It slowly condenses and settles down over there. When the deposition builds up too much, the engine is not able to get correct amount of AFR during idling and at low throttle opening positions. As a result, one may face sluggish performance, engine shutting off for no reason, or even reduced power at lower RPMs. The key is to ensure that the deposits on the throttlebody are cleaned properly at periodic intervals so that the engine gets the right amount of fuel and air mixture when the engine is idling.

I am sure all this text is becoming too much for the readers and the noobs so let me try and break it down into layman language, a simple yet informational video about the importance of throttlebody cleaning (please ignore the product placements):



I hope the video above should give fellow riders some perspective that this phenomenon is universal on any 4 stroke motor be it carburetted or fuel injected. As per my discussion with the senior riders, the recommended periodic cleaning interval for throttlebody/carburettors should be done anywhere @ 25,000 - 30,000 kms. Once, the throttlebody is cleaned properly, then the immediate after effect: one may notice in his/her respective motorcycle:

* Instant start-ups
* Steady engine idling
* Better engine response @ lower RPMs
* No engine stalling when throttle is shut off by the rider

I must point this out that usually, throttlebody cleaning is not mentioned anywhere in the workshop manual or in the standard manual received along with the bikes. I have never seen any such information even in the manuals of my previous motorcycle: Yamaha FZ. But it works!!! Though we are strictly a two wheeler forum, for the sake of an example let me share an incident: My 11 year old, 1,27,000 kms family ford ikon was slowly becoming very lazy, the moment the AC was turned on. During, early morning starts, the engine would suddenly die or the engine rpms would be dancing constantly. Where earlier on speed breakers we could easily manage to go over it on 2nd or 3rd gear, now the vehicle could only manage to do it when the gear was changed to 1st. So the tell tale signs gave us a pretty clear idea that something was not right. Frustrated, my father was almost getting ready to sell off this car. I then spoke to senior rider @psr ji and wanted his advice what could be the possible reason behind this sudden weird behaviour from the vehicle. He then immediately asked me this question: when was the last time the throttlebody was ever cleaned? i answered: NEVER! He gave me the suggestion to get it inspected, cleaned up and see if the problem persists.

I convinced my father to take it to the SVC and then get the throttlebody opened up and cleaned. At first when the suggestion was made to the SVC guys, they gave us a puzzled look and told us that this is not required and they have not been told to do this by Ford. We persisted and they finally agreed. The throttle body was opened up and inspected: it was found to be compltely covered in dark sooty layer of gooey deposition on both sides.



Pic 5: A reference image of a dirty throttlebody Vs the clean one. Mind you this is not from my Ford Ikon

They then used cleaning spray and removed all the carbon and gooey deposition from it. The throttlebody was put back into the designated area, bills were paid and then i asked my father to drive back home and give me a feedback if the whole process made any difference at all! So here comes the kicker: The ignition was turned on and the vehicle started immediately. The engine idling was normal, the tachometer stopped dancing. We then took it on the highway and suddenly the old love for the car re-emerged in my dad's eyes. The vehicle became super responsive and even a light dab on the throttle, the vehicle would want to lunge forward in a hurry just like it was when new. The "Josh machine" was back. We then tested it on speed breakers with the AC turned on at full blast. Even then the vehicle would now happily pull from 3rd gear without breaking any sweat. So it was pretty evident that @psr sir's advice made a hell lot of difference to the performance of the car and saved my family quite a lot of money in the due process.

It also opened up my eyes that throttlebody cleaning is a must on motorcycles as well. So armed with this new knowledge gained from the experience above, i had already made up my mind that the throttlebody cleaning on my future bike will be carried out @every 20-30,000 kms. The CBR 250R has now clocked about 21,000 kms on the ODO. I have also witnessed a bit of tacho dance during cold starts on this bike and engine stall when decelerating during one or two odd times. So as a precautionary measure, the throttlebody will be whipped out and cleaned up properly and then the observations will be shared on this thread. However let us keep this for a dedicated post at a later date. In the mean time, for those who want to learn more about throttlebody cleaning you may refer to this simple reference video which should give you an idea about the same.

Reference video for throttlebody cleaning:



One must bear in mind that the throttlebody in Honda CBR 250R is of electronic nature where the butterfly valve is opened and closed by a motorised unit, reduction gears and there are a multitude of sensors monitoring it. So one has to be extra careful not to touch the butterfly valve or else the settings will go haywire and the butterfly valve may not work properly.



Pic 6: Throttlebody instructions as mentioned in the workshop manual of Honda CBR 250R

I hope this post was of some use to the readers here..

Cheers,