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


The beauty of this mod job is even if your vehicle is currently not having any earthing problems, making the line direct from the -Ve terminal to the earth wire/to the chassis will have a profound effect on your bike. The intensity of the spark from the spark plug also increases according to my observations which along with proper fuelling will result in better ignition = better response at low end and mid range and thus, quicker acceleration and slightly improved FE. This has happened on my bike so i am pretty confident that any DC circuit based motorcycle owner will notice something positive on his bike with carrying out this mere mod job.

Cheers,

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

some epic stuff you have discovered . will be doing it today. was anyways visiting SVC for service.
i sent you a pm probably 15 days back. guess you missed it.

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

The Earthing problem is a known issue with ZMA and CBR 250 R...but the problem does not come out so blatantly as in @ Shv18's case. There will be intermittent drop in performance, stalling when throttle is closed and clutch pulled in to shift gears, and sudden reluctance of the bike to start both in Cold and Hot conditions.

The improvement in better Low to Mid RPM ,and also at higher RPM can be felt, EVEN in bikes Running without a hitch...
This happens because the Earth Routing in ZMA /ZMR and in CBR250 is through the Engine Casing.>to Engine Mounting Bolts > to Chassis ...any Oxidation of Aluminum alloy(the Crank Case) will make it a non conductor since aluminum oxide is poor conductor...The bolts which are again coated against corrosion either cadmium or zinc coating also becomes resistive when oxide forms...and of course the chassis itself is made of Iron and Iron rust is a poor conductor.
If we have to diagrammatically represent the CBR 250R Electronics circuit here is how it will be.....
Sorry for the Crude representation....



One can see how the Entire Negative return to battery , and hence proper completion of circuitry , is dependent on the Engine Mounting Bolts, to chassis connection, as well as the Loom earth return depends on the RR being properly tightened and a hope and Prayer that no loose contact develops.
Even if we have just an Ohm of resistance in any one of these bolts, Casing or Chassis connection , it will make the operating parameters of the ECM go bananas..
The ECM' s values are sane and operational only if the ECM return path to Battery negative has NO RESISTANCE. We all have seen how the light in our home flickers when the switch for the lights develop loose contact...it is the same happening in the bike.

One of the most important sensor ie., the O2 sensor has a critical operating point 0.45 ~ 0.5 Volts. Any voltage output LESS than this voltage is Lean AFR and more indicates Rich AFR. The earthing for the O2 sensor is the engine itself , while the ECM which senses this voltage has the CHASSIS as Earth Reference .
Now imagine what will happen when the Chassis is no longer properly referenced to battery negative due to loose contact. The ECM can no longer be able to work properly and deliver correct AFR.
The Ignition coil is also referenced to the Chassis and a loose contact to battery negative will Decrease the Spark Voltage and Current .
So in many ways even a small Loose contact robs the Engines performance in many ways , in a Fuel Injected engine...
Providing a Separate Earth Wire from Battery Negative to the Wiring Loom Earth with a Separate 10mm insulated wire will stop all the guessing out of Loose contact problem and provide better repeatable performance from the engine.
Hope this is useful...

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


i will try it out asap. and if this really works. it will be a breakthrough in terms of "finding" some serious design flaw.

why ? coz i am regular on CBR international forums as well. though the problems reported there is not as serious as [MENTION=29396]shiv[/MENTION] however almost everyone has one/multiple times faced engine cutting off. also the machine sputtering at lower rpm's and similar issues. i would suggest mods to make this sticky.

great find shiv and thanks a ton to [MENTION=32286]psr[/MENTION] sir and other folks who helped out in isolating this issue and helping us out with some kickass info.

thanks again.

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

Credit to @shiv18 for the patient way he followed the trouble shooting with me....this is also presented in a different form in the CBR250.com also ( you are a member) but was shot down my Mod as the presentation was not done properly..... Pulsar Battery clips made by SWISS were used for making the cable later on....use a 10.sq.mm insulated wire for this...length will be 60cm..
Please revert back once you have done this mod..it will be useful for everyone..
The battery clips...and the cable....






Here is the Link...

UPDATED: Solution to RARE & Bizarre CBR250R problem - Honda CBR250R Forum : Honda CBR 250 Forums...

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


by the time you posted this comment. with all credits to the FM's i re posted this on CBR250 forum again.. lol.
i will pick up wire on the way and some clips and will do it today itself.

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

There are some more Findings and Experiments which [MENTION=32641]shv18[/MENTION] will share once he has time and also confirmation on results....

Guess we will be seeing more members successfully ,trying out this Earthing wire Modification ,and share their experience here for all to benefit.

If any glitches are found , please do post the same ,since it will let us all learn..esp me..since I am Keen to learn , and ever thankful for the opportunity.

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


with every new mod found for "free" which also can boost performance makes us go mad like kids wait out for sweets. no more interested to sit in office.
killing time. cpl of hours and i will be on the way to SVC. and will be eargarly waiting for the rest of mods.

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

Sir, his issue is one of a kind; haven't even heard about this issue till date & certainly not on mine; I guess this should occur only if the bike is left unused for few days. But even then, there're some folks (I know Sheel parked his for over a month) who've taken the bike after long parking & still haven't seen this issue.

I guess its like CBR's engine seizure. Except mine, none other have experienced at that stage.

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

though its not related but the similar instance might relate to random engine shutdowns which a few members did. also sometimes Fi light coming up when starting.
The validity can only be tested over a period of time. but involves no to minimal costs hence giving a try wont harm

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

Thanks for the post...it lets me share what other riders are going through internationally...

Not Just CBR 250R but Owners of Fireblade, Cb/CX 500 , VTX 1800 ,are also plagued by Earth Loose contact problem. Not guessing but here are some links ...

The Fireblade Thread on Earthing complaint ,and the VTX 1800 "Ground Fix"...Common ground earthing problems... Just some samples to make an interesting read .






Why does my ground have 12 volts on it...? - Honda Motorcycles - FireBlades.org





Battery Charging Problems .....



The VTX1800 "Ground Fix Problem is very detailed, and explains how and why the Common earth corrotion/Loose contact takes place. The corrective steps are also note worthy

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

A big thanks to PSR sir and [MENTION=32641]shv18[/MENTION] for sharing such a valuable information regarding the earth wire modification,in fact i tried it on my bike just as a precautionary measure but i was in for a big surprise .....drastic improvement in low and and mid range....couldn't check the top end though, throttle response is much more sharper.

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

Thank you for the extremely knowledgeable inputs on this thread.

Through the latest discovery of the earthing wire 'mod', what I don't understand is, how can something as small as this 'boost' performance as significantly as 15% over stock. Does this mean all the bikes coming out of the factory have faulty earthing and the manufacturer isn't aware of it?

To be more precise, I'm not quite sure if this is being categorised as an issue with the OP's bike or as a manufacturing defect that hinders the engine from delivering its maximum performance?

Is this perceived improvement in performance subjective or is it quantified?

I don't mean to sound demeaning to the efforts being put in and the knowledge shared here, so please don't take this negatively. I'm only trying to put a constructive argument on the table for the benefit of everybody.

EDIT: Also, my CBR is running perfectly with no issues. What's the best way to find out if there is an issue at all? Apart from the trial of doing this mod.

Regards
Suhas

Sent from my MI 3W using xBhp Connect mobile app

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

Mr.Suhas, thank you for the post seeking clarification...
The whole exercise of the add on Earth wire was a result of the thread starter's CBR250R failing totally due to Electrical fault.ie., bad Negative return or bad earth fault.. If you read the thread fully, you will notice that the bike was running perfectly before running into problem progressively....and you would also have noticed how only through systematic trouble shooting the actual problem was found.
When the problem was solved through a Secondary Earthing by a direct wire from battery negative to the Earth wire cluster on the RR unit, there seems to be a betterment in the bike's engine behavior. ie., better low to mid performance.
If you had gone through my reply to this, it will be clear that better earthing has been the reason....
As to the claim of "Increased" performance, my feel is that the thread starter felt so since he had been facing bad Earth(-ve) problem causing lack of acceleration, including Misfires , and after a ride with problem sorted out felt , better acceleration due to better Negative return.So Definitely it is subjective.

The amount of loose contact Before Wire connection will determine how much more the engine becomes responsive, post the wire connection.

Another member had also tried and had better acceleration and is reported just a post before yours. His bike had no problems at all and he was also able to feel better acceleration.

For any member to know if the CBR250 he owns has this problem or not, Simply start the engine and measure the Voltage between Battery Negative and the Green wire cluster on the RR unit.. any voltage read on the Digital Multimeter is an indication of Negative Return Fault. Depending on the Severity of Loose Contact the voltage will vary...ie., more loose contact= more voltage.( read the Fireblade owner wondering why there is 12V on his earth connection...a case of extreme loose contact.)

This add on wire is not expensive, and prevents bad earth fault .

The problem seems to involve other Honda bikes also, and I had given a link to some of them in my reply.

The write up on the VTX 1800 is very well written with the cause ,and cure for the problem...

The post and clarifications are to ensure that members facing bad Earthing(negative return) problems have a possible solution and are not stranded...

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

adding to that a few more points or issues that can crop up due to same earthing issue.

1> engine sputter , low pickup
2> random shutdowns, everything going blank ( can be one reason)
3> electrical malfunction ( less/more voltage, loose contact)
4> blown fuses.

a small loose contact can literally end up being PITA and we have seen it.