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Discussion Starter #1
Hi all
Wondered if any one can help
Recently my 2012 abs model has started having trouble starting
First thing in the morning I try and start the bike and it will just crank and not start, try again and it may start then cut out, third time it will usually start then run fine no apparent issue, after this rides fine all the way to work
But once I finish work the bike will have the same issues starting again
If I turn it of and re start once it鈥檚 running it鈥檚 fine
Seems to struggle starting up once left a while
Wondered if anyone had experience this or had any possible solutions
Thanks all
Sorry for the long post 馃檪
 

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Is the gas fresh?

I'd start by checking the battery voltage. Should be 12.7V or more before starting. Then check as you are cranking. It should stay above 10V.

If that's OK, I'd confirm your air filter is in good condition.

If so, I'd add 1oz per gal of Techron Concentrate fuel system cleaner to a fresh tank and run it through. Just a bit of deposits on the injector may be enough to give you starting problems. I use it once a year in all my vehicles.

Also try opening the throttle slightly as it's cranking. Sometimes that helps.
 

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Discussion Starter #3
hi jkv,
Thank you very much for all the advice there,
The fuel is fresh,
So tomorrow I will start from your first step and start working my way down your list of things to try
Really appreciate that bud
 

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Is this difficulty-starting condition worse in cold weather?

Test and measure resistance your IAT and ECT at room-temperature and boiling. These tell ECU you have cold-start condition and it enriches mixture by +20% or more. This is similar to choke on carburetors and adds extra fuel needed for cold-starts.
 

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Discussion Starter #5
hi Danno
Thank you for the reply, it has been worse in the cold weather and when the bike is cold I guess or left when I park it at work in the morning then go ride home , how would I go about checking the resistance at the two sensors and we鈥檙e abouts are they? Thank you
 

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Let us know what works for you.

Hopefully something simple.

I may have heard something about a stalling issue with the CBR, and that Honda may have released a service doc on it.

May not be the issue for you, but you could see if you can find it. Might be related or point you in the right direction.

What is your hot idle set at (not sure if it's adjustable or not though)?

Does it high-idle when it starts when cold?
 

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Good point, high-idle on cold-start points to IACV which is located on right side near throttle-body.

IAT is part of throttle-body and wiring comes out on 5-pin connector along with MAP and TPS signals. Which brings up another point, which is TPS must be adjusted properly with idle-switch making proper contact when throttle is released. Otherwise, ECU will never know throttle is closed. Without that closed idle-switch, ECU won't use IACV to control idle-speed.

ECT is triangular connector underneath throttle-body and has 3 terminals. Two provides data for ECU and 3rd pin runs dash-gauge.

There's 6-pages of tests for ECT in addition to resistance-test I mentioned. You'll also need to test reference-voltage, output-voltage and test for shorts to sensor-body. Along with some key ON/key OFF voltage-tests for wiring shorts. Apparently ECU can sense ECT state even without key inserted or turned ON. ;)

I recommend getting manual and going through these tests 1-by-1 and measuring voltages and resistances to verify proper operation. At sensor itself and at ECU-connector to test wiring in between. Luckily you're outside of U.S. where a lot of testing tools are available. Not sure why they're not provided for U.S.
 

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Good point, high-idle on cold-start points to IACV which is located on right side near throttle-body.

IAT is part of throttle-body and wiring comes out on 5-pin connector along with MAP and TPS signals. Which brings up another point, which is TPS must be adjusted properly with idle-switch making proper contact when throttle is released. Otherwise, ECU will never know throttle is closed. Without that closed idle-switch, ECU won't use IACV to control idle-speed.

ECT is triangular connector underneath throttle-body and has 3 terminals. Two provides data for ECU and 3rd pin runs dash-gauge.

There's 6-pages of tests for ECT in addition to resistance-test I mentioned. You'll also need to test reference-voltage, output-voltage and test for shorts to sensor-body. Along with some key ON/key OFF voltage-tests for wiring shorts. Apparently ECU can sense ECT state even without key inserted or turned ON. ;)

I recommend getting manual and going through these tests 1-by-1 and measuring voltages and resistances to verify proper operation. At sensor itself and at ECU-connector to test wiring in between. Luckily you're outside of U.S. where a lot of testing tools are available. Not sure why they're not provided for U.S.
Ya...I knew that...

Not really.

That's why we keep Danno around. I can spit-ball - and he fills-in the details!
 
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