HONDA CRF 250RN stalling

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Joined: Fri May 01, 2020 3:04 pm

HONDA CRF 250RN stalling

Post by bma »

I explain my problem: this is a completely new cross motorcycle. The engine is stalling when rapidly opening the throttle. As if it was too poor

Everything seems normal:
TPS: voltage curve OK at slow or rapid opening (or closing) .

MAP sensor: idem, value within theorical values

CKP, alternator seem OK (apart from the fact that the voltage when engine running is maximum 0.2 volts above the battery voltage). The two parts have been replaced (only available as a unique part) without any change.

Injector seem OK, the only doubt is the curve of the injector Voltage which seems strange (either the injection is cut a very short time or the ECM switches it in 2 phases) the pulverisation is OK and the fuel pressure is constant.

ECM: the customer has had the chance to have another reliable one for testing without any amelioration.

ECT: Water T° has been change by a precedent mechanic

IAT: Air T° no value available.

Curves ARE available but probably too heavy

Does someone could help me: what else should I check


Posts: 8
Joined: Fri Oct 07, 2016 12:11 am

Re: HONDA CRF 250RN stalling

Post by CycleImp »

If you are snapping the throttle right from idle then it is not uncommon for this to happen. If you hold it slightly above idle than snap it does it do it than? What is your idle speed at? Is the bike all stock? What year? What is the TPS voltage at closed throttle?

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