[Keith T]

Hello all,

This is my first post. I recently purchased a new 2020 250 CRFL, which just turned 500 miles. This engine is pinging or detonating under normal acceleration, especially around 6-7,000 rpm. The rattle is concerning; I let my brother take it for a ride and he agrees, detonation. (we are both retired auto techs). Is anyone else experiencing this with their 250L? Thanks in advance!

[JimDirt]

Welcome to the site !!

Are you running Ethanol Regular ?? , try upping the octane and/or staying away from the Ethanol based gas , see if that quiets it up ...

Usually pinging is from either the engine running hot or not burning the mixture efficiently , you can help fix it by upping the octane , as mentioned , or lowering the heat range of the spark plug to get a cooler burn , or if you are doing a lot of in town slower traffic riding , then maybe a radiator fan to cool the engine temps down a bit ... any and all of those would stop the pinging , is it common with that bike ?? ... I can't say , as I have no first hand experience with it , but I do know the other Hondas benefit from everything I mentioned ... , the issue is , airflow thru the radiator is what keeps the temps down , if your putting around in traffic , it is going to get hot , so without changing the riding , the only option is to try to cool everything down

Most of the time these bikes come a bit lean from the factory to pass emissions , so richening , never hurts the situation and usually improves it .. , but with EFI , unless you have the ability to change the mapping , your options are , spark plug heat range , and engine cooling , or higher octane gas .... hope that answers or attempts to answer your questions ...

[Keith T]

Thanks Jim! Yes, I am running 91 octane ethanol-free fuel.(even in my lawn equipment) This occurs at regular cruising speed on the road. I will call Honda today, as the bike is under warranty.

[JimDirt]

Yea , something is up then ... it should not ping at all with 91 ... and especially at cruising speeds

[Aussiecrf230]

Yes it's new so Honda should be looking after it.

[Duck851]

Cam chain rattle?