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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!

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 ...

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.

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

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

Cam chain rattle?