pinging and jetting

I'm having some issues trying to jet my bikes and I'm wondering if this is normal or not...when i have the proper jet sizes installed the bikes sound weird and all i can think of is that it is pinging/detonation like crazy! I guess the next step will be finding some race fuel?.

At sea level and 70 degrees I had the bikes jetted perfectly and they run on 91 pump gas no problem. But now i am at 2500' and it is mid 80's and the bikes are rich and unresponsive. I found that if i run the bikes one jet size too rich the bikes do not ping. But when i try to lean them out they start to sound like nitro engines. At this lean state they preform fine but sound like they are running super ragged.

I'm using 91 octane ethanol free fuel with 32:1. The bikes I'm working on are a 2000 yz125 that has a stock motor and PC pipe and a bone stock 2007 rm250.

If the bike have a bouncy idle ill check for air leak. Have you tried to retarded the timing 1 or 2 degrees ? It can help with pinging.

If the bike have a bouncy idle ill check for air leak. Have you tried to retarded the timing 1 or 2 degrees ? It can help with pinging.

the 125 idles normally, but the 250 has a strange low idle issue that i haven't figured out

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