Thanks in advance for any help.

I have a 94 Trx300FW. It is a fresh rebuild from the ground up.

Here’s the list on the engine:

Bored .040 over with Wiseco piston/rings
88 cam and mild P&P
Twin Air filter
Super trap full exhaust

Carb is fully rebuilt and I had some exhaust pop on decel so I bumped up the jets to 128/42. I also had some spark knock before, or at least what sounded like it when I had been riding for a while.

Now, exhaust pop is gone but I’m still having some spark knock after it heats up, about 30 minutes of riding. No problem if I’m easy on the gas, but if I gun it, it’s definitely there. I’m running 87 standard pump gas. I feel like higher octane gas may help, but I also feel like if the pump gas was the issue I’d notice throughout my riding time.

The other slight issue is after it warms up at idle after a few minutes, it idles fine but bogs if I give it a lot of gas. Once it’s in gear and going it’s fine. Accelerates smooth and plenty of power. But in neutral it just sounds like it’s bogging. I feel like that more of a fuel/air mixture issue and unrelated to the other.

Again, thanks for any help.

Thanks in advance for any help.

I have a 94 Trx300FW. It is a fresh rebuild from the ground up.

Here’s the list on the engine:

Bored .040 over with Wiseco piston/rings
88 cam and mild P&P
Twin Air filter
Super trap full exhaust

Carb is fully rebuilt and I had some exhaust pop on decel so I bumped up the jets to 128/42. I also had some spark knock before, or at least what sounded like it when I had been riding for a while.

Now, exhaust pop is gone but I’m still having some spark knock after it heats up, about 30 minutes of riding. No problem if I’m easy on the gas, but if I gun it, it’s definitely there. I’m running 87 standard pump gas. I feel like higher octane gas may help, but I also feel like if the pump gas was the issue I’d notice throughout my riding time.

The other slight issue is after it warms up at idle after a few minutes, it idles fine but bogs if I give it a lot of gas. Once it’s in gear and going it’s fine. Accelerates smooth and plenty of power. But in neutral it just sounds like it’s bogging. I feel like that more of a fuel/air mixture issue and unrelated to the other.

Again, thanks for any help.