High comp or no

My 2006 yz450f has a high comp piston in it ever since I bought it and it feels like there's no rev limiter and I can't be in a tall gear going slow or the chain will slap everywhere do you guys think that it's the high comp piston doing this or something else?

Chain needs to be tightened.. As far as the limiter question I have no idea. My 08 also slaps if it is too loose in the slightest

The chain slap is normal, DO NOT tighten the chain beyond the minimum limit in the manual, or you will risk breaking the chain and/or the rear hub, which you will not enjoy.

 

High compression tends to bring about the greatest power increases at low engine speeds, rather than high, and can even restrict the engine's ability to run to the top of its rev range.  The '06 is not particularly fond of running much past 10,500 because the power falls off pretty sharply after that.  With the rev limit set at 11,500, you'll rarely run into it except in low gear. 

The chain slap is normal, DO NOT tighten the chain beyond the minimum limit in the manual, or you will risk breaking the chain and/or the rear hub, which you will not enjoy.

High compression tends to bring about the greatest power increases at low engine speeds, rather than high, and can even restrict the engine's ability to run to the top of its rev range. The '06 is not particularly fond of running much past 10,500 because the power falls off pretty sharply after that. With the rev limit set at 11,500, you'll rarely run into it except in low gear.

Do you think I should swap it out since I rarely ride trail and I mostly ride track

It doesnt make that much difference. If your bike is exhibiting bad behavior at low speeds such as chain slap etc I would look at gearing before I worried about the small difference a hc piston makes.

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