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FriscoKLR

'06 450 high compression piston recs?

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Gonna do a top end rebuild on the bike this winter and starting the research early. Looking at trying a high compression piston to make up for the high elevations where I ride.

Any recommendations?

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the 06 already has almost a 13 to 1 comp ratio stock. how much do you really need. gas is gonna be an issue.

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the 06 already has almost a 13 to 1 comp ratio stock. how much do you really need. gas is gonna be an issue.

Key words here are "high elevations"....13.5 will suit you well.

Must be from "lower" Colorado lOL

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i live and ride in colorado and my 06 seems to run and have plenty of power with the factory compression. i don't ride in the mountains or above 7000 ft but i would think that proper jetting for altitude would make a much bigger difference than compression. since if you are riding in the mountains, the altitude and air density are gonna change a bunch. will compression make up for that?? i guess give it a shot and see if she holds.

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the 06 already has almost a 13 to 1 comp ratio stock. how much do you really need. gas is gonna be an issue.

I dont know where you get those specs, but stock compression ratio is 12.3:1

http://www.yamaha-motor.com/sport/products/modelspeccompare/209/1353/0/compare.aspx

Really on the 450 you probably dont need more power. But up in colorado, I can see the need. Wisecos are easily obtained.

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I like JE and CP pistons. They are both really good products. The Wisecos used to have issues with being cut a little small but from what I hear, that has been resolved. If you do get a Wiseco , check the clearances. You should do this with any piston, but I would double check the Wiseco just for peace of mind.

At altitude you need all the help you can get, so I would definitely go with the 13.5:1 with good fuel.

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I dont know where you get those specs, but stock compression ratio is 12.3:1
A lot of reasonable people would say that 12.3 was "nearly 13:1", wouldn't they?

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A lot of reasonable people would say that 12.3 was "nearly 13:1", wouldn't they?

With that mentality 50hp is "nearly" 55hp, right? :thumbsup:

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Depends on one's perspective. In our reality of 450cc four strokes, it ain't even close, is it?. But in a realm of 1 liter road bikes (not sport bikes), or say, outboard motors, there's very little difference.

Someone familiar with street cars would think that 11.5:1 was serious compression, and 12:1 was only for race cars. Beyond that, to a lot of people, is "nearly 13:1".

People carry their own realities into every "world" they enter. It's somewhat like the fact that for most people, "modern history" began on their birthday. :thumbsup:

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Depends on one's perspective. In our reality of 450cc four strokes, it ain't even close, is it?. But in a realm of 1 liter road bikes (not sport bikes), or say, outboard motors, there's very little difference.

Someone familiar with street cars would think that 11.5:1 was serious compression, and 12:1 was only for race cars. Beyond that, to a lot of people, is "nearly 13:1".

People carry their own realities into every "world" they enter. It's somewhat like the fact that for most people, "modern history" began on their birthday. :ride:

I love getting this stuff out of you! I sit and slowly read your posts and am dumfounded by how your mind works, in a good way. :thumbsup: Whereas most read my posts and are dumfounded by the nonsensical crap that comprises them, myself included.

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I live at 9200 ft. and during the summer, albeit a shorter season than most, I ride at 8000-12000ft.

Based on 51hp at sea level, Im losing 13 hp (25%) at 9000 ft., 16 hp (31%) at 10500 ft., and 18 hp (35%) at 12,000 ft.

12.3 to 13.5 will get me a fair chunk of that hp back.

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