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Modified 450 dynoing 45 hp?

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Hello guy's i need a bit of help here as i was at the dyno today dynoing my rmz to get a custom tune for my power commander and the bike just didn't want to give more than 45 hp graph showed she fall's flat by 8 to 10,200 rpm theres just absolutely no top end. I got 13:8:1 piston with carillo rod ported head with 1049/516 web cams stock valve springs tuner told me she was floating at those rpms because of my cams being to aggressive for my valve springs what do you guys think?

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Get ready because this will be long winded as I have been through this with my 2012.

Your tuner is correct, mostly. You are at the very limit of your stock valve springs (which is why WebCam lists upgrading your springs as a necessary mod). They will not hold up for long with your mods. However, the end game is that the bike is running out of fuel up top. Upgrading your valves may show you a slight improvement by stopping the floating, but will still not let the bike rev much past 10-10.5k RPMS considering the bike reaches peak at about 7.5-8k.

They run rich until you get to about 10k and then the bike just falls on its face (the 08-09 are considerably worse than other years, we will call it growing pains). You should be over 45rwhp in 100% stock trim, and should be sitting at about 48-50hp with a "decentmap alone. Leaning the bike out across the board will give you noticeable boosts off bottom all the way through the RPM range, but the bike really benefits from adding fuel up top so that it can rev a little further. The other negative from the grind you chose is that you will never gain a SUPER strong top end from your bike. You can't gain a bunch off the bottom and expect not to lose up top. 

I am running a similar set up CP 13.5:1 piston, Carillo rod, porting, 208/540 grind webcams, injectioneering throttle body mod, and valve work, but on a 2012 RMZ. I had my bike on the dyno and saw 62rwhp peak out of my RMZ with a 100% fresh motor and custom remap on stock ECU on MR Pro 6, but I wanted to keep the power smooth and rideable. I bet it would be even better with the Vortex if I had a custom tune written. 

I would expect you should see low-mid 50's with a good tune and your mods. Keeping in mind that the 08-09 were down considerably on power.

I caution you to be careful though. This bike is easy to mod past the point of remaining enjoyable and rideable for the vast majority of us. 

Hopefully this helps and is not overly confusing. 

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Well the fuel she needs on top i can control it with the pcv at the dyno but i really need to change those springs. I was thinking in installing OEM camshafts till i get my money up and send my exhaust cam for a regrind for extra top end. But do you think that springs are the big problem?

Btw wich springs do hold up high lift cams? I know webcams makes them but any other?

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Yes, the springs are going to help. I am running Kibblewhite valves and spring kit since WebCam recommends them and sells them.

PC, Kibblewhite, Del West, RD valve springs, faction etc. They will all hold up for your use. You can contact any of them and they will set you up with what you need. Your valves don't really need to be replaced but I would recommend replacing the guides, retainers, and seals while you have it apart so you would probably be better off just buying an entire kit. 

 

Edited by BDubb106
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Another option is shimming your valves to eliminate float. That is what Yosh did when I had them build my first motor. However I still used Ti springs. 

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