Author Topic: 09 450 valves???  (Read 4445 times)

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Offline chipped tooth

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09 450 valves???
« on: August 03, 2016, 11:39:25 AM »
I've had myself an 09 450 for a bit now and decided I wanted more power.

So I've upgraded the crank with a coated Carillo rod and a 13.5:1 piston witch once I'm done it should be around 14.5:1

It already has stage 2 cams

I'm going to port the head and upon removal of the valves they are stainless instead of Titanium

Should I just stick with the stainless or go back to Titanium?
Either way the valves and springs will be replaced.

Does anyone know if cracking into the computer is the same as the crf?

Offline LukeG

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Re: 09 450 valves???
« Reply #1 on: August 03, 2016, 08:37:56 PM »
For longevity I would stick with stainless valves but that also depends on what you are using your bike for.
1990 KX250 - Wanna be road racer!
2007 DRZ 462 Motard

Offline KXDINO

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Re: 09 450 valves???
« Reply #2 on: August 04, 2016, 08:23:25 AM »
if you are chasing power go with 1 piece titanium valves , there is a aftermarket company that does them , most oem ti valves are 2 piece that are welded together and they can break as i recall , yamaha yz250f 06 model had a recall on these and replaced them as they were breaking near the weld , the 1 piece valves solves that problem , another thing is to get is some decent valve guides fitted as the oem guides are average , this will make the head last longer and the head is very important on these 4 bangers especially if you are chasing power.

Offline chipped tooth

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Re: 09 450 valves???
« Reply #3 on: August 04, 2016, 04:53:49 PM »
I'll look into the 1 piece titanium valves, I thought the oem 09 450 were 1 piece?

I planned on installing bronze guides with the new valves

My biggest concern is the added spring pressure associated with stainless valves...

I sure know there is a big price difference! But anything associated with power usually is lol

Offline KXDINO

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Re: 09 450 valves???
« Reply #4 on: August 04, 2016, 05:46:20 PM »
i know the 250f are 2 piece as i seen them break there and i would say the 450 as well as it cheaper to manufacture , go 1 piece for peace of mine. I put stainless valves on the inlet on my 09 250f and they have lasted well they come with stiffer springs and never had a drama , left the exhaust std titanium , you dont want to run these engines lean , if you put pipes and cams etc etc with out a retune and they run lean expect the exhaust valves to break and punch a couple of holes in the piston ,

Offline chipped tooth

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Re: 09 450 valves???
« Reply #5 on: August 05, 2016, 05:34:50 PM »
I have Xceldyne Titanium valves on the way!

I know with a laptop and obd cable you can get in the crf bikes tune.....
I'm hopping this will work on the kx too!