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Old 09-11-2016
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Oldfatbeerman Oldfatbeerman is offline
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WR 450 Auto Decomp not working .

Brains trust ..... 2009 WR 450 , auto decomp is not working with kick start or elec start , what is the most likely reason for this component to stop working . I have had a look at the workshop manual and it only says to check the operation of the auto device , leaves me a bit short on knowledge . Also , I check a couple of online parts fishes and neither of them show separate parts available for the auto decomp on the exhaust cam , just the complete cam shaft for a tad over $300 dollars , I am hoping this issue is not going to be any where near that expensive to fix , any ideas or cheap fixes known ?
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Old 09-11-2016
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Quote:
Originally Posted by Oldfatbeerman View Post
, any ideas or cheap fixes known ?
Hotcams stage one exhaust cam, much betterer thing

just get one, bolt it in, thank me later

ya welcome

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Old 09-11-2016
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Originally Posted by Blulu View Post
Hotcams stage one exhaust cam, much betterer thing

just get one, bolt it in, thank me later

ya welcome

What Lu says. ^^^^

The design of the system never worked properly from day dot.
You can run the YZ-F cam timing which helps, also check the valve clearance on the decomp valve is within spec.

The hotcams cam fixes the intermittent start issue for good at the same time.
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Old 09-11-2016
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Cheap fix!

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Old 10-11-2016
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Cheap fix!

Nope, sorry SS.

There's so much drag in a WR450s drive train that pulling in the clutch does SFA. The bloody things struggle to: a) Find neutral and b) Start in neutral.

Bite the bullet OFBM, the Hotcams stage 1 exhaust cam transforms the bike, in smoothness, low-end pull and most importantly, starting.

That cam, a jetted carb and a Li battery is all they need to be a 100% reliable starter.

p.s. If the float height isn't spot-on they won't start on weird angles either.
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Old 10-11-2016
ricknaz ricknaz is online now
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Is it worth putting hotcams in a bike that doesn't have any starting problems just for the power increase? Can the power tuner cope with the cam change in the 12-15 models?
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Old 10-11-2016
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I have never had any issues starting this bike until this decomp issue , I am also happy with the power and how it is delivered , the Hot Cams cam ...... it increases bottom end torque and mid range and top end ?

Kind of hard to believe that seeing as most top end gains are usually at the expense of bottom end torque ..... and for single track the bottom end is where it spends plenty of time .

I Still would prefer to just replace the worn components and keep it a stocker even with the power gains , I don't use all it has now , so more will be just a waste !
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Old 10-11-2016
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I still would prefer to just replace the worn components and keep it a stocker
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The design of the system never worked properly from day dot.
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Old 10-11-2016
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That's actually a decompression lever...... but I take it back anyway.
It's seems that years head doesn't have the hole to put the manual decompression thingamigig.
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Old 10-11-2016
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Quote:
Originally Posted by ricknaz View Post
Is it worth putting hotcams in a bike that doesn't have any starting problems just for the power increase?
Not IMO. The stock FI bikes ride great with a tune.


Quote:
Originally Posted by ricknaz View Post
Can the power tuner cope with the cam change in the 12-15 models?
Easily
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