The quest for more power begins.....

Well, Just ordered a nice set of hotcams, a hotcams shim kit and a JE 12.8:1 piston kit.

I got the JE 12.8:1 piston kit rather than the JE (or Wiseco) 13.5:1 kit because of fuel quality concerns where I live. The 12.8:1 piston should provide a nice little boost to power over the stock 12.3:1 in my '05 WR450F.

As for the Hotcams, I have decided to get them over a YZ cam because for the price I have to pay, both the YZ and hotcams exhaust cams cost the same. May as well go for the set while it's all apart, hey?

Here are the gains of a set of hotcams over the YZ cams:

Should be a very nice boost over my stock WR cams!

They should be here in Australia early next week from atvunlimited on ebay, I will have to post some pics and maybe a guide or two on how to change a piston and how to re-shim seeing as no one with a Yamaha usually does these things. :mad:

I have my engine all torn down at the moment, I must say that I was taking it real easy and it only took me 1/2 an hour. For any of you out there thinking of doing the same, don't be worried. It is a very easy job to do.

I will let you guy's know how it all goes.....

yes, keep posting the updates as you go .. for some of us that are not so technically minded it will be an eye opener and a good reference point.

did your '05 really need to be torn down and rebuilt so soon ?

No, it didn't really need to be torn down, but.........

I have about 5,000kms (~3100 mile) on the clock now and I started hearing a noise that was not normal. I checked the valve lash and the right inlet was opened .15mm out of spec. That is not normal, so I tore the inlet cam out to check the valve cap out. They seem OK, but the top of the right valve stem looks a bit shiny compared to the other inlets. I thought I may as well check the other side now. I took of the head, there was a fair bit of carbon build up on the top of the piston and the head. I cleaned up the head, all the valves still look like new, not cupped or anything. I should have taken pics of the carbon build up, but I will of everything else.

Anyway, pulled the barrel off (one more nut) and took the piston off to give it a clean and check. I must say that I am impressed with it all, there is no signs of detonation, just carbon build up. I haven't bothered to check the piston ring gap, I thought may as well throw a new piston kit in anyway.

So now I sit and wait for my goodies to come from the states! I have always wanted to throw in a cam weather it be a YZ exhaust or the set of hotcams. My procircuit exhaust adds a ton of punch to the bottom and mid, but I feel it goes flat on top. To be honest, I wasn't going to get hotcams untill I saw them for $US300 a pair! As you know, they are like $300 each here! I also thought if I throw in a piston now, it should be good for another 5,000kms.

ok, glad to hear it - my '05 has 4,312 k's on her already (and has certainly earned quite a few of them). Apart from the usual oil/filter/air filter and valve checks she still runs like (almost) new !!

my GYT-R pipe gives me a similar result that you get from the PC and at the moment i'm happy with that - just glad to enjoy the ride ...

... still gonna keep watching these updates though !

Hey Alley Cat.......

What's the latest update? How long before you get your new piston and cams??:cheers:

You must be going nuts having to wait:banghead:

How much power gain (HP and Torque) does the Hotcams give you over stock and over YZ cams?? I wondered if it's worth it for me to upgrade my yz exhaust cammed Wr to hotcams??

hey alley cat, any updates on how everything went?

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