Big Bore WR450

Can anyone help me in finding a big bore kit for my 03 WR450? Thanks, Dirtmizer.

Why would you want to go bigger on that thing? :thumbsup:

Wiesco 490 cc kit in 13.5 compression. If you can handle all that torque and power. :thumbsup:

What a crock, even the top dogs(Reed, Ferry, and the FROG) detune these bikes to make the max power more usable and now you want more??. Get real. Jet it correctly and it is quite the weapon!

Are you taking it to the drag strip? Super motard? :thumbsup:

As long as people are still putting turbos on Hayabusa's and ZX12R's I find nothing strange or wrong with wanting more power for whatever reason.

Maybe his driving style warrants it...

Maybe he wants to run a taller gear ratio without giving up any of his low end...

Who knows?

I don't think any of you should be judging this guy. I don't find it all that unreasonable. If you can't help him with his question, why comment at all?

Nomadak I see your bikes and car are all stock too !!

yeah really! I have yet to open my WR450F full throttle since I bought it. Already has tons of power!

Why would you want to go bigger on that thing? :thumbsup:

Personally my 04 scares the living crap out of me!! Bigger front sprocket going on to soften it a bit!!! :thumbsup:

Wiesco 490 cc kit in 13.5 compression. If you can handle all that torque and power. :thumbsup:

Can you say, "Race fuel, $5.00 a gallon"?

ovrrdrive, are you the on the FZ1OA list?

if there was a 490cc kit that was as reliable as the stock motor and WAS STOCK compression. i would do it. the power of a properly jetted wr450 can be a scarry at first. but im used to it now. even in very tight single track. all that extra power would be sweet on on the track too.

I have mine jetted to perfection and it almost rips my arms out of the sockets. :lol: I cant keep the front end down in the woods unless I am short shifting. I ride at the lower rpms for the most part. I cant imaging anyone running in the top rev ranges in eastern & midwest woods. The exception is desert type terrain and deep sand. Hell I am even scared of the YZ cam. I had it in for a month and took it out because it was going to plant me in a tree head on again (hurt once and scared the crap out of me the rest of the time) :awww: the way it was wheeling out of corners so hard under full gas. I honestly can say that the stock WR450 with mods is plenty fast for me. :thumbsup:

ovrrdrive, are you the on the FZ1OA list?

One and the same. :thumbsup:

I'm doing my homework until I get that damned FZ1 sold...

Just trying to pick a fight passin' time. :awww:

Can anyone help me in finding a big bore kit for my 03 WR450? Thanks, Dirtmizer.

Hi Dirt,

May I ask why you want a big bore kit. If your 03WR450 is bone stock meaning that it still has the throttle stop in it and the muffler insert, there are several free mods that you can do that will unlease ALOT of power from the motor.

Check out this website. It's for the WR250, but almost everything applies to the WR450 as well. http://www.thumperfaq.com

Hey, I was out of line to call it a crock to want more power. I have certainly been guilty of this on practically all of my machines. The one exception has been my WR450F after getting it uncorked and properly jetted. The versatility of this bike makes it practical for a wide variety of applications. Who am I to criticize another for wanting to modify for their uses. I apologize to the original poster. I admit, I am a hypocrit and got called on it. :thumbsup:

But as Indy states, the thing is just a handful "STOCK" in the woods or on a mx track(even on big outdoor tracks). When the best riders in the world are putting on heavier flywheels, something is up.

Supermotard, desert racing, dual sporting are definately places where you can always have a need for more power. Come to think of it, anybody got a link to that 490 kit? :awww:

hey you mention flywheel weights my bike bike is about matched to my size (6'4" 290lbs ) as far as hp and handling character,but iv'e had some stalling issues in tight uphill turns where slipping the clutch is difficult its even geared 13/52 so i was wondering if a little more flywheel might do the trick and how much more than stock can you go without too much drag?

6'4" 290lbs

Sounds like you're not just a "mountain man" but also a mountain of a man!! :thumbsup:

Maybe he is building a hill climb bike... Its not out of the ordinary to want more power... Two of my bro's just put big bore kits in their KTM 525 SX's for hill climbing in Trinity Co.

ovrrdrive, are you the on the FZ1OA list?

One and the same. :awww:

I'm doing my homework until I get that damned FZ1 sold...

Just trying to pick a fight passin' time. :thumbsup:

Yeah, I thought I smelled trouble... :lol:

Welcome to Thumpertalk (better late than never)

Can you say, "Race fuel, $5.00 a gallon"?

Nope, I run thier 13:1 kit on 93 octane no problem, it's not quite the same as a car, where the timing causes predetionation.

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