2008 WR450F with 2006 YZ suspension and cams

Full Akrapovic system for a 09 YZ450 Should bolt on the WR fine. $480 Shipped is very tempting.

http://www.ebay.com/...00b9cea&vxp=mtr

Coming from road racing for the last 10 years, I have used just about every exhaust manufacture out there and Akrapivic is hands down the highest quality exhaust that you can get. Leo Vince is a close second.

Yeah, that's a 'no returns accepted' sale, which means you'd better contact Akrapovic about absolute certainty of fit on the WR.

It doesn't take much to end up with a pipe you have to give away on ebay just to get rid of it......don't ask me how I know this....

So do that, and get back to us..... :rolleyes:

When you go to buy the Power Bowl 2 look around on the net, I got mine for around 160 shipped.

Yeah, I got 'a guy'..........

Edited by Krannie

great work, you answered my suspension dilemma! I was trying to figure out what I want to do with my stock 07 forks.. looks like the answer is the SSS swap with a revalve.

I am going to ask for a PBII when more fun money comes my way, I couldn't get rid of that slight bog on the street cracks either. Forks are the priority right now.

as for the exhaust, I have tried quite a few on the WR... the Leo Vince was definitely the nicest by a long shot. I regret selling it. I swapped for a Lexx mxe just for the trail saver super quiet tip (~88db) for the local secret stash trails. If I were to do it over again I would run the Leo Vince but fab a super quiet tip for it. Quality is very good in the Leo.

Yes, I am not an overall Leo Vince fan, but I have seen/ridden/heard then on YZ's and WR's and was very impressed.

SOMEBODY PLEASE BY MY FMF 4.1 Ti FOR CHEAP !!!

IT'S GOT NO DENTS!

Yeah, that's a 'no returns accepted' sale, which means you'd better contact Akrapovic about absolute certainty of fit on the WR.

It doesn't take much to end up with a pipe you have to give away on ebay just to get rid of it......don't ask me how I know this....

So do that, and get back to us..... :rolleyes:

Yeah, I got 'a guy'..........

wow that is a pretty good deal... and Akra is extremely nice...

I know for a fact that will bolt on.. I used to run an 09 yz450f full system. I would pick that bad boy up...

wow that is a pretty good deal... and Akra is extremely nice...

I know for a fact that will bolt on.. I used to run an 09 yz450f full system. I would pick that bad boy up...

REEEEAAALLLY ????

WHERE'S MY WALLET...

i JUST RODE IT!..at my little local track (spoiled).

I think I'm starting to figure out the suspension settings too.

Now that it handles better, it doesn't seem as fast..... More cams!

IMG_0582_zpsc045e8ce.jpg

Update # leventy-zillion:

Well, turns out there is NO accelerator pump linkage spring upgrade in the carb like the PO said there was.

I am going to start a picture thread on how to replace the linkage spring, how to inspect your apump system, and to upgrade with the R&D powerbowl, and how to quickly adjust the squirt.

Stay tuned.

The TPS is waaay out, and I will try to adjust it, in but past experiences I just end up unplugging it for the smoothest result.

I suppose the Dynatek is an alternative, but it will have to wait.

R&D Powerbowl II is on it's way. Just like the 2007's, the 2008 has terrible partial throttle steadiness on paved roads.

Something to do with the needle jet and gas frothing, I am told.

It only happens about 3 or 4 minutes into a steady throttle run. If you bounce the bike up and down, it goes away for a minute, and then comes back.

The PB Ii has always cured this in the past....

YZ suspension is still pretty far off. It's just fine for really fast fire roads and really slow technical, but the rough terrain above 3rd gear, it is not tracking the terrain closely enough.

I am going to back off the rear high-speed compression by 1/2 turn, and try again to get a balance of keeping the rear end up (more low speed compression) , and having the rear wheel still remain on the ground as much as possible.

The forks have so much stiction, they act like they have reduced travel. On the pavement, they don't even move, most of the time....making transitional rut-repairs a real fun time... and they don't even feel that stiff when you pump them.

Once you get going however, they do work very well. Very plush, very predictable. I have yet to take them on 45mph whoops.

FMF pipe is waaaay to loud.

A good 10db louder than the Dr D on my X. I pulled the can to re-fill it, and it was already filled.

I am shopping for a different pipe ( Leo Vince looks nice, or the Dr D).

*** THE FMF 4.1 Titanium slip-on will go up for sale, if anyone is interested. It's almost pristine in appearance. $ 180.00 !!

The cam's are GREAT. The bike is a rocket! The bottom end appears to be exactly the same as the stock cams, but let the rpms get up around 4500, and thing pulls HARD.

It's tons of fun to drift the thing around fire roads!

Don't like the GPS steering damper.

It only damps one way, which makes for feedback I am not used to, and I keep over compensating.

It will go up for sale too, as I don't want to have to re-think too much when jumping from bike to bike.

I had that problem with the KTM.

Completely different set of muscles to steer the KtM.....

Overall, it's all heading in the right direction: a bike that can be ridden very, very slow, over rocks and sand, and still JET up to speed, and handle the fairly rough stuff, without being a big fat Cadillac to do so.

That bike is looking good Krannie!! I am anxiously awaiting your writeup on the AP squirt and carb mods/tuning. On my '07 I used the JD kit with the O-ring mod and it runs great. There is also no surging at steady/constant speeds unlike my old 426. I have just been a little hesitant to mess with the AP because I don't want to make it worse. From what I understand, the Merge Racing spring is the permanent alternative to the O-ring mod? I should probablt throw one in next time I pull the carb. What are the benefits to the R&D Powerbowl II ? Thanks for sharing your project with us.

From what I understand, the Merge Racing spring is the permanent alternative to the O-ring mod? I should probablt throw one in next time I pull the carb. What are the benefits to the R&D Powerbowl II ? Thanks for sharing your project with us.

The o-ring mod merely pushes the apump linkage up close, so the slight delay is mostly eliminated.

But, it does not address on/off/on throttle issues, without ever completely closing the throttle....for that, the o-ring mod does nothing.

It cannot provide constant and increasing pressure that the spring provides, and keeps the apump totally in time with the throttle.

It really is a substantial difference with the leak jet, the spring, the proper short rivet diaphragm and long diaphragm spring, and then finally, timing the apump squirt.

The Powerbowl II is a 'cavitation eliminator'.

For some reason on the WR, the constant throttle issue is more pronounced.

On my CRF450X, KX450, KTM, etc, it was not a requirement, just a nice upgrade.

But on the WR, I consider it a requirement.

I can't explain how it solves the problem but I can tell you this: the power delivery becomes substantially more 'linear'.

What I mean by linear is, the position of the throttle always measures out the same about, each and every time.

So, you don't find your self 'over throttling' , just in case, in tough situations.

That, and the partial throttle at constant speed issues are noticeably reduced.

It's like the bog of the stock apump system....it doesn't seem that bad....you get used to it....until you eliminate it, and the bike is transformed, regarding how you can ride it.

How much was the '12 headlight? looking good

How much was the '12 headlight? looking good

bikebandit dot com

Full Akrapovic system for a 09 YZ450 Should bolt on the WR fine. $480 Shipped is very tempting.

http://www.ebay.com/...00b9cea&vxp=mtr

Coming from road racing for the last 10 years, I have used just about every exhaust manufacture out there and Akrapivic is hands down the highest quality exhaust that you can get. Leo Vince is a close second.

...only one problem....

We will NOT ship to any address within the state of California

Don't like the GPS steering damper.

It only damps one way, which makes for feedback I am not used to, and I keep over compensating.

It will go up for sale too, as I don't want to have to re-think too much when jumping from bike to bike.

I had that problem with the KTM.

Completely different set of muscles to steer the KtM.....

I think you've got that backwards. The GPR dampens in both directions. The Scotts does not dampen on the return. I agree on the GPR though. I have both and prefer the Scotts though both get the job done.

I think you've got that backwards. The GPR dampens in both directions. The Scotts does not dampen on the return. I agree on the GPR though. I have both and prefer the Scotts though both get the job done.

Yeah, you are right.

...only one problem....

We will NOT ship to any address within the state of California

I gave them a call and ended up buying one. I will PM you the info but they will ship it to you. Also I got it $40 cheaper.

By the time I sell my new OEM exhaust I should be into the new Akrapovic for around 250. :smirk:

Edited by gcally

Good deal on a full Leo Vince but it is the older design with the smaller 38 mm header.

299 shipped.

http://www.ebay.com/...415c92c&vxp=mtr

Where do you see that there are other header sizes? Certainly not on the LV site....

I think any other pipe version is for the FI models?

Edited by Krannie

It really is a substantial difference with the leak jet, the spring, the proper short rivet diaphragm and long diaphragm spring, and then finally, timing the apump squirt.

Are you going to use longer AC Pump diaphragm spring that comes with R&D Power Bowl or some other one?

What would be the advantage to using the diaphragm with a smaller post compared to the Yamaha one that is 1 mm longer? My initial thought is to give the R&D adjustable leak jet more range of adjustability.

Are you going to mess with the ACV (air cut valve)? From the research I did some people disable the ACV to make air fuel screw adjustments and jetting easier/more accurate at lower rpms.

Are you going to use longer AC Pump diaphragm spring that comes with R&D Power Bowl or some other one?

What would be the advantage to using the diaphragm with a smaller post compared to the Yamaha one that is 1 mm longer? My initial thought is to give the R&D adjustable leak jet more range of adjustability.

Are you going to mess with the ACV (air cut valve)? From the research I did some people disable the ACV to make air fuel screw adjustments and jetting easier/more accurate at lower rpms.

Long spring, short rivet diaphragm (crf450r)

The short rivet gives you more squirt volume (duration and distance) depending on the leak jet.

With the stock intake and exhaust and header, it's not needed.

The ACV valve is already disabled. It sucks. Well, actually it blows.

Rear wheel hop test: re-set the high speed out .75 turns, and went in on the low speed.

I was trying to get the rear end from jumping out when hitting a pot hole in the middle of a sweeper corner.

I worked. The rear wheels stays glued to the ground.

Well, the aircut valve had already been modified, but the apump linkage was NOT.

I decided to go with the R&D powerbowl II, which comes with an upgraded bowl, apump system, apump diapragm spring, apump linkage spring.

I've used these on a few bikes prior, and they work fantastic.

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