Sign in to follow this  
Followers 0
nickt916

just picked up 07 WR450 how does it compare to YZ450

27 posts in this topic

I just recently sold my yz250f, loved the bike, but hated that it was a red sticker and couldnt ride everywhere.

I just picked up a 07 WR450 for $4,000 it has about 30 hour on it

(by the way does the speedometer supposed to show miles on the bike since day one? because i only saw trip A and B and thats all)

The guy had suspension work done on it for a 200lbs rider, just right for me, also he removed the smog stuff, and got it jetted, and did the throttle mod, gray wire mod or something of that? and not sure what else.

Im curious, it sounds like a little dinky moped with that stock exhaust , if i can put a Yz450 muffler on it will it free up a bit hp and i would need to rejet it again, if i remember correctly it its 1.5 turn with 45 and 170? id have to double check.

My other question is, the bike is like 250lbs YZ450 is like 220, battery started headlight, what else gives is so much weight?? The rear wheel is 18 so the tire is bigger, would the bigger fater tire add more weight compared to a 19" YZ wheel? because i was thinking about going 19 and new wheels like black and new tires... whats the reason the WR has 18" and YZ 19"??

Id like to make the bike as light as possible and sound like a YZ450, my yz250f was all stock and this thing sounds like crap compared to this wr exhaust, sounds so restrictive (im assuming it comes with a mesh screen fire arrestor being stock)

man thats alot of questions for one thread, sowi :ride:

Share this post


Link to post
Share on other sites

the mileage can be reset at any time,

the 18" wheel is for more sidewall which means more shock absorbsion and better traction when trail riding - keep the 18"

a YZ or after market muffler will give you more power and the sound you're looking for - make sure it has a spark arrestor

what kind of riding do you do?, I love my '06 for trail riding and the extra wieght is an easy trade for the headlight and the button...........

have fun, you will love your WR:ride:

Share this post


Link to post
Share on other sites

My 07 was dead until i re jetted added yz throttle stop and got a FMF factory 4.1 slip on with twin air filter and ais removed! My Buddy's `06 yz 450 can`t keep up with the wr? :mad: Maybe something is wrong with his bike!! I love this bike :ride:;):p:rant:

DSC00013.jpg

Share this post


Link to post
Share on other sites

YZ exhaust bolts right on. Make sure you go for the full system. Wakes the bottom end up and it will sound like a thumper now.

I went with the 08 YZ exhaust on my 07. That and an EBATT replacing my stock battery and I saved around 6lbs anyways. Only 24 to go ;)

It sure is nice having that e-button for stalls and gnarly places in the woods though :ride:

Share this post


Link to post
Share on other sites
YZ exhaust bolts right on. Make sure you go for the full system.

just to add.

the stock WR head pipe is a 38mm diameter pipe. where the outlet of a 07 YZ head pipe is about 45mm, although I beleave most of the pipe is 43mm diameter. the 08 YZ head pipe necks down and has a smaller outlet(41mm), so the 08 head pipe is only 3mm less of a clog then the WR head pipe.

the confusing part is that thease mufflers all have a 45mm inlet, and the difference is taken up with a gasket.

that being said, I'm still running my after market slip-on with the 38mm WR head pipe. and just the slip on was a big improvment over the stock muffler with a GYTR tip.

Share this post


Link to post
Share on other sites
also he removed the smog stuff

depending on where you ride, you are going to need the reinstall the AIS. the

AIS...other then weighing over a pound , and being in the way for valve checks and the exhuast poping... its not realy that bad:bonk: . a lot of people throw it away, which is a mistake if you live in kalifornia.

Share this post


Link to post
Share on other sites
Ni-cads. its a smaller battery pack made of cells. lighter but less durable.

www.ebattonline.com

I don't know about less durable. I've been running one all season, and I race most weekends (except now in the heat of the summer ) without an issue.

They also hold a better charge for lot's of strong starts.

Share this post


Link to post
Share on other sites
Ni-cads. its a smaller battery pack made of cells. lighter but less durable.

www.ebattonline.com

just to add.

the stock WR head pipe is a 38mm diameter pipe. where the outlet of a 07 YZ head pipe is about 45mm, although I beleave most of the pipe is 43mm diameter. the 08 YZ head pipe necks down and has a smaller outlet(41mm), so the 08 head pipe is only 3mm less of a clog then the WR head pipe.

the confusing part is that thease mufflers all have a 45mm inlet, and the difference is taken up with a gasket.

that being said, I'm still running my after market slip-on with the 38mm WR head pipe. and just the slip on was a big improvment over the stock muffler with a GYTR tip.

I haven't measured but I can tell you my 08 YZ header is a lot more than 3mm bigger than my 07 stock header.

Share this post


Link to post
Share on other sites
I haven't measured but I can tell you my 08 YZ header is a lot more than 3mm bigger than my 07 stock header.

you sould measure it. the document I have on the gasket says its a 45mm OD and 41.6mm ID. thus teh outlet of the pipe is 41.6mm.

The pipe looks like a fatty but it necks down to a smaller diameter just before the heat sheild ends. basically has a 41mm pipe weleded to the end.on the 2007 right at that weld is where it steps up to around 45mm. I almost got an 08 header, but did my resaerch and decided against it.

see the weld on the picture of a 2008 pipe below.

208d_1.JPG

in contrast the WR head pipe is about 38mm thru its entire length.

:ride:

Share this post


Link to post
Share on other sites

im a bit confused with the YZ piping, so some years are bigger and some are smaller and some will fit and some wont? would any 06-08 header and full pipe fit my 07 WR, and i would just need to buy a gasket for a YZ450?

since the bike doesnt have smog stuff on it, and the gray wire was cut (im not sure what that is yet) and if i put on the YZ450 full pipe can i just use same jetting the YZ450 has stock?

Share this post


Link to post
Share on other sites
im a bit confused with the YZ piping, so some years are bigger and some are smaller and some will fit and some wont? would any 06-08 header and full pipe fit my 07 WR, and i would just need to buy a gasket for a YZ450?

since the bike doesnt have smog stuff on it, and the gray wire was cut (im not sure what that is yet) and if i put on the YZ450 full pipe can i just use same jetting the YZ450 has stock?

one step at a time. I wouldn't worry about it. but if you are going to coble together parts, you are going to have to figure it out. if you just buy an after market system then its all figured out for you.

the point I tried to make is that you can get more bottom end by ditching the stock muffler. when you do get a new muffler, you'll have to decide if you are getting a complete exhuast or a slip on. one downside to a slipon is that the stock WR heap pipe is really tiny.

If you buy a FMF Q4 slipon. then its easy... you just buy the slipon now and buy their head pipe later(the YZ and WR use the same FMF head pipe). the Q4 is very popluar. the DRD is a very popular full exhaust.

Stock YZ exhuast would also be good. but some years are better then others and you'll have to come up with a spark arestor. but all the YZ systems will be better then the WR system.

I got a leovince X3 slip on. which is very nice, but they do not have a solution for the 38mm Head pipe. so I'm forced to figure it out. I found that with the right gasket I could adapt any YZ head pipe to fit my X3.

Share this post


Link to post
Share on other sites

that's basically what I want is the yz 06-08 exhaust , then put spark arrestor on it. So the head pipe on 06yz and 07wr is same? I can just get the muffler and be good to go? Or would I have to rejet for the yz pipe?

Share this post


Link to post
Share on other sites
you sould measure it. the document I have on the gasket says its a 45mm OD and 41.6mm ID. thus teh outlet of the pipe is 41.6mm.

The pipe looks like a fatty but it necks down to a smaller diameter just before the heat sheild ends. basically has a 41mm pipe weleded to the end.on the 2007 right at that weld is where it steps up to around 45mm. I almost got an 08 header, but did my resaerch and decided against it.

see the weld on the picture of a 2008 pipe below.

208d_1.JPG

in contrast the WR head pipe is about 38mm thru its entire length.

:ride:

It definately steps down as your photo shows, but I still find it hard to believe to 41mm ;)

I will check one of these days

It still breathes a hell of alot better than the stock header

Share this post


Link to post
Share on other sites
that's basically what I want is the yz 06-08 exhaust , then put spark arrestor on it. So the head pipe on 06yz and 07wr is same? I can just get the muffler and be good to go? Or would I have to rejet for the yz pipe?

Headpipe will bolt right on as will the muffler.

Have you rejetted already ?

I had GYTR jetting which was running a little rich with the stock exhaust but was liveable.

Definately had to lean it out with the YZ exhaust.

Share this post


Link to post
Share on other sites
that's basically what I want is the yz 06-08 exhaust , then put spark arrestor on it. So the head pipe on 06yz and 07wr is same? I can just get the muffler and be good to go? Or would I have to rejet for the yz pipe?

so, if you want to coble things together.... you'll have to do your homework.

Share this post


Link to post
Share on other sites
It definately steps down as your photo shows, but I still find it hard to believe to 41mm :ride:

I will check one of these days

It still breathes a hell of alot better than the stock header

OK, I still entertain the idea of getting an 08 head pipe. ;) I've got the partnumber for the gasket I need. I just need to find a good price on the head pipe.

the MX mags all say that the 08yz exhaust was designed to make tractible power. and be quite, I'm sure that is 2 things I want for my trail bike. part of the issue for me is that I got to stay under 96db.

and I don't realy want to deal with a bike that hits to hard down low when when it gets muddy.

Share this post


Link to post
Share on other sites

right now the bike was jetted because smog stuff was removed. I'm just asking if the 06-08 yz pipe and yz header header will work on a 07-08 wr or the wr header same as yz?

I'm at work for like 12 hours, my phone is the only Internet access, very hard to do these type of researches

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0