My 2008 Yz 450f Review

[djtroy]

Ok this is a true honest opinion of what I thought of the 2008 yz 450f. I am a proud owner of a 2006 yz450f also.

I started it up and ran it through a few heat cycles then I decided to take it for a few runs up the road. Right away I knoticed it backfired on decel and it had a really rough feel to it. It was lurching forward and didnt seem to be jetted correctly at all. After I put it on the truck it was time to head to the track.....

Right away I noticed how quiet it seemed. It was so quiet it gave you the sense it wasnt fast. Wait a minute IT WASNT FAST AT ALL. I quickkly realized the motor had NO BOTTOM END POWER at all. It seemed like it pulled ok when it was in the higher RPM ranges, but I wasnt too sure because again the bike was so quiet you couldnt tell. I would honestly say my 2006 still had much more power and a better hit then this 08 especially in the low rpm ranges. I was also having to shift this bike constantly to make it work. I really need to get this problem figured out. Im sure jetting and some other mods could bring the botton back from the dead and some more power on top would be good too. I think possibly a bigger rear sproket is in order also.

Well that was what I thought of the motor and let me tell you what I thought about the handling cornering and suspension....

AMAZING :applause:

As much as the motor totally sucked, the cornering from the 2006-2007 models was astounding. It turned into tight inside lines, you could sit on the edge of the seat and let it hang out and if it got sideways you could countersteer I and feel totally in control. I was able to put the front end anywhere I wanted with 100% confidence. It cornered like my old 125 use to. The suspension was right on par with the 2006-07 stuff if not better. Even though I felt the motor was slowing me down I know I was turning faster laps on this new 08 becasuse my 06 does not corner at all.

Does anyone know how to make this motor come to life? Its so electric sounding, has bad jetting, its hard to start and it does not have any power.

I have not read any reviews so I not repeating stuff that has already been said. I am telling you what I thought of this 2008 yz 450f today.

Overall I would give up a powerful motor for good cornering capabilites because I know someone can help me get this motor working and this bike will be perfect.

[TuningFork426]

ROFL your 2006 doesn't corner?

[450GN]

nice review! im sure there will be many remedies for the low end...

jetting... pipe... and accelerator pump cover should really wake things up i would think

[djtroy]

ROFL your 2006 doesn't corner?

Ya my 2006 DOES NOT CORNER!!!!!

[djtroy]

nice review! im sure there will be many remedies for the low end...

jetting... pipe... and accelerator pump cover should really wake things up i would think

Yes those items woke my 2006 up BIG TIME.

[Huckster]

Zipty carb mod? Langston rode the '08 this weekend and won the 2nd moto. He made the comment that the '08 turns better for him. What did they do to the '08 that would make it turn better than my '07? If its real and true, it would make me consider buying a '08 because my '07 does not turn that well either compared to the yellow and red bikes, IMHO>

[CrusRuss]

Its probably just not jetting right. Also you need to break in the motor as well. I doubt they would release a bike that had noticably less power.

Can you compare the cornering to a new (06/07) RMZ? I have an 06 CRF and RMZ and the RMZ is even hands down better than the honda in corners.

[Ga426owner]

Ok this is a true honest opinion of what I thought of the 2008 yz 450f. I am a proud owner of a 2006 yz450f also.

I started it up and ran it through a few heat cycles then I decided to take it for a few runs up the road. Right away I knoticed it backfired on decel and it had a really rough feel to it. It was lurching forward and didnt seem to be jetted correctly at all. After I put it on the truck it was time to head to the track.....

Right away I noticed how quiet it seemed. It was so quiet it gave you the sense it wasnt fast. Wait a minute IT WASNT FAST AT ALL. I quickkly realized the motor had NO BOTTOM END POWER at all. It seemed like it pulled ok when it was in the higher RPM ranges, but I wasnt too sure because again the bike was so quiet you couldnt tell. I would honestly say my 2006 still had much more power and a better hit then this 08 especially in the low rpm ranges. I was also having to shift this bike constantly to make it work. I really need to get this problem figured out. Im sure jetting and some other mods could bring the botton back from the dead and some more power on top would be good too. I think possibly a bigger rear sproket is in order also.

Well that was what I thought of the motor and let me tell you what I thought about the handling cornering and suspension....

AMAZING :applause:

As much as the motor totally sucked, the cornering from the 2006-2007 models was astounding. It turned into tight inside lines, you could sit on the edge of the seat and let it hang out and if it got sideways you could countersteer I and feel totally in control. I was able to put the front end anywhere I wanted with 100% confidence. It cornered like my old 125 use to. The suspension was right on par with the 2006-07 stuff if not better. Even though I felt the motor was slowing me down I know I was turning faster laps on this new 08 becasuse my 06 does not corner at all.

Does anyone know how to make this motor come to life? Its so electric sounding, has bad jetting, its hard to start and it does not have any power.

I have not read any reviews so I not repeating stuff that has already been said. I am telling you what I thought of this 2008 yz 450f today.

Overall I would give up a powerful motor for good cornering capabilites because I know someone can help me get this motor working and this bike will be perfect.

a White Bros Alum Pro pipe and Zipty carb mod will wake it up.....

Originally Posted by TuningFork426

ROFL your 2006 doesn't corner?

Ya my 2006 DOES NOT CORNER!!!!!

wahhhhhhhh wahhhhhhhhhh wahhhhhhhhh

[Huckster]

Its probably just not jetting right. Also you need to break in the motor as well. I doubt they would release a bike that had noticably less power.

Can you compare the cornering to a new (06/07) RMZ? I have an 06 CRF and RMZ and the RMZ is even hands down better than the honda in corners.

I came off a RMZ. Just strictly talking turning,the Yamaha does not even come close to the Suzuki. The Yamaha is an awesome bike and is better in every other facet IMHO, except turning. It will not carve like the suzuki no matter what I try. With that said, I have learned to live with the way it turns and I do like it better than the suzuki as an overall package.

[Numba68]

I dont think that a pipe will give you near as much of a diffrence as proper jetting.

[djtroy]

I agree I am looking for jetting specs because this will really help. The pipe will make it "feel faster" beacause even though the short silencer is cool its too quiet for me. I know the noise has been an issue but trust me it is gonna take siome getting use to.

This bike will definately get bad reviews because of these things, trust me.

I would never say its a bad bike but it needs a little tweaking for sure.

As far as the cornering its great I can tell you that and if the motor can improve it will be 10x better to ride than the 06 / 7's if you hate how they corner.

Let me know if anyone has jetting that works. I am just above sea level, hot and humid in the Carolinas.

Im sure its running lean. I am going to get an air screw for it and try that but I would love to do the whole thing. Perhaps Zip ty can tweak it already. Maybe Ill send it away to them.

[Justin89]

Did you follow the proper break in instructions?

[Camrose Cycle]

WHAT?!?! I think your dreaming dude! I just got my 08 450f about a week ago and just raced it this weekend. THis bike is by no means lacking bottem to mid range power. THis bike pulls hard all the way through without any hiccups. I race 250 intermediate and this weekend i pulled 2 holeshots out of three starts on this stock 450. THe bike does sound nice and quiet which might make you feel like its not pulling as hard, but dont let that fool you. IT was the same way with the 07 250f, very decieving.

[djtroy]

WHAT?!?! I think your dreaming dude! I just got my 08 450f about a week ago and just raced it this weekend. THis bike is by no means lacking bottem to mid range power. THis bike pulls hard all the way through without any hiccups. I race 250 intermediate and this weekend i pulled 2 holeshots out of three starts on this stock 450. THe bike does sound nice and quiet which might make you feel like its not pulling as hard, but dont let that fool you. IT was the same way with the 07 250f, very decieving.

Its slow on the bottom PERIOD. I have been racing motocross all my life (25 years) and I work at a Yamaha dealership now. I am telling you what I think. You might feel different and like I said I have not read any reviews so other people might feel different than I do. I have never wrote a review on a bike nor do I feel the need to.

I did feel I had to go on the boards with this bike because it was definately not where it needs to be in terms of jetting and power.

I know there are things holding this bike back. If you want to leave your stock thats fine but I know this bikes motor is no where near as good as my perfectly jetted (thanks thumpertalk) 2006 450f.

[Camrose Cycle]

I do not agree with you at all that this bike is slow on the bottom end whatsoever. Ya ya - Of course it could be hopped up a bit to run better, any bike could be. THe point is in stock form this bike is by no means lacking power compared to other 450's. I by no means am saying your other bike doesnt run better considering it was jetted for whatever application your running in; but apples to apples i would highly doubt that when both were jetted properly that your 04 would feel or have more power.

[djtroy]

I do not agree with you at all that this bike is slow on the bottom end whatsoever. Ya ya - Of course it could be hopped up a bit to run better, any bike could be. THe point is in stock form this bike is by no means lacking power compared to other 450's. I by no means am saying your other bike doesnt run better considering it was jetted for whatever application your running in; but apples to apples i would highly doubt that when both were jetted properly that your 04 would feel or have more power.

I have an 06 and Im hoping your right. "when jetted correctly" Im hoping my 08 will make better power than my 06 so I can compre apples to apples and not apples to oranges.

[Ga426owner]

Correct jetting will make it run better - but jetting from factory is not so far off that it is robbing tremendous power...it is probably slighty lean as the 06-07s are

A WB pipe will give you more lowend power period end. That is what it is designed to do. How can you substantiate a Aftermkt pipe can not give any more power.....I am all ears on this one...

That stock shorty muffler is probably cool and quiet but I would say restrictive also.

A larger sprocket may help, but you determine how much shifting you want to do first

The Zipty mod is another way of increasing low end hit by tuning the FCR to perform like it is designed. Right now stock it works but is not tuned to its capability for ideal squirt duration, leakjet or AP fuel flow:thumbsup:

[Linc007]

This weekend I took out a brand new 07 yz250f,I was stunned at how it sucked for power in the bottom end,I was pissed.So I rejetted and bingo,,,,brought it back to life,so I think that with some jetting and break in it,the 08 450 will be a different bike.

[250f canuck]

I think that the quiet pipe is something that we will need to get use to riding with and tuning around. I did run my stock WR muffler open and loud for a little while and loved the power, but eventually I would need to pass sound check somewhere. I made an insert for it and imediatly the bottem end started hurting for power. I've done a bit of tweaking to the jetting (thank you TT:thumbsup: ) and my power is back and so is 90% of the response. A few leak jet changes should fix that also.

IMO jetting is your issue.

[djtroy]

Now all I need is someone to tell me what works for them. I guess the bike is too new so I will have to be the guinea pig on this one.