08 450 power solution?


11 replies to this topic
  • new450

Posted February 02, 2009 - 12:38 PM

#1

I'm considering buying an '08 YZ450 as I can get a screaming deal on one. I do however, have a few reservations: 1.Can the "smooth power" I've read so much about be upped considerably and easily (IE: pipe?) I'm afraid it'll seem too tame since I'm used to the CRF engine and really like those characteristics. I want lots of low, mid, and a great top-end too (I want it ALL!)
2. I've also read there is a "push" in the turns and a tendency to stand up. Is it really that bad?
3.MXA reports headset cracking problems due to cold welding at the factory - is this really an issue for the average Joe?

In case you think I'm just bagging on Yamaha's, I can assure you I'm not. I love the suspension (rode a 250F once with the SSS Kayaba's) and admire the reliability of the bikes. I think I've just over-saturated myself with magazine articles lately.

Thanks

  • KAS

Posted February 02, 2009 - 01:30 PM

#2

The stock muffler chokes them up quite a bit.

I've also heard you can install an '06 exhaust cam for more pep.

I haven't heard of or experienced any frame cracking.

Can't say much about the cornering. I think mine handles just fine.

  • Wiz636

Posted February 02, 2009 - 03:16 PM

#3

I think I've just over-saturated myself with magazine articles lately.


Sounds like it. The '06 had a tendency to push but Yamaha fixed it in 07 and further fine tuned the geometry for '08. In spite of this, I bet the rags will write about the 'YZ450 push' for the next three or four years. :)

Sometimes I wonder if they just write the article and then go take a few pics of a so called 'test rider' throwing a whip on it and call it good.

For the power, throw a Dubach exhaust on it and you will never look back.

  • grayracer513

Posted February 02, 2009 - 04:18 PM

#4

It's all a matter of chassis philosophy. The YZ does have a tendency to understeer on corner entry. But because of that, it has a tendency be very precise when leaving the same corner under power, and does NOT have a tendency to oversteer on exit, or leave you sitting on the ground. It bites, accelerates, and goes where you point it. But nobody mentions that.

Proper setup and rider technique can mitigate the understeer. Does this bike look like it's pushing?:

Posted Image

  • rjcook450

Posted February 02, 2009 - 04:21 PM

#5

I have an 08 yz450f, first thing i did was follow dirtbike mags. advice.
1. replace stock exhaust, i went with a full Ti drd setup
2. replace rear sprocket with a 50 tooth (stock is 49) helps to tighten up gear ratio make bike more snapy
Other things they recommened is adjusting fork tube height to help with front end push, i do not have any problem with front end so they are very picky or i'm not riding fast enough.
With pipe and rear sprocket change it has more than enough power to do waht ever you want and is very crisp,snaps hard when throttle is hammered, i have riden a stock 08crf450 of my buddies and we both perfered the yz, he has more years riding than i and it wasnt the power difference for him it was the suspension, which i agree with you is very very good.

  • grayracer513

Posted February 02, 2009 - 04:44 PM

#6

... i do not have any problem with front end so they are very picky or i'm not riding fast enough.

I don't know how fast you are, but the aluminum YZ450 is VERY "picky", or sensitive, if you will, to what seem like very minor changes in set up. Pulling the forks up, raising the hand position and moving it forward, cutting the sag by 5mm, moving forward an inch, all these bring far more noticeable results than you would think they would.

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  • rjcook450

Posted February 02, 2009 - 05:39 PM

#7

not as fast as most, but fast enough to win summer series Vet championship at local track last year (bragging a little), i do have my sag set lower than the normal 100mm. maybe i'm more forgiving than the bike, i might look into some adjustments, im sure they would make a difference, but than again i might just spend that time riding instead.:)

  • Wes Woodin

Posted February 02, 2009 - 07:16 PM

#8

I'm considering buying an '08 YZ450 as I can get a screaming deal on one. I do however, have a few reservations: 1.Can the "smooth power" I've read so much about be upped considerably and easily (IE: pipe?) I'm afraid it'll seem too tame since I'm used to the CRF engine and really like those characteristics. I want lots of low, mid, and a great top-end too (I want it ALL!)
2. I've also read there is a "push" in the turns and a tendency to stand up. Is it really that bad?
3.MXA reports headset cracking problems due to cold welding at the factory - is this really an issue for the average Joe?

In case you think I'm just bagging on Yamaha's, I can assure you I'm not. I love the suspension (rode a 250F once with the SSS Kayaba's) and admire the reliability of the bikes. I think I've just over-saturated myself with magazine articles lately.

Thanks

Throw on a Dr. D pipe and an R&D powerbowl and hold on. Most people can't ride them to their full potential. Go up one more tooth on the rear sprocket too..

  • grayracer513

Posted February 02, 2009 - 09:11 PM

#9

Don't fall for the Power Bowl. The only thing it does is provide an adjustable leak jet, which may be convenient if and while you sort out the leak jet size, but otherwise, it's useless bling. If you want an adjustable leak jet for some reason, the ALJ pump cover from accomplishes the same thing for half the price or so.

  • Family Man

Posted February 02, 2009 - 10:00 PM

#10

Probably the fastest guy Ive ever seen at the track was ridding on the stock 08, exhaust included. National level Mx rider. An aftermarket exaust will add More power to your bike. But after seeing the stock system blow everyone off at the track, I'm convinced the stock system can blow everyone off at the track. Its the rider. However, he may be capable of going faster on an aftermarket pipe!?

  • honda907

Posted February 03, 2009 - 04:49 PM

#11

I just got a 09 450 YZ a couple of weeks ago. Man , it doesn't need a thing. Actually, I got a new Dr.D pipe, radiator lowering kit(have to use the pipe) and a hour meter. I thought the bike ran better with the stock pipe. No lie!! It was indoors, but it ran good with the stock pipe. Turning was better than a CRF, and it had a very firm, precise ride in the suspension department (after about an hour of break-in). The new pipe was loud, and the response was a little boggy, but I didn't rejet either. I think it ran "smoother with the stock pipe. I know by my age I look like I may be old, But I still run 5-8 in the 250 B class ( out of 30) and I think this is the best bike I ever rode. I have had more than 40 bikes too ( after 35 years of racing)!

My advise, ride it stock. It is that good. I should not have listened to people on here and the magazines about the power. I think the bike flat out rips. Maybe at Southwick I can use the power, but local hard pack, the stock pipe is better. Just look at the Schoolboy class on 250f's. Heck they go about as fast as you can go , and they are about 15 horses down on 450's, yet in our area, the usually are the fastest class(or darn close to it).

  • harrperf

Posted February 03, 2009 - 08:44 PM

#12

I agree with almost everything said in this thread!

To answer the question though...the yami can run like a scalded ape with an exhaust jetted correctly, if you want an older model cam (not necessary...) and an vortex ignition will really wake that sucker up.

Honestly, just and exhaust and ignition and the bike probably is faster than any of the other bikes with similar mods....it really responds well that those mods. The head on the yami 450 is designed very well, and in stock form provides excellent shape and cross sections IMHO...

If you were to take it a step further, and bump the compression to say 13:1 with aforementioned mods, you would be on a bike more than capable (and likely found) at an outdoor nat....





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