STOCK 04 450f needs your help

Okay Guys..I need your help here. I have a bone stock 04 yz450f that I have raced for two years. I am finally at the point where I want to throw some mods at it and I have information overloaded myself. I am 38 yrs old, 6ft 4in and 210 lbs. I run in the plus 30 amateur classes although I would classify myself as a top 10 novice. I want an exhaust system and a flywheel weight that will mellow out "the hit" a bit. Can you give me any real world advice on what you think would be a good combination? Thank you in advance for your feedback!

I would try a 47T rear sprocket as the first thing. It helped on my '03 and it was cheap (compared to a pipe or flywheel weight)

Thanks John..I ordered a Renthal chain and sprocket set yesterday and did exactly what you suggested..47 as opposed to 48. I appreciate your input!

I just put a Rev Max ignition on my 05 YZ-450 as it was a little lazy on bottom. According to greyracer Yamaha mellowed out the 04 motor by changing the ignition curve. It seems like the curve on the ignition I put on must be in between the 2 years as it was a pretty nice improvement but not to much. Was able to do some jumps from the inside I would have to run at before. Maybe it would mellow out the 04 as I hear they hit hard. Also like my DR.D exhaust, well made and much better than the power of the stock. Since you are so tall it may not help as much but offset clamps really help the cornering on these bikes.

A Dr.D 8oz flywheel is $90, while a good rear sprocket runs $60. Dollar for dollar, the flywheel will do more for you than the sprocket.

A full FMF with a Power Bomb will smooth over the spike in the power curve that the bike has at around 7000, but won't make it any less sudden off the bottom. A Dr.D will work well also.

But if you are at the point in your development that you say, your best bet may be to sell it an get into an '06 or '07. Nothing you do to the bike will make you as fast as you'll be on the new one.

Gray and MX thank you for your input...I am going to wait another year to get a new steed so it looks like the pipe and flywheel weight along with dropping a tooth on the rear is the hot set up. I actually really love the power curve on this bike but I guess I'm not getting any younger...its kinda like realizing you would rather have heated seats in your truck as opposed to the killer stereo!

...its kinda like realizing you would rather have heated seats in your truck as opposed to the killer stereo!

Yah those seats are nice aren't they.

Okay Guys..I need your help here. I have a bone stock 04 yz450f that I have raced for two years. I am finally at the point where I want to throw some mods at it and I have information overloaded myself. I am 38 yrs old, 6ft 4in and 210 lbs. I run in the plus 30 amateur classes although I would classify myself as a top 10 novice. I want an exhaust system and a flywheel weight that will mellow out "the hit" a bit. Can you give me any real world advice on what you think would be a good combination? Thank you in advance for your feedback!

Hey didn't the 04 come with the GYTR 5oz flywheel weight? If it is still to hard hitting go with a 8-12oz....Although I luv my 03 with the 5oz...

I will tell you to - that at your weight you should consider the suspension as a upgrade if this is a bone stock suspended 04...a revalve and stiffer springs will help you enjoy the hit much more as I am sure it is diving at both ends way too much when accelerating and braking...I bet braking bumps are painful too. Aslo any aftermkt pipe will add more hit/more power than the stock header/cannister:thumbsup:

My favorite set up was 50t in the rear and a 13oz stealthy weight. I could put it in 3rd and with a bit of clutch could run it like an automatic and only need 4th and 2nd here and there. Sounds odd and maybe it is, but the 50t allowed more off the bottom and the weight knock the edge off the hit (made it feel a whole shit load like my 426 was but stronger). Only problem is that this made for a bike that front to back position was critical, it could pull the front in third just off idle if you were slid back a bit on the seat.

just my thoughts.

Does the flywheel weight help with stalling the motor? I don't wan't to tame down the power much but would love it to not stall so easy, I have killed my motor when going slow over jumps more than once.

Yes, it does. You won't really notice that the engine feels less snappy, either. What you will notice is that you will feel like the bike has better traction more often, and that it seems less likely to vaporize the rear tire when you break into the throttle a little.

Thanks to all of you for your help. I ordered a DR.D pipe and 8oz flywheel weight today. I will let you know how it is after I get everything on and go for a few blasts. I'm actually pretty happy with the suspension...it feels pretty comfortable for me when I am back down to my riding weight of 198..only 12 pounds left to lose, damn those holidays!

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