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rcmxracing

'09 Rumors

36 posts in this topic

I've been googling rumors for 2009 bikes, especially the Yam 450...well TT keeps coming up, but when are we going to get some REAL info on the '09's on the web?! I'm back to a YZ250 2 stroke until I find out what's going on with the 09's. I never came to terms with my 2006 450 Yam - selling it. The front end really bugged me. Honestly I'm not sure if it's a complaint about 450 weight in general or just the '06 Yam frame. I am faster on my 2 stroke and faster on a 250F...at least the '08 KX250F I just rode. I can drive either of these bikes into corners further, and get on the gas sooner and if I make a mistake I can correct. I used to laugh about the idea of a 350cc 4pop but am considering a big bore 250F. The weight of a 450 screws up my cornering ability (races are won in the corners!). If I could have a 10lb lighter 450 I' would gladly take the horsepower. ..but I don't see that happening anytime soon.

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If your racing or been riding long enough you will find out that HP doesn't always transfer to faster lap times. In fact I've seen guys take there motors & have them built to the hilt & end up turning slower lap times. It takes a huge amount of skill to ride high HP bikes fast around a track that has corners. A lot of the 450 guys just point & shoot... in other words park it in the turn & power out WFO to the next turn. But there's nothing like having all that power it can be so much fun that you don't even care about lap times.

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so no plastic change or efi? thatd be nice to be able to keep my bike for another season then have all the changes happen in 2010

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Well that is a huge disappointment....I was hoping Yamaha would stick to the normal 3yr life cycle plan and come out with a spanking brand new 450 for 09. My wife may like this news because as of now I will still stay on my 06 until 2010....no need for less power and a new swingarm :thumbsup:

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That doesn't suprise me too much as I've been told for a while now that FI wouldn't be on the YZ450 until 2010 but that the new model will have a new chassis and possibly the carbon fiber airbox and subframe. I'd rather that they took their time and got it right than rush something out like suzuki. Maybe their working on port injection, that would really make a difference. I highly doubt that though.

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Maybe their working on port injection, that would really make a difference. I highly doubt that though.
Port injection works better than throttle body injection in cars because it reduces the distance traveled by the fuel through the intake manifold and eliminates fuel suspension issues. In a typical motorcycle engine, there is no functional difference between fuel injected at the throttle body, and an injector placed perhaps an inch closer to the valve in the port.

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I heard back in 06' that yamaha was testing a four valve system similar to the street bike or somthing. From what I was told they were hoping to get more power out it vs the 5 valve. In jumping back and fourth between my bike and my friends honda I don't feel any hp difference other than maybe where it hits. Who knows, maybe everybody will have a 4 valve system.

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Ron Hamp would tell you that it is definitely harder to get power out of a YZF head than a typical 4 valve. The '06 head was a huge improvement, but still a handicap in terms of cranking out raw numbers. The CRF you rode doesn't really have much more power, if any, than the YZF as built, but the engine does have more potential in the current form.

The new WR250X and WR250R models have 4 valve heads.

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I guarantee that Yamaha has done testing with 4 valve heads, 3 valve heads, and stuff we dont even know about. There are R&D facilities where they are testing designs that we dont even know exist. Looks like none of that type of trickery will make it to the '09. I guess '10 is a good round number for a new bike with changes.

I guess I can show my '06 a little love and wait for that one. Not enough of a change for me to dump a bike that I am competitive on.

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Notice the new 09 preproduction #12 Yami 450 pic with black clutch and ignition covers....then notice after 1 ride at the wash station...they are completely trashed....You would have thought more paint engineering would have been emphasized for 09 than 08....NOT

The hondas sure look unreal...the suzuki 's look unobtainium and the kawis look the same

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Ron Hamp would tell you that it is definitely harder to get power out of a YZF head than a typical 4 valve. The '06 head was a huge improvement, but still a handicap in terms of cranking out raw numbers. The CRF you rode doesn't really have much more power, if any, than the YZF as built, but the engine does have more potential in the current form.

The new WR250X and WR250R models have 4 valve heads.

so you're saying the 5 valve system is flawed? as in they have been doing this the wrong way by using 5 valves instead of 4? I find it puzzling that yamaha would use a flawed system for this long. :thumbsup::confused::thumbsup:

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so you're saying the 5 valve system is flawed? as in they have been doing this the wrong way by using 5 valves instead of 4? I find it puzzling that yamaha would use a flawed system for this long. :thumbsup::confused::thumbsup:
The 5 valve head has advantages in the lower speed range up to the bottom of what you could consider top end. This range is the area where engines operate much of the time. The trade off is in limitations as to the throughput at very high engine speeds, which limits the maximum power the engine can produce.

However, that is to talk about 450cc 4-stroke singles producing in excess of 60 horsepower (134 hp/liter). MX 450's currently are built to figures closer to 50-52 hp, which the 5 valve is quite capable of, so I wouldn't call it flawed. Almost everything in design work is a compromise of one kind or other, and it's just a matter of what you want to set aside to focus on your priorities.

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Seems odd that Yamaha pulled back on the FI when they had it last year over there. Back to the drawing board perhaps?

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Well that is a huge disappointment....I was hoping Yamaha would stick to the normal 3yr life cycle plan and come out with a spanking brand new 450 for 09. My wife may like this news because as of now I will still stay on my 06 until 2010....no need for less power and a new swingarm :thumbsup:

I hear ya, I was looking forward to getting an upgraded 09, now it looks like 10..

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Seems odd that Yamaha pulled back on the FI when they had it last year over there. Back to the drawing board perhaps?

that's what I was wondering when I saw that...

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I hear ya, I was looking forward to getting an upgraded 09, now it looks like 10..

wait till the dealer show in June(I think) and see what Yamaha releases. These are not for sure the '09 models, Yamaha has surprised us before.

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The 5 valve head has advantages in the lower speed range up to the bottom of what you could consider top end. This range is the area where engines operate much of the time. The trade off is in limitations as to the throughput at very high engine speeds, which limits the maximum power the engine can produce.

However, that is to talk about 450cc 4-stroke singles producing in excess of 60 horsepower (134 hp/liter). MX 450's currently are built to figures closer to 50-52 hp, which the 5 valve is quite capable of, so I wouldn't call it flawed. Almost everything in design work is a compromise of one kind or other, and it's just a matter of what you want to set aside to focus on your priorities.

60 horses? mmmmm... that sounds good. Are there any production bikes that get close to that figure, or are we talking about the bikes factory riders get to ride?

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