yamaha Japan yzf 450 2020 - NEW HEAD

DB97 wrote:

Shock looks different too?

DB97 wrote:

Shock looks different too?

#434 wrote:

Both designs have been around for some time. One has a tilted resovoir to keep it away from the heat of header pipe. The internals should...

Both designs have been around for some time. One has a tilted resovoir to keep it away from the heat of header pipe. The internals should be the same.

Motofinne wrote:

No hydro clutch That is probably the only thing i miss on my 2019 450.

That alu tank wont probably come on the stock 2020 bikes?

cody41 wrote:

They need to scrap the air box set up and tilted back head/cylinder already.

ML512 wrote:

Yamaha has regularly done a mid-generation change, this would be year 3 of 4 or year 3 of 5 for this model’s generation. The shock looks...

Yamaha has regularly done a mid-generation change, this would be year 3 of 4 or year 3 of 5 for this model’s generation. The shock looks normal on that bike, the second bike pictured had the leaned back reservoir that KYB produced for the Japan team a few years ago. I think the Rinaldi team used it once season too.

Although, both bikes feature a production sized adjuster that is the high/low comp and low speed rebound. Which the Yamaha has yet to come with on production.

ML512 wrote:

Yamaha has regularly done a mid-generation change, this would be year 3 of 4 or year 3 of 5 for this model’s generation. The shock looks...

Yamaha has regularly done a mid-generation change, this would be year 3 of 4 or year 3 of 5 for this model’s generation. The shock looks normal on that bike, the second bike pictured had the leaned back reservoir that KYB produced for the Japan team a few years ago. I think the Rinaldi team used it once season too.

Although, both bikes feature a production sized adjuster that is the high/low comp and low speed rebound. Which the Yamaha has yet to come with on production.

mattyhamz2 wrote:

Michael, a bit off topic, but any word on the RMZ450 coming with E-Start for 2020?

ML512 wrote:

Yamaha has regularly done a mid-generation change, this would be year 3 of 4 or year 3 of 5 for this model’s generation. The shock looks...

Yamaha has regularly done a mid-generation change, this would be year 3 of 4 or year 3 of 5 for this model’s generation. The shock looks normal on that bike, the second bike pictured had the leaned back reservoir that KYB produced for the Japan team a few years ago. I think the Rinaldi team used it once season too.

Although, both bikes feature a production sized adjuster that is the high/low comp and low speed rebound. Which the Yamaha has yet to come with on production.

mattyhamz2 wrote:

Michael, a bit off topic, but any word on the RMZ450 coming with E-Start for 2020?

motox331 wrote:

No Estart but I think they are coming out with a revolutionary new kick start lever............polished

ML512 wrote:

Yamaha has regularly done a mid-generation change, this would be year 3 of 4 or year 3 of 5 for this model’s generation. The shock looks...

Yamaha has regularly done a mid-generation change, this would be year 3 of 4 or year 3 of 5 for this model’s generation. The shock looks normal on that bike, the second bike pictured had the leaned back reservoir that KYB produced for the Japan team a few years ago. I think the Rinaldi team used it once season too.

Although, both bikes feature a production sized adjuster that is the high/low comp and low speed rebound. Which the Yamaha has yet to come with on production.

mattyhamz2 wrote:

Michael, a bit off topic, but any word on the RMZ450 coming with E-Start for 2020?

#434 wrote:

Here's the Kawi head for comparison: [img]https://p.vitalmx.com/photos/forums/2019/04/17/339565/s1200_kx.jpg[/img]

Here's the Kawi head for comparison:

#434 wrote:

Here's the Kawi head for comparison: [img]https://p.vitalmx.com/photos/forums/2019/04/17/339565/s1200_kx.jpg[/img]

Here's the Kawi head for comparison:

usp4u wrote:

So how is lash adjusted ?

ML512 wrote:

Yamaha has regularly done a mid-generation change, this would be year 3 of 4 or year 3 of 5 for this model’s generation. The shock looks...

Yamaha has regularly done a mid-generation change, this would be year 3 of 4 or year 3 of 5 for this model’s generation. The shock looks normal on that bike, the second bike pictured had the leaned back reservoir that KYB produced for the Japan team a few years ago. I think the Rinaldi team used it once season too.

Although, both bikes feature a production sized adjuster that is the high/low comp and low speed rebound. Which the Yamaha has yet to come with on production.

mattyhamz2 wrote:

Michael, a bit off topic, but any word on the RMZ450 coming with E-Start for 2020?

ML512 wrote:

When I asked like 16 months ago the answer I got seemed more like '21. But maybe they've sped it up if it's just a case...

When I asked like 16 months ago the answer I got seemed more like '21. But maybe they've sped it up if it's just a case redesign.

cody41 wrote:

They need to scrap the air box set up and tilted back head/cylinder already.

-espionage- wrote:

Can't tell if that's sarcasm or not.

#434 wrote:

Shims between the valve and the finger follower.

cody41 wrote:

They need to scrap the air box set up and tilted back head/cylinder already.

-espionage- wrote:

Can't tell if that's sarcasm or not.

cwtoyota wrote:

I was wondering that too.
Cody, if it's a serious comment, care to explain why?

#434 wrote:

Shims between the valve and the finger follower.

usp4u wrote:

Okay, so they haven't really removed the number of parts? The rocker replaces the old bucket/tappet. Yet there is now a follower that is pivoting on...

Okay, so they haven't really removed the number of parts?

The rocker replaces the old bucket/tappet. Yet there is now a follower that is pivoting on a shaft that was previously unnecessary.

Now, I can see that eliminating the bucket saves some reciprocating valvetrain weight, and that is always a good thing, BUT.........that is almost ALWAYS done to:

-improve valvetrain stability (not really an issue with the previous design)
-allow lower spring pressures
-continue using high spring pressures allowing for greater RPM ceiling (how much higher does a 450 need to rev?)

What I'm seeing is:
-No reduction in number of parts
-FOUR brand new wear surfaces that didn't exist before (the follower axles)
-Increase in frictional losses
-Narrower loading surface (I'll bet the cam lobes and the follower are narrower than traditional lobe/bucket, more aggressive cam profiles and faster ramps with less loading surface)
-Static wear patterns (cam and follower will wear together likely demanding all parts be replaced during a cam change


I'm sure all of these are unfounded. But the engine builder in me fails to see the "breakthrough" in this exercise.

#434 wrote:

Shims between the valve and the finger follower.

usp4u wrote:

Okay, so they haven't really removed the number of parts? The rocker replaces the old bucket/tappet. Yet there is now a follower that is pivoting on...

Okay, so they haven't really removed the number of parts?

The rocker replaces the old bucket/tappet. Yet there is now a follower that is pivoting on a shaft that was previously unnecessary.

Now, I can see that eliminating the bucket saves some reciprocating valvetrain weight, and that is always a good thing, BUT.........that is almost ALWAYS done to:

-improve valvetrain stability (not really an issue with the previous design)
-allow lower spring pressures
-continue using high spring pressures allowing for greater RPM ceiling (how much higher does a 450 need to rev?)

What I'm seeing is:
-No reduction in number of parts
-FOUR brand new wear surfaces that didn't exist before (the follower axles)
-Increase in frictional losses
-Narrower loading surface (I'll bet the cam lobes and the follower are narrower than traditional lobe/bucket, more aggressive cam profiles and faster ramps with less loading surface)
-Static wear patterns (cam and follower will wear together likely demanding all parts be replaced during a cam change


I'm sure all of these are unfounded. But the engine builder in me fails to see the "breakthrough" in this exercise.