Carburetor differences! Understanding the changes...

[Shuriken]

My picture shows 2 carburetors side by side. The one on the left is from my 2002. The one on the right is from an unknown year.

Notice the R5 ID on the casting as well as the different internal tunnel length difference.

What was Yamaha doing here and is it ok to interchange?

 

[CaptainKyle]

I sent a message

 

[Graham]

The one on the left, is that a California model carb?

 

[Shuriken]

The one on the left, is that a California model carb?

I hope not!

As far as I know, my 02 is not the C model.

 

[Onetwomany]

For what’s it worth, I have a C model, and mine looks like the one on the left

 

[Shuriken]

For what’s it worth, I have a C model, and mine looks like the one on the left

Interesting. Thanks for posting. I have read that the C models had an extra port or something similar for extra emissions control. Someone can clarify. Can you take a pic of your carbs from the left leg side?

I think it is probably a design change based on year rather than C model though. I think the newer carbs probably got enhanced. Why else would Yamaha change their tooling?

I would like to specifically find out why the newer ones have that different casting tunnel.

I just mixed the one on the right in with 3 of the newer ones. I don't know how I would be able to determine its effect on performance though.

 

[apsolus]

Interesting. Thanks for posting. I have read that the C models had an extra port or something similar for extra emissions control. Someone can clarify. Can you take a pic of your carbs from the left leg side?

I think it is probably a design change based on year rather than C model though. I think the newer carbs probably got enhanced. Why else would Yamaha change their tooling?

I would like to specifically find out why the newer ones have that different casting tunnel.

I just mixed the one on the right in with 3 of the newer ones. I don't know how I would be able to determine its effect on performance though.

bro im a mechanic by trade, OEM's never need an excuse to retool! lol ive stopped trying to make sense of it all haha