81 Xs400 special 2 Bs34

[Prisondawg]

Hello im looking to get new jets for my 81 xs400 special 2 Bs34 carbs. I need to order new jets for it. The mains in there are 142.5 which are too big. I believe stock is 135.

I also want to order 42.5 pilots since the current ones in there are marred up and stripped.

I was going to try and order them from niche cycles but I'm not sure the part number , I was wondering if someone could help me with that.


Also what is the best way to removed a stripped pilot jet from a BS34?

And the carb guide says the best case for fuel mix screw is 3 turns out. Is that true for Xs400's as well?


Thanks for any help

 

[Jim]

Not sure if you know or not, but we have a sister site for the 400's..... XS400.com You might get more accurate answers there. Good luck.

 

[Prisondawg]

Not sure if you know or not, but we have a sister site for the 400's..... XS400.com You might get more accurate answers there. Good luck.

I am registered there but from what I can tell from nosing around, With few exceptions, the 650 community is more savvy. and since the Bs34 is shared from the 650 I figured this would be a good place to ask . What ever I find out here I'll repost the answers over there to help that community

 

[Mailman]

Not sure if you know or not, but we have a sister site for the 400's..... XS400.com You might get more accurate answers there. Good luck.

Well....I’ll be! I’ve been here for years and never realized that. How come they got more t shirts? And cool ones too!

 

[650Skull]

A couple of tips in here that can be applied to your problem
http://www.xs650.com/threads/stripped-mixture-screw-bs34-removal-and-replacement.10044/

Use Partzilla for part no's, it also shows the jet sizes. Would assume they are what comes from the factory.......
https://www.partzilla.com/catalog/yamaha/motorcycle/1981/xs400sh/carburetor

 

[xjwmx]

That's a good idea. Whether the BS34s for the 400 use the same model of jets as the 650 is a question itself.

 

[Jim]

Well....I’ll be! I’ve been here for years and never realized that. How come they got more t shirts? And cool ones too!

Yeah... Travis is a prolific guy. He's also got CB750.com.

 

[Mailman]

Yeah... Travis is a prolific guy. He's also got CB750.com.

Well, what else don’t I know?

 

[Jim]

Well, what else don’t I know?

I dunno Bob... what else don't you know?

 

[Jim]

I don't think Travis gets near enough credit for the hard work he does for the vintage Japanese bike community.

 

[Mailman]

I don't think Travis gets near enough credit for the hard work he does for the vintage Japanese bike community.

I’m beginning to realize that! That’s a lot of work!

 

[5twins]

Although the XS400 Bs34s differ a bit externally (linkage, mount spacing, fuel line connections), internally they are pretty much the same as the 650 version. They use the same type of jets. The pilots are the BS30/96 type .....

The mains are Mikuni large round mains, the N100/604 type .....

 

[Prisondawg]

Although the XS400 Bs34s differ a bit externally (linkage, mount spacing, fuel line connections), internally they are pretty much the same as the 650 version. They use the same type of jets. The pilots are the BS30/96 type .....

The mains are Mikuni large round mains, the N100/604 type .....

This is the information I needed. Xs400.com need a 5twins. Thank you.

 

[5twins]

Seeing that the jetting is very near the same as the 650's, and the pilot jet is the same, I think the mix screw setting will be the same as well - 3 to 3.5 turns out.