Hate to be a dummy, but what does "BSR" stand for? I can find referrences to "HSR" on Mikuni's site, but can't find a thing about BSR except for a list of the machines that use them.

Even searched Google....can't find a thing.

 

BSR is the variable venturi (vacuum operated) 4-stroke carb. As you move the throttle, the throttle plaste moves, and the differential in vacuum acts on a diaphragm. That diaphragm then moves the slide. Someone can correct me if I'm wrong. I'm familiar with the TMX line of flatslide Mikuni's (Hot Seat sells them), that's where the slide/throttle valve is all one unit. When you squeeze the throttle, the one slide moves. Hope this clears a little fog.

 

Thanks ModQuad....

So, are you saying the BSR uses a flat slide also? Is this design (the variable venturi/vaccuum operated) probably a main factor for the snappy starts on a Predator? Please excuse the dumb questions, I'm seriously looking at a Predator, but want to try and understand a little about the design before I just dive in.

I wish I could see a diagram of this carb. I think a Raptor uses two smaller Mikuni BSRs, don't they? Maybe I can find some kind of a diagram on a Raptor or Yamaha site or something.

thanks again for the info!

 

I'm not a Genie in a bottle, but here is your wish come true. LOL Carb

 

OMGosh! That is EXACTLY what I was looking for!

Thanks NCScrambler...er, uh...Genie!

 

LOL. Sorry I can only grant one wish today. Your welcome

 

Well, shoot! My next wish was that a new Predator would magically appear in my garage tomorrow morning. But, this will do for now!

It's basically a CV carb? Man-o-man...a whole nother world from the carb on my Warrior I just sold. And I was just starting to get it on how that thing worked. From simple to complicated. Yikes!

 

You can have the Predator in your garage, already have one. I'll take Christina Agulera (originally sang "genie in a bottle") [img]i/expressions/face-icon-small-happy.gif[/img]

 

Yeh, ok I am sending her on her way and she is wearing a Hooter's uniform!!!! LOL

 

Hey you BSR experts seem to have the answer so maybe you can help this old codger with a similar problem. I have a 199 7Suzuki king quad LT-4WD and the machine just suddenly began acting as if it were flooding and when I held the throttle wide open it cleaned out but the problem persisted and got worse, On inspecting the air filter I found it disintegrated, it sat for long, time and so replaced it and thought the problem was solved only to find that it has just gotten worse. Carb has been completely cleaned but it will not lift the CV slide above about 1/3 throttle at which point it acts like it is starving which I am sure it is. Everything is working freely but the slide will NOT lift enough to take full throttle. The diaphragm is nice and flexible. Fuel pump is delivering fuel. What are your thoughts. I can't find a BSR on mikuni site but believe it is a BSR, it is a CV for sure. Email me at jyrasco1936@gmail if you have any ideas on h cure it!. Thanks. Jay Rasco