Freestyle Factory B Pipe 760/64x Tuning?

[Owen18]

Just bought a Factory B Pipe for my BOB Gen 1
I am running a limited 760/64x non-ported
Dual 44's or whatever comes with the GP760?
Was wondering if you guys knew where I could start for tuning, for the pipe, and what jets to run in my carbs?

 

[Crab]

Those are lean burn engines so I would probably go up to about 140 main

 

[SXR-FOREVER]

I am wondering the same thing, I picked up a 760 on the cheap and was going to use it as my spare.

This is what factory pipe says for the 760 pipe.. no idea if thats accurate or not.

Note: Make sure you check the stock jets
Main jet :130 on front (Mag) carb, 132.5 on rear (PTO)carb
Pilot Jet :115
High speed screw :½ turn out from closed on front(Mag) carb, 3/4 turns out on rear (PTO)carb
Low speed screw : 1-1/2 turns out from closed
Needle & Seat : (stock)
Spring : (stock)

 

[Matt_E]

Those are lean burn engines so I would probably go up to about 140 main

140 main....are you thinking of dual 38's? :clown:

am wondering the same thing, I picked up a 760 on the cheap and was going to use it as my spare.

This is what factory pipe says for the 760 pipe.. no idea if thats accurate or not.

Note: Make sure you check the stock jets
Main jet :130 on front (Mag) carb, 132.5 on rear (PTO)carb
Pilot Jet :115
High speed screw :½ turn out from closed on front(Mag) carb, 3/4 turns out on rear (PTO)carb
Low speed screw : 1-1/2 turns out from closed
Needle & Seat : (stock)
Spring : (stock)

Those specs sound like they are for a sitdown, with the staggered jetting. Which makes sense, because they 760 didn't really come with any factory Yamaha standup (RR760 edition excluded, and those were jetted equally).
Staggered jetting isn't needed in a standup.

I would look through the carb jetting data base and see what you find other people using.
The cylinder difference probably isn't as important as OEM vs retail 44 Mikunis.

 

[Owen18]

Actually probably matt.
So only thing I should change is main to 140?
Any chance I already have that, because I had the Pro-Tec wake up kit?

 

[orangefinger]

760 64X Dual 44's
145-135
120
N/S 1.5 95G
High 1.25
Low 1

For starters

 

[Owen18]

Where could i find those for my carbs?
and what about the B pipe screws?

 

[jd91t]

Where could i find those for my carbs?
and what about the B pipe screws?

Top and middle closed. Bottom open 1/2-3/4 turn. Then you can open the top 1/2 for a lil more low end if you like.

 

[1579]

Totally off topic, but how do you guys like the 760 powerband in a lighter hull?

Owen18, looks like you are doing well with that 760. Opinions?

Thanks

 

[Owen18]

My limited un-ported 760 has great power in an AM hull. Love it, but id recommend a ported 64x cylinder for greater bottom end power

 

[jamesgunter68]

What are your b pipe screws at?
The one on mine by where it says factory pipe is the only one open and is almost all the way out

 

[Owen18]

My middle is closed, and bottom about half, then top about half, I think....

 

[jamesgunter68]

the top is the one where it says factory pipe?

 

[Owen18]

yes, check factory pipe tuning specs, depending on your engine set-up