787 just won’t rev

[Flyer1275]

I’ve gotten ahold of a 1997 gtx 787
Compression 130 per cylinder
Went thru the carbs put wsm kits in them set pop off at 30
Low end mix at 1.5 turns
High end at zero
Unit starts, and runs when you open the throttle engine turns up to 7000 pulls hard
For a few seconds then falls on its nose and won’t turn higher then 4000
I have slowly open the throttle past 1/4 it falls on its nose and occasionally will stall I’ve tried both high and low mixture screw adjustments just can’t seem to find the spot Any ideas

 

[mikidymac]

WSM carb kits are one your issues.
Only use Genuine Mikuni carb parts.

 

[Flyer1275]

WSM carb kits are one your issues.
Only use Genuine Mikuni carb parts.

I never had issues with Edmonton kits in yamaha I’ve got Mukuni kits I’ll put them in tomorrow Let you know what the result

30 sound right on pop off?

 

[KyleW2]

97 GTX pop off is 23-43 so 30 is in spec.

 

[mikidymac]

Make sure you don’t use the springs in the kits either.

 

[etemplet]

Pop-Off with the correct spring and Genuine Mikuni Carb parts should be around 36psi. Good Luck !