sandmanmike1
New member
I have a 94 VMAX 600 ST that had a new top end done last year. When I did the top end I replaced the stock reeds with boyesen reeds because the stock ones were worn. It was running a little rich at idle after reed change. Since then I installed single GYT pipe from a 96 and carbs from a 96 XT also. Well it is still running rich. Stock carbs were 36mm with 157.5 jets. The 96 carbs are 38mm with 152.5 mains. Where should I start to lean it out a little. I ordered some 150 mains. Should I go even smaller and what should I do with pilot jet and or air screw or needle position. Elevation is around 800 feet. Also is a little hard to start. Flooding out I beleive. Thanks in advance. Mike
well you have to work in steps, first you have to address the low speed circuit, what pilot jet did you run before?? what is in the new carbs? the pilot jet controls the fuel flow at idle and low throttle settings, so hard starting can be from too big of a pilot, or even too small, also the float level needs to be correct, a high float level will cause a rich condition in the carb.
after the low speed circuit is done, you move onto the needles, this is your mid throttle, what clip are the old ones at? new ones? the needles and nozzles are most likley differnt and flow differnt amounts but this will get you able to tune from there.
Lastly will be your main jet, this controls your wide open setting, the 38 will require a slightly bigger main as its a larger carb, more airflow will need more fuel.
after the low speed circuit is done, you move onto the needles, this is your mid throttle, what clip are the old ones at? new ones? the needles and nozzles are most likley differnt and flow differnt amounts but this will get you able to tune from there.
Lastly will be your main jet, this controls your wide open setting, the 38 will require a slightly bigger main as its a larger carb, more airflow will need more fuel.
sandmanmike1
New member
I think the only difference between the 94 and 96 motors is the clutching carbs and pipe. So motor is basically a stock 96 with boyesen reeds. 94 and 95 has 36mm carbs and 96 had 38mm. 36mm came with 156.5 stock main jet the 38mm 96 carbs came 152.5 mains. Pilot jet has not been changed. My sled is up north 250 miles away. My dad is going to check the air screw today I think. I am going to check things out between X-Mas and New year. Only have 3 weeks until big ride in Au Train. We may hit munising one day also.
The 96 xt motor uses a different cylinder than the 95's. Its the same as on the 97up 600 twin. Boost port in the cylinder, and different exhaust ports too. Might be some other differences in the port heights and such, but I wasn't looking that close when I swapped them around.