caseyjones955
Well-Known Member
Can exh packing effect jetting requirements? 4k stumble.
99 Vmax with 4-1 Kerker, stage 1 jet kit and drop in K&N. I have been doing some reading but a couple questions remain.
I'm seeing a stumble/miss from around 4000 to 5500 rpm, feels like starvation. I'm guessing when Vboost starts to open it resolves the starvation as it begins pulling from both carbs on each bank. It's more pronounced in higher gears, gentle acceleration masks the issue. I have to wonder how much top end power I might be leaving on the table along with the ridability issue.
The Kerker is loud, really loud. If the bike were jetted for a normal Kerker baffle but had the competition baffle (or just has the packing blown out) would the difference in back pressure be enough to lay on different jetting requirements?
I have read that electrical problems can cause symptoms like this. I duplicated the misfire yesterday and played with the choke and it didn't seem to make much difference. I'm at about 3500' and can double that on a day ride. The stage 1 kit was installed with the 170 mains. Not really sure where to go from here, it would seem there is plenty of main jet installed already. What other factors or adjustments might I try before tearing into it?
Thanks.
99 Vmax with 4-1 Kerker, stage 1 jet kit and drop in K&N. I have been doing some reading but a couple questions remain.
I'm seeing a stumble/miss from around 4000 to 5500 rpm, feels like starvation. I'm guessing when Vboost starts to open it resolves the starvation as it begins pulling from both carbs on each bank. It's more pronounced in higher gears, gentle acceleration masks the issue. I have to wonder how much top end power I might be leaving on the table along with the ridability issue.
The Kerker is loud, really loud. If the bike were jetted for a normal Kerker baffle but had the competition baffle (or just has the packing blown out) would the difference in back pressure be enough to lay on different jetting requirements?
I have read that electrical problems can cause symptoms like this. I duplicated the misfire yesterday and played with the choke and it didn't seem to make much difference. I'm at about 3500' and can double that on a day ride. The stage 1 kit was installed with the 170 mains. Not really sure where to go from here, it would seem there is plenty of main jet installed already. What other factors or adjustments might I try before tearing into it?
Thanks.