Hawk with Mikuni Help

[mac1029]

OK so trying to get this carb tuned and just would like a consensus of what i might need.
First off i have done the following; Air box mod w/K&N filter, upgraded exhaust,new iridium plug, and a mikuni with a 115 main and 25 slow, idle mix turned almost 2 turns due to mods, at 1 1/2 turns it didnt seem right.
I have followed similar set ups for the mods i have. i am also at 650ish elevation.
The issue i am getting is at idle when i blip the throttle just a bit it stalls, now if i roll on the throttle its fine?
is my idle jet too small? should i go to a 27.5 or 30?
is my main too small? go up to a 120?
All input is appreciated.

[JerryHawk250]

You might need a 27.5. Did you raise the needle? If you haven't, try raising it one notch first and see if that helps.

[mac1029]

Originally Posted by JerryHawk250

You might need a 27.5. Did you raise the needle? If you haven't, try raising it one notch first and see if that helps.

Thanks Jerry my needle is on the bottom notch, so it looks like i will go and order the 27.5 and 30 idle jets and try them out.
I just didnt know what i missed as i researched and try to set up the mikuni according to similar mods and found that the 115/25 was common.
Looks like each is its own beast...

[JerryHawk250]

Originally Posted by mac1029

Thanks Jerry my needle is on the bottom notch, so it looks like i will go and order the 27.5 and 30 idle jets and try them out.
I just didnt know what i missed as i researched and try to set up the mikuni according to similar mods and found that the 115/25 was common.
Looks like each is its own beast...

Yes then I would put a 27.5. The 25 is too lean. If you have to turn out more than 2 turns on the idle mixture still then try the 30. But the 27.5 should do it. As far as the main 115 should be good or may need to go to 117.5. Get the slow speed jet dialed in first then move on to tuning the main.

[Megadan]

Originally Posted by mac1029

Thanks Jerry my needle is on the bottom notch, so it looks like i will go and order the 27.5 and 30 idle jets and try them out.
I just didnt know what i missed as i researched and try to set up the mikuni according to similar mods and found that the 115/25 was common.
Looks like each is its own beast...

No two bikes are ever quite the same. The 25 pilot is a good starting point for a mostly stock bike. With an exhaust and intake, I found the 25 pilot to be a hair on the lean side, so I upped to a 27.5

This is why I always tell people to get a range of jet sizes for both main and pilot.

[mac1029]

Originally Posted by Megadan

No two bikes are ever quite the same. The 25 pilot is a good starting point for a mostly stock bike. With an exhaust and intake, I found the 25 pilot to be a hair on the lean side, so I upped to a 27.5

This is why I always tell people to get a range of jet sizes for both main and pilot.

Thanks guys,it is what i thought then , just wanted confirmation. I just placed a order for a range of pilot jets that goes up to 37.5, i already have a range of main jets, once again thanks

[Megadan]

Originally Posted by mac1029

Thanks guys,it is what i thought then , just wanted confirmation. I just placed a order for a range of pilot jets that goes up to 37.5, i already have a range of main jets, once again thanks

You shouldn't need anything larger than a 30.

[Weldangrind]

Originally Posted by mac1029

Thanks Jerry my needle is on the bottom notch...

I'm in agreement with the other guys on a 27.5 slow jet. That said, have you tried moving the clip up one notch? Does it get better or worse? It's a quick and free experiment.

[Megadan]

Originally Posted by Weldangrind

I'm in agreement with the other guys on a 27.5 slow jet. That said, have you tried moving the clip up one notch? Does it get better or worse? It's a quick and free experiment.

That's actually a great point that I overlooked. The needle in the 5th notch might be making the jet transition too rich, so when you quickly blip it the bike just bogs out.

[mac1029]

i will open it up and try moving it up 1 notch and see what i get.

[Megadan]

Just remember to make sure the bike is fully up to temp before making any calls on jetting changes. Go take it for a solid 5 to 10 minute ride and then see how it runs.