Re: A35 Polini + 19mm PHBG Race Questions

Graham Motzing /
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i think both you guys know what you are trying to say but the way you are saying it is somewhat confusing

the w7 needle has the transition point lower than the w9 so it adds needle jet fuel mix at a larger throttle opening.

if you go back and look at the chart of what tuning parts are affecting what range of throttle opening- the 'straight shaft' portion of the needle blocks almost all of the fuel flow through the needle jet orifice until the taper kicks in. Up until the throttle is open on that taper, all the fuel flow is coming through the pilot jet, via the atomiser holes and being controlled by the air bleed screw.

once the slide is up far enough to hit the taper portion, it opens up that needle jet orifice and fuel begins to flow.

if you are getting a dead spot before it hits the transition point- like eric is talking about- you can go from the W7 to the W9 and it will add more fuel. or vise versa if it is kicking in too soon.

it all depends on how progressive your setup is and the airflow for a relative carb size. Get your pilot jet adjustment as good as you can for the 0-1/3 throttle condition, then adjust your needle jet to start kicking in. If you have a smaller carb you'll be getting a stronger pressure signal whereas a larger carb wont get as strong of a pressure signal (which pulls fuel from the pilot jet) and might need more flow being added mechanically from the needle.

Lots of bikes that other people have tuned that i ride have this screwed up, Eric is dead on when you are riding with a group and trying to modulate throttle, this will drive you crazy if you dont get it nailed down.

This single post is part of a larger thread. Start from the top or view this post in context.
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  A35 Polini + 19mm PHBG Race QuestionsTopic by: B DM B DM 04/20/19 06:24PM
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  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/20/19 06:52PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: Daniel '' Daniel '' 04/20/19 07:11PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: * * * * 04/20/19 08:17PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/20/19 08:21PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: * * * * 04/20/19 09:08PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/20/19 09:18PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: * * * * 04/20/19 09:37PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/20/19 09:45PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: EH FCC of the QCB EH FCC of the QCB 04/21/19 04:29PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: * * * * 04/21/19 10:02PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/20/19 09:59PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: * * * * 04/20/19 11:00PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/20/19 11:32PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: * * * * 04/21/19 11:45AM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: Graham Motzing Graham Motzing 04/22/19 11:51AM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: * * * * 04/22/19 03:54PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/22/19 09:11PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: Mike Boyd Mike Boyd 04/22/19 09:18PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: P D P D 04/22/19 09:40PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/22/19 09:52PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: P D P D 04/22/19 10:10PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/22/19 10:17PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/22/19 09:50PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: Mike Boyd Mike Boyd 04/22/19 11:35PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/23/19 01:05PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: Buttcheeks BUZZARD Buttcheeks BUZZARD 04/23/19 02:05PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: Graham Motzing Graham Motzing 04/23/19 11:38AM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/23/19 01:04PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: Graham Motzing Graham Motzing 04/23/19 03:27PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/23/19 01:19PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: Buttcheeks BUZZARD Buttcheeks BUZZARD 04/23/19 02:06PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: Mike Boyd Mike Boyd 04/23/19 02:08PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/23/19 02:09PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: Mike Boyd Mike Boyd 04/23/19 03:26PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: B DM B DM 04/23/19 04:05PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: Daniel '' Daniel '' 04/23/19 03:13PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: * * * * 04/24/19 01:55PM
  Re: A35 Polini + 19mm PHBG Race QuestionsRe: Bill Mazzacane Bill Mazzacane 04/25/19 03:20AM

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