700N bogging on inverted climbouts...

[exiged]

Hi Guys,

My 700n is bogging bad when doing inverted punch outs,though its fine on regular climbouts.My pitch is +12-0-12 with a smooth ish line inbetween and ive leaned my YS91SR out as much as i want to as its coming down hot (dont have a temp gun).im governed at 1900 in idl2 (read somewhere thats around the peak rev range of the YS) so any ideas?

[tonystevens]

If your pitch is definately equal top and bottom, make sure your not running too lean then up your headspeed to 1950 maybe a little more. !900 is a tad too low for the YS. your not quite in the sweet spot

[exiged]

Ill give that a try chap.im sure i read it was 1800-1900rpm for the ys though,that may have been on a sunday morning with a belly full of jaegerbombs still though.

[tonystevens]

Had a similar thing with my ys, it kept dropping out of the power band at 1900, upped it to 1970 and it was spot-on.
What fuel you using?

[sacko]

You're not that far off with the headspeed as 1950rpm on the head is ideal. The powerband for the YS91 is approx 16000rpm and if youre running 8.2 gear ration, you end up with 1950.

Do you have a consistent smoke trail all the way up? Header tank or magnet fitted?

[exiged]

Thanks for the info guys.

yes its 8.2 gearing.consistent smoke all the way through and im using optifuel 20.

Ill up the head speed a little and se what happens.

[nightstalker]

I know you say that ur pitch is -12 but double check. I had a blonde moment once before and found I never set my pitch to -11 when in idle up. Always worth a double check mate