Jetting.

[leldolini69]

So....had the 1127 dyno'd today. Made 105 !!!!! Problem is over fuelling at top of rev range,lean at tick over but makes good power midrange. Running 6sigma carb kit:- 150 main,32.5 pilot,needle spaced as per instructions. Bst36 carbs,4-1 a16 stainless system,pipercross pods. everything else as is. 1st graph is full throttle run,2nd is throttle open whilst changing gear. Leans right off then riches up again after sticking next gear. Any help,advice,sarcasm etc great fully appreciated.

[dupersunc]

Isn't the point of running on the dyno to figure this out.  Find a yno operator that knows what they are doing. 

[MeanBean49]

Has someone just revved this up in a shed and badly drawn those graphs with a crayon?

As Dunc says, take it somewhere that has a clue and they will set it up for you.

Looks to me like its rich at the bottom end and lean at the top too. Not the other way round

Edited August 11, 2021 by MeanBean49

[dupersunc]

Looks rich at the top and bottom  end to me.  But yeah. what the fuck looks like the graphs were done on an Etch a Sketch.

[manden]

Pilots are kinda small. 145-150 main should be ok with unrestricted inlet and exhaust. Are the carbs cleaned? Plugs and ignition ok?

 

I agree to that the dyno operator should help out with trouble shooting. He had it under load and should with fairly ease be able to spot problems. It's atleast 20hp shy of its potential.