Thoughts on the readout?

[Magic1971]

Passed mot and went on the rolling road dyno thing, readout shows at low end its running a bit rich shows its at about 10 to 1 air and fuel then creeps up midrange and topend 13 to 1 thought I'd see what anyone thought on this !!guy said maybe drop pilot jet back down think I put 40 in from 37.5 should I do this also should I worry about mid and top end its not far off I think main jet is now 145 and needle clip position 3 out of 5 factory pro jet kit. K&n filter air box cut open and viper race cans fitted . Did say power transfer all appears quite smooth thanks all

[Dookbob]

Sounds like the needle is in the correct grove if the midrange is ok. I would be inclined to do as you say and reduce the pilot jet, then you can fine tune the tick over on the throttle stop and idle mixture screws.

[Magic1971]

Cheers, its all a bit of a learning curve for me, guy did say could possibly drop main jet but mid range and top end running at only very slightly rich am wondering do I really want to mess with that and risk over compensating? will have a go at pilot jet then as you say dook (quick chuckle my predictive text wanted to change dook to fool :-) ) maybe just tweak the idle and mixture screws, only thing is not paying another £30 for them to tell me what it's at will just have to judge by it feeling ok running, not sure if this is a running rich clue or not but on start up really needs hardly any choke even in today's cold weather, then have to take choke off pretty quick also once I've ran it for a minute or so will not start if I give it any throttle only starts if I just push button is that normal or an indication it's a bit rich ? Cheers

[Dookbob]

If its starting without choke in the current temperatures it has got to be rich, but you have already found that out from the dyno readout. So I would do as suggested and reduce the pilot jets. Another thing I would check before doing anything is make sure that the choke levers are closing completely with a bit of free play on the choke lever.
My predictive text on my IPad gives me DOORKNOB instead of Dookbob.

[Magic1971]

Good point will have a look, also been looking at the jets I've change stock pilot is 37.5 I've put 40 in also stock main is132.5 I've gone to 145 quite a jump I suppose but not drastic on the readout and I did select the jet to go with k&n and exhaust but looking at it closer its more like to 12:1 than 13:1 at mid and top I do have some 140 mains that came with kit also, rather than drop needle a position is it possible to take out the metal washer that sits over needle this would drop it a bit finer, the readout shows its on the 10:1 mark up to about 50mph then rises to 12:1 mark will check the choke out though would love to get it close to good

[Dookbob]

Don't discard any washers, if Mikuni didn,t need the washers, they wouldn't,t have put them in there.

[Mr Gremlin]

the washers are there to give you 1/2 clip increments, but personally, i would lower the fuel height first, it would probably sort out all of your richness, right across the range :)

[Dookbob]

I assume that would require raising the float hieghts in order to lower the float levels.I didn,t realise that the needle washers were there to give a smaller increment adjustment, thanks for that. Have you got that Magic?

[Magic1971]

Yes cheers the float heights did concern me when I put jet kit in but when I measured them they were at 14mm that's what it said they should be changing the heights worries me as not tackled that before and looks like I could cock that up

[Mr Gremlin]

not really,if you measure them first, you can always put them back.