Rich or Lean

[ebenviljoen]

I bought a flo commander and fitted it. Works great. But before, I fitted a pipercross filter and dynojet kit. Bike ran fine but low revs got a slight cough through the carbs now and again. So when I fitted the F/C i turned the A/F screw in and out 2 and half turns, to cure the cough at low revs. But now it's running a little hot and goes below set idle revs. I thought that before hand my A/F screw was out 2 turns, but I am not sure now. The bike starts easy enough and runs fine with mid to high revs. When in town, it runs a little hot. Ive set the idle speed at 1400. So ill blib the throttle, it'll idle at 1400 rpm then drops to 1000rpm. Is this rich or lean? im confused now! lol, running hot might be in my head though as it only goes to the mid point of the heat guage, so probably normal. just the idleing that confuses me. I dont have an angled driver to adjust the screws and need to take everything off to adjust the screws. I think it's to rich now but want to see what others might think.

Im gunna get it on the dyno soon to fine tune with the Flo commander but want to sort the low revs out first

[bazza696]

can't you just turn the Idle up!

[Tweety]

I bought a flo commander and fitted it. Works great. But before, I fitted a pipercross filter and dynojet kit. Bike ran fine but low revs got a slight cough through the carbs now and again. So when I fitted the F/C i turned the A/F screw in and out 2 and half turns, to cure the cough at low revs. But now it's running a little hot and goes below set idle revs. I thought that before hand my A/F screw was out 2 turns, but I am not sure now. The bike starts easy enough and runs fine with mid to high revs. When in town, it runs a little hot. Ive set the idle speed at 1400. So ill blib the throttle, it'll idle at 1400 rpm then drops to 1000rpm. Is this rich or lean? im confused now! lol, running hot might be in my head though as it only goes to the mid point of the heat guage, so probably normal. just the idleing that confuses me. I dont have an angled driver to adjust the screws and need to take everything off to adjust the screws. I think it's to rich now but want to see what others might think.

Im gunna get it on the dyno soon to fine tune with the Flo commander but want to sort the low revs out first

Why not use the old tried and true test of rich/lean? Choke or enricher circuit... If it helps, you are lean, if not, you are rich... Simple...

[ebenviljoen]

Why not use the old tried and true test of rich/lean? Choke or enricher circuit... If it helps, you are lean, if not, you are rich... Simple...[/quote]

deffo rich. I need one of them little adjuster tools. can anyone recommend one?

[VTRDark]

Woh hold on a minute. First of all you need to understand that the flow commander only works on the mains as it connects to the main air jet/bleed on top of the carbs. IIRC turning all the way in one direction or the other is the equivalent of going up or down a main jet size. Ideally your carbs should tuned perfectly with the flow commander set to a neutral position. So you can use this as a tool to determine whether your rich or lean on the mains. Adjuts the size of the main accordingly and then set the flow commander back to neutral. It also has the other benefit of smoothing out the turbulent air within the airbox which helps with the emulsification of fuel and air. Once your carbs are set up properly with the flow commander back to neutral, you can then fine tune with it slightly either way.

So with that said the following

Bike ran fine but low revs got a slight cough through the carbs now and again. So when I fitted the F/C i turned the A/F screw in and out 2 and half turns, to cure the cough at low revs.

This Is not going to have much if any affect on pilot circuit/low revs.

Both the excess heat and coughing and/or stuttering usually suggest Lean. And as your rev the the bike the needle will not rev cleanly and come back to the set idle, so you have a problem with the fuel mixture A/F screw setting. If you do as Tweety suggested and pull the choke out slightly, very slightly (a few mm) then this will richen things up a tad as the choke enrichens the mix. You will most likely notice that the cough will disappear at low revs which will prove you to be lean.

Really you need to get the mains sorted first, then move onto the needle height and then worry about the pilot circuit. if the mains are not correct then this will have an effect on the appropriate needle height and if the needle height is not correct then this will have an effect on the pilot. The fuel screw should be set as good as you can get it all the way through all circuits. It will have a small effect on the mains, it will have even more effect on the needles and mostly effects the pilot and idle circuit.

I suggest you have a read through the carb tuning guide in my signature.

As for a screwdriver for adjusting the A/F screws it helps but is still a little fiddly, especially the rear. And what really takes the time to learn is listening to the engine note for the idle drop procedure for getting the right setting. It's a little easier to use the blip test as you adjust the screw either richer or leaner.

I use one of these.
http://www.motionpro.com/motorcycle/partno/08-0229/

There are alternatives like the following.
http://www.motionpro.com/motorcycle/partno/08-0119/
Have a look on ebay you will find some in there.

(:-})

[ebenviljoen]

I have sorted it. I realise the Flo commander dont regulate the low revs. I got the bike running as good as i could with the dynojet kit starting at high rpm, then mid range with needle position . The bike then coughed at very low rpm. But when i fitted the flo commander to fine tune but then out with the af screw to sort cough out. I asked the question to save me from taking the carbs off twice. It was rich, screws are at 2 1/4 turn each and the bike runs perfect now. I fine tuned the fc now too, from the base setting quaeter turn leaner. Guanna get it on the dyno now, see how ive done, the wheel lifted on my last test run!! think i was vague on my initial question

[mik_str]

How do you like the Pipercross? Any difference in power? Required jetting changes?

[lloydie]

How do you like the Pipercross? Any difference in power? Required jetting changes?

+1 as I have one now and after a review

[ebenviljoen]

Its good but you deffo need to.re-jet. The set up that worked for me is pipercross with dynojet kit. My main jet is #190 and needle on clip nr 4. And the 3rd auxilry hole drilled. Evey one told me not to drill it but in my case 4th clip is a little lean but 5 rich. So i drilrilled the hols and worked a treat for me. My pilots are standard #48 but ive read that early years was #45? Double check on that tho guys. The filter works a treat now, but standard carb with pipercross it pulls like a bag of dhite! Good gain in power with filter and rejet and the filter makes a good sound too. Ive got scorpion cans with no baffles and with this setup my front wheel lifts and without me trying. Ill post a dyno sheet soon with results

[Tweety]

Its good but you deffo need to.re-jet. The set up that worked for me is pipercross with dynojet kit. My main jet is #190 and needle on clip nr 4. And the 3rd auxilry hole drilled. Evey one told me not to drill it but in my case 4th clip is a little lean but 5 rich. So i drilrilled the hols and worked a treat for me. My pilots are standard #48 but ive read that early years was #45? Double check on that tho guys. The filter works a treat now, but standard carb with pipercross it pulls like a bag of dhite! Good gain in power with filter and rejet and the filter makes a good sound too. Ive got scorpion cans with no baffles and with this setup my front wheel lifts and without me trying. Ill post a dyno sheet soon with results

Drilling holes in sliders have absolutely zero effect on lean/rich condition... It affects the speed of the slide, not the mixture... So, something is not adding up here...

[Hairy biker]

I too run a piper cross and empty scorpions, I don't don't know if its got the dyno jet kit though as these were fitted when i bought the bike, it didn't run very well to start with, went like stink but but idle was cr@p/cutting out and just generally lumpy even by v twin standards,I've just about got it set up now although I think it may be just a smidge lean as it occasionally sneezes when you blip the throttle after a long blast, apart from that it goes well enough

[ebenviljoen]

Its good but you deffo need to.re-jet. The set up that worked for me is pipercross with dynojet kit. My main jet is #190 and needle on clip nr 4. And the 3rd auxilry hole drilled. Evey one told me not to drill it but in my case 4th clip is a little lean but 5 rich. So i drilrilled the hols and worked a treat for me. My pilots are standard #48 but ive read that early years was #45? Double check on that tho guys. The filter works a treat now, but standard carb with pipercross it pulls like a bag of dhite! Good gain in power with filter and rejet and the filter makes a good sound too. Ive got scorpion cans with no baffles and with this setup my front wheel lifts and without me trying. Ill post a dyno sheet soon with results

Drilling holes in sliders have absolutely zero effect on lean/rich condition... It affects the speed of the slide, not the mixture... So, something is not adding up here...

Whatever the reason then, the third auxilery hole works on mine.

[ebenviljoen]

I too run a piper cross and empty scorpions, I don't don't know if its got the dyno jet kit though as these were fitted when i bought the bike, it didn't run very well to start with, went like stink but but idle was cr@p/cutting out and just generally lumpy even by v twin standards,I've just about got it set up now although I think it may be just a smidge lean as it occasionally sneezes when you blip the throttle after a long blast, apart from that it goes well enough

I think it will be re-jetted somehow mate coz i stuck the pipercross on with standard carbs and empty scorpion cans and it ran like a bag of dung, but then every engine is different ive been told loads. If it was me i would have taken the carbs apart and look if a jet kit was fitted, i like to know what goes on in my engine! Lol

[Hairy biker]

I too run a piper cross and empty scorpions, I don't don't know if its got the dyno jet kit though as these were fitted when i bought the bike, it didn't run very well to start with, went like stink but but idle was cr@p/cutting out and just generally lumpy even by v twin standards,I've just about got it set up now although I think it may be just a smidge lean as it occasionally sneezes when you blip the throttle after a long blast, apart from that it goes well enough

I think it will be re-jetted somehow mate coz i stuck the pipercross on with standard carbs and empty scorpion cans and it ran like a bag of dung, but then every engine is different ive been told loads. If it was me i would have taken the carbs apart and look if a jet kit was fitted, i like to know what goes on in my engine! Lol

I've had the carbs apart a few times but probably rather foolishly
Never paid attention to the jet sizes I was just trying to get it to run properly, but from what you say it most likely has been re jetted to suit 'cos it can move.

[ebenviljoen]

Its good but you deffo need to.re-jet. The set up that worked for me is pipercross with dynojet kit. My main jet is #190 and needle on clip nr 4. And the 3rd auxilry hole drilled. Evey one told me not to drill it but in my case 4th clip is a little lean but 5 rich. So i drilrilled the hols and worked a treat for me. My pilots are standard #48 but ive read that early years was #45? Double check on that tho guys. The filter works a treat now, but standard carb with pipercross it pulls like a bag of dhite! Good gain in power with filter and rejet and the filter makes a good sound too. Ive got scorpion cans with no baffles and with this setup my front wheel lifts and without me trying. Ill post a dyno sheet soon with results

Drilling holes in sliders have absolutely zero effect on lean/rich condition... It affects the speed of the slide, not the mixture... So, something is not adding up here...

Behind a pc so can explain my thinking a bit better now. When I first installed the kit Carl explained to me that the 3rd hole makes it lift too quickly and upsets everything by richening things up a bit. The dynojet stage 1 kit is not aimed at aftermarket filters but standard. Keepign that in mind, ive sorted the high end with my main jet, then mid range, 4th clip as suggested by the instructions still wasnt as it should have been, I had a slight hesitation in the mid range then shot off. But the 5th clip still didn't quite feel right as it didn't pull as smooth as top range. So by putting the clip back on 4th groove and the third holes makes my bike pull like a train through the whole mid to top range. I am a newbie to these mods and this is my first one, so yes I do still get it wrong sometimes. I am just trying to share what I find as it might help someone in the correct direction that is in the same position I was.