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As the others have already posted, you can really chase your tail on this sort of stuff. Basic problem is not that the engine will burn more fuel, but that the original airbox / intake etc cause more vacuum that pulls the correct amount of fuel from the float bowls. Going to pods gives you less vacuum in the carb venturi for the same engine speed, and consequently pulls less fuel up from the float bowls, hence the weak mixture. As a test / see, you could lift the needle in main jets by dropping the circlip two notches, setting the float height a couple of millimetres higher, turning the idle jets in by 1/4 from standard setting and using resisted spark plugs with resisted HT caps as well.It would push it toward where you need to be and at least see if it improves without significant cost. Edit;- also make sure the plugs are at their minimum specified gap too.
I have messed with jetting etc for some time on the CR750 Rep (road use) and now got it pretty much spot on across the range. I can quote what my settings are but there are so many variables on each build. I had no choice when building a CR Rep as you can't have a CR Rep with std airbox and exhausts but on the K6 Cafe racer project I'm building I've re-fitted the airbox and std exhausts (which was a pain as the previous owner cut the airbox and exhaust brackets off and I had to weld them back on!) to make the carb set up easy - ie, standard..One of the main issues MarkCR750 pointed out was the step from the pod to the carb body that the pods create - ruining the smooth airflow. Mark adopted the standard airbox rubbers to the pods to maintain the airflow I think (there's a post on here somewhere). Marks build uses PD carbs though I think.My CR runs standard carb with foam pods (no step to carb bodies) and ended up with 135 mains, 45 primary jets (I had to drill 40's out to 45 as no longer available), air screws 1 3/8's out and needle on middle groove. I'm running 4 into 4 race exhausts with K0 baffles in and standard compression 836 kit. This may not help as you will be running a diiferent combination but will give you an idea - took about 10 changes of combination to arrive at the right setting that gives a reasonable tickover, smooth step free mid range and good top end.Hope that helps
Quote from: K2-K6 on May 12, 2020, 08:27:09 PMAs the others have already posted, you can really chase your tail on this sort of stuff. Basic problem is not that the engine will burn more fuel, but that the original airbox / intake etc cause more vacuum that pulls the correct amount of fuel from the float bowls. Going to pods gives you less vacuum in the carb venturi for the same engine speed, and consequently pulls less fuel up from the float bowls, hence the weak mixture. As a test / see, you could lift the needle in main jets by dropping the circlip two notches, setting the float height a couple of millimetres higher, turning the idle jets in by 1/4 from standard setting and using resisted spark plugs with resisted HT caps as well.It would push it toward where you need to be and at least see if it improves without significant cost. Edit;- also make sure the plugs are at their minimum specified gap too.If you use resisted plugs and resister caps that with give a weak spark
Quote from: brodsord on May 12, 2020, 06:16:25 PMChoke lever*F@cking iPhone Sent from my iPhone using Tapatalk.
Choke lever*F@cking iPhone Sent from my iPhone using Tapatalk
DS have DR8ES listed as NGK plug spec for the K5. It's worth fitting the equivalent in higher heat range while you work on the jetting. So DR9ES as they are more resistant to the plug tip going over temperature during your mixture exploration phase. It reduces the risk of pre-ignition that could cause damage to the engine.
Does the bike have red or black NGK plug caps fitted?If it does those are the wrong type plugs.
Good news that you've got it running more as you want it.I'd agree that it's a little lean, but not drastically as the earth bar is "milky coffee" tone.Definitely fit ngk 9 grade plugs to bring the tip temperature down. They have wider heat transmission path to more easily get the heat out of and away from the electrode. It's this that ultimately causes a holed piston as if it gets too hot then it ignites the mixture prior to timing point. Classic "pre-ignition" that you can't feel until it's too late.With the needles up at maximum you've no more to add on mains so it would look wise to go up to 110 jet size that would give you more safety with the needles set as they are. That should give you a decent baseline for longer assessments to be made along with reducing risks.
Blimey, that's running lean. You will burn a hole in your pistons and burn the face of the valves if left like that.