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i was havein alot of trouble with my lectrons too for a while. i ended up useing fbg needles in mine and most of my problems went away. they are not slotted like the packerd ones and they were muck easier for me to tune. just a thought
 
I know most of you guys are drag racers but every since I got this lectron its got a bog or miss after landing from a jump. Have 2 buddies that have the same carb on 4 strokes and dont have the problem. Could my float height not be right? Sometimes when I rev it up I get a little fuel out of the right side vent. Tried it with the stock and billet bowl.
 
Ok here is the problem im having. on my 670 cranker 45 packard lectrons (gas).

Dennis set them up they where about 1 1/4 turns on the needle to rich but the power jets at that time was 3 turns out.



so heres the question. with the needles turned 1 1/4 turns leaner then where I got the from pakard and the power jets open 1 1/2 tunrs. its still rich on bottom and just about right on top.



coming out of the hole the power jets are in use. so anyways would it help to richen the needle back up and close the power jet down to around 3/4's out. Dennis did tell me I should end up with the power jets open mybe a half a turn.



cause where im at right now if I close the power jets anymore it will be to lean on top
 
ok I talked to dennis get it figured out.

I have one more question. I have one more turn left on the idle screw and im taped out. anyways the question is the right cylinder seems to be richer and smokes more with the carbs set up the same. and when you shut it off it smokes to. but the plug looks leaner
 
I have one more turn left on the idle screw and im tapped out.




You could take the screw all the way out and plug the hole with 5m .90 set screw..and use the adjustment on the cable to set the idle rpm.



its by far the easiest way. By using the idle screw..it only puts slack in the throttle cable(which is somthing you dont want.



the metering rod is what ultimately sets the idle mixture..not that little brass screw



that goes for any motor with a lectron, single, twin, triple, 2 or 4stroke, Banshee, vespa, crankenjunk, Volkswagon..stationwagon..



So...having said that:



if youre using the idle screw period.., you have one more varible in the equation that you could easily do without
 
these things arent rocketscience





Before you ever crank the bike up, there are a few things that need to be done so youll be able to tune them to the bike.



Things like..(1)Indexing the rods to see where the taper is.



It also helps if you (2)sync the slides. You cant possibly expect your machine to run even close to right if your slides are all jacked up. They have to be level with one another..and they have to be strung on a tight cable. You can use those little brass fittings in the top of the carb to set the slide height. You can use that little arch in the back of the slide as a visual reference(THATS WHATS ITS THERE FOR) You can also use the #2 adjusters on the cable. Without syncing the slides first..youve got nothing..



that (3)brass idle screw is a waste of time and material and only confuses the cable. get rid of it and dont look back.(plug the hole first)





WTF is indexing..??



Its pretty hard to explain if you dont understand the concept behind the how the rod meters the fuel through the carb.

If you index the rods, that will tell you how much to take off the bottom of the longer of the two, or 3, or 4 rods so when you DO measure the length, (ex.)48.5 in the left..meters the same amount of fuel as 48.5 in the right..



For example, if the rods arent indexed properly(AND OFTEN TIMES THEY ARE NOT..!!) The metering face in the left carb is at a different location than the metering face in right carb...EVEN WHEN THEY MEASURE THE SAME LENGTH sticking out of the bottom of the slide.





Good things to know



There are three different generations of rods



FirstGenRods only work in carbs 40mm and below. Gen2Rods(marked by the letter "L") only work in carbs 44 and below. Gen 3 rods(XL) work in carbs 48 and below







I feel that the main reason dennis uses XL rods in smaller carbs is because it gives that extra little bit of tunability to the carb by creating a lean condition, and the way you tune out of that is to rub sandpaper on the upper portion of the rod close to the threads in order make rooom for more fuel at an idle.(please dont grind your rod with sandpaper)



It also helps if you measure in inches, 1.81, 1.85, 2.0, all good start points depending on which generation rod you have..



Finally..



(4)Get a cable that has a built in adjuster next to the throttle. I promise you, It makes your life so much easier.



Please dont call dennis and badger him because your bike doesnt run right..hes a busy man. IF you have to call him, then ask sensible questions like:



How important is it that my rods are indexed properly..?(Can you tell me how to check this for myself..?) and he will..it involves a dial caliper

How important is it that my slides are sync'd..?(and tips on doing so)

How important is the idle screw on a twin and higher..?



All this...Is the Tip of the Spear..!! Nothing, not temperature, not altitude, not fuel oil ratio, tire pressure, or paintjob on your sexy blubbering, non running machine makes as much difference to it's performance as whats listed above..



1)Index your rods..if you dont know how, ask your builder

2)Sync your slides and make them exact

3)DX the idle screw and plug the hole

4)Get a cable with an adjuster on all three ends(twin)

Peace..yo
 
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i know this thread is not about Dennis Packard, but....i just got off the phone with him (great guy, btw) and he was extremely helpfull. i ordered me some 38/40 Lectrons from him, should be here in a few days, woohoo, but he asked me for the info on my motor and elevation. he was very clear as to how the carb was going to be set up when they arrived, and what adjustments may need to be done and how to go about doing them.



as stated in a earlier post, there is no need to call and badger him, if you listen to what he says when you are making the purchase, you should be fine. these will be my first set of Lectrons that im going to run, dont really know much about them, but i feel confident that i should be able to make the transition from Kehins to Lectrons without an issue.
 
QUOTE (PumaClimber @ Apr 24 2009, 09:10 PM) index.php?act=findpost&pid=39755I have been trying to tune a 44mm lectron on a 431 250r. I too was getting the hang in the rpm's and usually that means its lean on a Kehien. So I kept richening it up and it got worse. So I leaned it out and the hang is gone. Must be backwards from a Kehien.





I have some brand new (pumper) Packard Lectrons that have been complete junk...burned 3 plug straps. Took the carbs to Packard himself at Gilbert and he said the needles and floats were not set right (were supposed to be ready to run out the box.) Another pass and another burned plug strap. Took them back to him and he drilled out the bell on the end of the powerjet (have no ideal how the hell this could help them flow very much more fuel.) Made another pass, and it didn't burn the strap, but it did not run good at all...still very lean. Drilled the powerjets and barbs out to 0.096''..now it's plenty rich on the right side (the one that was burning straps), and damn near burned a strap on the left cylinder. THeir may be some trash in the carbs causing that, but either way, I'm about fed up with them. For 0, or whatever the hell they cost, they should have been very close out of the box. Anyone want to trade for some good 'ol 39 PWKs (gravity fed) with billet bowls?




UPDATE on this situation. I can't fully blame the carbs for my problems, because I had a leaking base gasket. I had the engine completely redone, switched the Lectrons to gravity and dyoned the motor Saturday (10 mil Cub.) I got an unimpressive 103 hp out of the Lectrons [my unported 421 Cub made 100 hp all day long on this dyno]. Through some PWKs on there with the pjs wide open and got (still unimpressive) 107 hp. Another set of PWKs drilled out a little more with the pjs wide open and got (still unimpressive) 109 hp the first pull.



Anyone want to give me some alky 39 pwks + money for these Lectrons with billet bowls?
 
What is the leanest length you should go on lectron carbs. I know Dennis told me 48.5 is neutral on the 45 lectron. Plus 3/4 rich. When I raced last it kind of was boggy on the bottom end. I reset it around 49.2. So its a little leaner now. Also will being lean on the bottom end, should this pick up 60ft times?
 
nothin against anyone that runs lectrons but my god i hate these freakin carbs!..lol..i have tried all year long to get them right and ran me ragged,i took em off and installed 41mm mukunis and the bike bout ripped me off of it!..no chit..its cost me well over 1k tryin to find the gremlin and it ended up being the carbs so if you have good luck with em congrats but my azz will NEVER own another set as long as i live..lol..and i aint no cherry when it comes to workin on these junkers ive done it for a few years now and can tune pwks,mukuni pretty simple!..jmo on this..
 
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