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    Default What Gives? Hard Starting!

    Before someone jumps on me, I have looked and looked and looked some more and not just chop cult but all over the net hoping for some golden nugget but nothing. I am at my whits end! I have tried everything I have found, to no avail. So the bike is a 82 FXS I picked up not running. Tore it apart it has Truett and Osborne Flywheels, S&S rods, 4.5" Stroke, +30 over 3 5/8 big bore just freshly matched to S&S forged pistons, Andrews AB grind cam, Hydraulic lifters, with Andrews adjustable push rods. S&S super E with 28 pilot, 72 main, 2.25 turn out on fuel screw, points (originally), kick only (ya, I know), brand new 8 cell Anti gravity battery and it is wired so the head light isn't on during starting, but the tail light is. The thing is a MF'r to start but when she does start she runs beautifully! The really weird thing is when she does come to life I barely kick it, I am talking about the kicker arm 3/4 the way down and just barely any weight slowly, I hope that makes sense. Obviously It doesn't work all the time or I wouldn't be writing this. If I give her hell, a full kick to get the flywheels spinning she doesn't even pop, fart, or make a sound, nothing, nada! So what I have tried? First I kept reading people arguing between points and electronic ignition. I had points because there seemed to be more people saying they were better for kick starting, I adjusted the air gap and timed it probably 10 times, no change. I tried retarding it and advancing it as well still nothing. The other half of the crowd, the electronic ignition crowd, swore by the Dyna S, so I dropped some dough and bought the kit with the electronic ignition coil. No better and I even tried advancing it and retarding it as well. When I timed it with a light, running, she goes straight to the full advance mark at 2k rpm with a light and I used a dial back light to check the idle timing marks and both are spot on. I checked continuity of all the wires on the ignition circuit looking for any breaks or opens and there are none that I can find. I have looked for intermittent spark with spark tester and cannot seem to find anything. I tried 2 new sets of plugs all gaped to 38. I kind assumed it wasn't the ignition after trying to time it so many times with two completely different ignitions and sets of plugs. I then went to the carb I started with a 29.5 pilot and a 72 main then went to a 31 pilot and no better. I then went to a 28 pilot and a 72 main and it was no better. I adjusted the fuel mixture screw accordingly every time. I tried 1 squirt then kick, 2 squirts then kick, 3 squirts then kick, then 1 prime kick, then 2 prime kicks, then 3 prime kicks, and then every possible combination of the squirts, prime kicks, with choke off and on at different positions, and nothing. I did a compression check and it is about 106 psi both front and rear leak down is less than 1% with the fresh jugs and pistons. I tore open the cam to check timing and it is spot on. I have adjusted the push rods a half dozen times and now need new o-rings as the front exhaust is leaking from doing it so many times! I am usually pretty good at dialing in my shovel head kickers but this is the first one I have had with the the big bore kit on it. Thoughts ANYONE!

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    If your leak down is "less than 1%", you need a new gauge. That number is all but impossible to achieve, even with zero gap rings.

    28 intermediate jet is too small. 29.5 or 31 will be the sweet spot.

    You did not say what type of hydraulic tappets you have, but I suspect that may be one of your trouble spots.

    The Dyna S is hands down the best kick start ignition out there, because it delivers good spark down to almost zero rpm. Depending on your plug wires, you may want to close the plug gap up some. Warning: Accel wires with the long coil connectors will short to the coil cover. Hard to spot. The advance unit movement may need to be restricted to give a more advanced timing at kicking speeds.

    Intake manifold leaks will play havoc with kick starting. The late shovel rubber bands are THE worst for not sealing.

    That's all off the top of my head.
    Jim

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    Before I get into what I think it is...... Since it's a FXS why not use the electric starter??????? I don't think you said..........


    Or are you just wanting to kick it to start it??????????

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    Thanks for the quick reply!

    I have acess to another Leak Down tester, I will try that one and let you know. I suspect it is going to be good with it being that high on mine.

    Ya, I started with a 29.5 and then went to a 31 and neither seemed to help.

    I believe the tappets are stock, I a cannot find any markings on them, I will order some solids and see if that helps.

    The plug wires are Taylor and I have no coil cover. I did try to advance the timing plate to see if that would help but it didn't. I am not familiar with restricting the Advance unit. How do you do that?

    I forgot to mention I did check for intake leaks and initially had one but I have since fixed it and cannot find another.

    Thanks again Jim, at least it's a direction to try something.

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    @Tattooo It never came with a primary and i just put an open primary with no E start on it and I just want to kick it. That would have been easier though, but I was trying to keep the cost down but that seems to be out the window now. So what do you think it is? I am up to try almost anything.
    Last edited by sgilliesjr; 12-09-2019 at 9:15 PM.

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    If the tappets are stock hydraulic, try adjusting them 1 1/2 turns up from fully bottomed out. Even if they are half worn out, they will function well there.

    To restrict the advance unit, press some brass hobby tubing over the stop pins (the pins that go in the holes in the base). Then adjust for full advance in the usual way. Your cranking and idle timing will be a few degrees higher. This works GOOD on shovels with Super Es and any kind of cam above stock.

    You should work on the number of prime kicks, ignition off, choke full on, and NO squirts. The motor should be consistent when cold. Hot starting should be, switch on and kick. It's the not cold, not hot condition that gives me the most trouble, and I've had my bike almost 30 years. Still learning.

    Jim

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    Mine is gas on, 3 primes (not 2, not 4), no acc pump, no squirts. An honest 1 to 2 kicks start.

    Took me forever to figure that out.

    They're all different, learn your sequence dont give up
    Last edited by markwade74; 12-09-2019 at 9:58 PM.

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    Dude! Jim I think I love you! Stopped by Ace Hardware picked up some brass tubing and pressed it onto the ATU stops and what do you know! I kicked it probably 20 times in a row and it started every single time! No prime kicks no squirts just choke on! If you are ever in Cave Creek AZ let me know I owe you a beer!

    Thanks Again!

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    Quote Originally Posted by sgilliesjr View Post
    Dude! Jim I think I love you! Stopped by Ace Hardware picked up some brass tubing and pressed it onto the ATU stops and what do you know! I kicked it probably 20 times in a row and it started every single time! No prime kicks no squirts just choke on! If you are ever in Cave Creek AZ let me know I owe you a beer!

    Thanks Again!
    Can you snap a picture of what it is your doing ? I can't wrap my head around the brass tubing thing .

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    Quote Originally Posted by 47str8leg View Post
    Can you snap a picture of what it is your doing ? I can't wrap my head around the brass tubing thing .
    I can explain a little more, no pics though.

    The advance weights have a split roll pin that engages a hole in the base. That is what restricts the weights' movement in both directions. By pressing a piece of tubing over the split pins, you increase their diameter and consequently the distance the weight can move is reduced. You can also make solid pins to replace the split pins, and make the protruding part any diameter you wish.

    This is just one way of tuning an advance unit. There were any number of kits to trick out distributors in cars back in the point and coil days. You can also shave the weights or change the springs (if you can find any these days).

    What this does is change the angle of movement of the advance unit . A standard HD unit should have 15 degrees of movement (thirty crankshaft degrees). If you reduce that movement by two or three degrees, and your advanced timing stays the same, the cranking and idle timing will be higher.
    Example, with a stock 15 degree advance unit, at 35 degrees BTDC total timing, idle timing is 5 degrees BTDC. With your modified 13 degree advance unit, idle timing changes to 9 degrees BTDC. A little crisper idle, better off-idle response, and for the OP, easier kick starting.

    Jim

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    Quote Originally Posted by JBinNC View Post
    I can explain a little more, no pics though.

    The advance weights have a split roll pin that engages a hole in the base. That is what restricts the weights' movement in both directions.

    Jim
    I've never thought of that...... I thought his problem was timing...... But that was an easy fix...........

    Man that's an awesome trick...............

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    Sorry I have it on the bike right now but I have an exatra ATU laying here so per Jim's suggestion I used a tubing cutter to cut the brass tubing in the pic to the same length as the roll pins on the back of the ATU. I put the brass rod on one of the roll pins just to show where it goes. I did take the weights off and did it on a bench not assembled like it is in the pic! Click image for larger version. 

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    Last edited by sgilliesjr; 12-10-2019 at 9:04 PM.

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    Quote Originally Posted by Tattooo View Post
    I've never thought of that...... I thought his problem was timing...... But that was an easy fix...........

    Man that's an awesome trick...............
    Wow, so you can teach an old dog new tricks.

    Might have to give this one a try.

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    Quote Originally Posted by Akamm47 View Post
    Wow, so you can teach an old dog new tricks.

    Might have to give this one a try.
    Yes sir you sure can........... And I don't mind admitting that I didn't know something...... LOL

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    Thanks for the pics of your advance unit mod. I have an 84 Softail with a 100 inch Evo thats been a miserable bitch to get started cold. Can't believe this mod solved my problem.

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    Quote Originally Posted by Rich54 View Post
    Thanks for the pics of your advance unit mod. I have an 84 Softail with a 100 inch Evo thats been a miserable bitch to get started cold. Can't believe this mod solved my problem.
    It's just part of tuning. Tuning involves all the systems that effect how the motor runs. (Not to mention chassis tuning, not the subject of this thread.)

    In this electronic age, we can often forget that mechanical parts can be tweaked. Back in the early days of hot rodding cars, ignition mods were a big thing.

    I've been doing this particular tweak for over 20 years, mainly to improve idle and off-idle performance of shovels with Super Es (and Bs). The better kick starting was a welcome by-product.

    Jim

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    so would you modify just one pin and test or just do the two in one shot

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    Quote Originally Posted by 55reaper View Post
    so would you modify just one pin and test or just do the two in one shot
    Do both, the weights work in tandem.

    Jim

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    Quote Originally Posted by JBinNC View Post
    I can explain a little more, no pics though.

    The advance weights have a split roll pin that engages a hole in the base. That is what restricts the weights' movement in both directions. By pressing a piece of tubing over the split pins, you increase their diameter and consequently the distance the weight can move is reduced. You can also make solid pins to replace the split pins, and make the protruding part any diameter you wish.

    This is just one way of tuning an advance unit. There were any number of kits to trick out distributors in cars back in the point and coil days. You can also shave the weights or change the springs (if you can find any these days).

    What this does is change the angle of movement of the advance unit . A standard HD unit should have 15 degrees of movement (thirty crankshaft degrees). If you reduce that movement by two or three degrees, and your advanced timing stays the same, the cranking and idle timing will be higher.
    Example, with a stock 15 degree advance unit, at 35 degrees BTDC total timing, idle timing is 5 degrees BTDC. With your modified 13 degree advance unit, idle timing changes to 9 degrees BTDC. A little crisper idle, better off-idle response, and for the OP, easier kick starting.

    Jim
    shit i got to remember this one

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