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  1. #1
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    Default Shovelhead ignition troubles...

    So I took her out the other day, she was spitting, coughing, backfiring, black smoke. Took her home, checked the points, cleaned the carb out, it starts, but rough. It's kick only. Ran through the electrics, points are good, reads less than .125 at the condenser with the points closed, full 12 volt battery voltage when they're open. Is it just timing? Am I missing something? if anyone can run thru setting the timing, with pictures cause I'm dumb, that'd be great?

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    4400 pictures of Sporties and nothing on this? C'mon CC'ers, somebody must know something!!

  3. #3
    Allen
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    First, you can NEVER have enough pictures of Sportsters.

    Second, google searches work miracles when you've given up the "I'll figure it out as I go..."

    Third, I've found that there's always YouTube instructional videos that'll also give you step by step video instructions (if you have trouble following written instructions)...

    Fourth.... You should spearhead this one. Take pictures as YOU figure it out and create the THREAD you can't find for the next guy (in line) that's going to have to tackle the same timing process.... which, one day, may or may not be me!?!

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    Was it running fine and then suddenly started acting up? Do you have a fat, blue spark? Is yer battery fully charged and yer charging system working properly? Have you done any work on yer bike recently? Why do you think it's timing? I mean, it just doesn't change timing all by itself between rides. Did you get a bad tank of gas recently?

    So many questions...

  5. #5
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    From hawg rider on shovelhead USA ( can't recommend it enough for tech, SIGN UP>>>>)

    Here is static timing for points on a '70 and up Shovel in a nutshell...I'm gonna' tell ya' both ways...basic static timing in the "retard" position...and static timing in the full "advance" position which requires a slight modification:

    First, set you point gap to .018". Check it on both point cam lobes...the closer you can get it to equal the better, but the factory spec is within .004 of each other (but you can get it within .001" if you take the time to fully center the advance assembly on the end of the cam).

    Once the point gap is correct, bring the FRONT cylinder up on it's compression stroke...if you aren't sure, you can be sure by collapsing the front intake valve pushrod cover and watching the lifter...as you're pushing the engine through, that lifter will come up as the intake valve is opening...then it will go down as the valve is closing...when it's down, your front cylinder is coming up on it's compression stroke. Stop there!

    Look in the timing hole on the primary side of the bike (remove the plug first!)....VERY slowly, bump the engine over a bit with the kicker (or put the rear wheel off the ground and with the bike in high gear use the wheel to move the engine)...you are looking for the TDC mark on your flywheels (stock flywheels up through early 1980 have a small drilled dot low in the timing hole for the TDC mark and a vertical line for the advance mark....after early 1980 the factory changed the TDC mark to the vertical line...how's that for STUPID!)...when you find the TDC mark, position it so it's JUST inside of the timing hole...you want the back edge of the TDC mark touching the back edge of the timing hole, understand?

    OK, no go back around to the points. Connect a 12 volt DC volt meter with the negative lead to a good ground and the positive lead to the wiring terminal on the points....or use a simple test lamp wired up between a ground and the points. Turn on your ignition switch. When the points are OPEN, the meter will register 12 volts or the test lamp will light. When the points are closed, your meter will zero out or the lamp will go off.

    You want to set the points plate so the points are JUST BARELY beginning to open at the leading edge of the narrow lobe on your points cam. Turning the plate counterclockwise retards the timing, turning it clockwise advances it. As a starting point, loosen the ignition plate screws and turn the plate ALL the way counterclockwise so it's fully retarded and the points are closed (no voltage at meter or test lamp is off)...slowly turn it back clockwise until the very instant the meter shows battery voltage or the test lamp lights...STOP!! You want the points to BARELY be opening...so little that you almost can't "see" it...but you'll know they're open because of the meter or test lamp energizing. Lock the plate down. If you get it just right, you'll be able to just touch the top point with your fingertip and make the meter or light go off, then come back on as soon as you remove your finger.

    Verify that the flywheels didn't shift, the TDC mark is still in the leading edge of the timing hole...all set. Put the timing plug back in, put the point cover back on...have fun.

    That's it for the basic "static time in the retard position". Now, on to lesson number two, how to modify your point plate so you can very accurately time in the full advance position...which is a better method:

    Look at your point plate....you are going to drill a single 3/8" hole in it. First, you want to use a magic marker or sharpie to mark the general location of the hole. You are gonna' want to locate this new hole at the 7 o'clock position of the point plate, halfway between the outer edge of the point plate and the inner edge of that hole in the middle where the point cam sticks through. It doesn't have to be 100% exact, just eyeball it and put a little dot where you're gonna' drill it.

    REMOVE THE POINT PLATE OUT OF THE ENGINE!!! DO NOT drill it in the bike!! Take it out and drill a nice 3/8" hole right through the plate. Once it's drilled...now you can put it back in. Install it in the engine and you'll note that you can now see the advance weights through that hole...not only will you use that hole for timing the bike in the advance position...you'll also be able to use that hole to squirt a little lube on the advance weight pivot pins every once in a while!

    Timing is basically the same as described above, with a couple of slight changes. First, set the point gap as described. Then roll the engine over until the front cylinder is just coming up on it's compression stroke....now look in the timing hole and find the front cylinder ADVANCE timing mark on the flywheel, locating it exactly dead center in the timing hole.

    With that timing mark centered in the hole...the small lobe of the points cam should be coming around towards the point rubbing block. The idea is you can now put a small screwdriver or scribe or awl through that 3/8" hole you drilled in the plate, using that tool to move the advance weights outward to the full advance position.

    OK, now you're ready...this is just a little teensy bit tricky. What you need to do is move the advance weights "out" so the advance assembly turns the points cam to their fully advance position and hold 'em there (sometimes it helps to have a friend hold 'em, but you can do it all by your lonesome, just practice). Once the point cam is twisted to its fully advance position, you want to points to be set to where they are just beginning to open the points. Turn the points plate until the points rubbing block just makes contact with the leading edge of the points cam...the very second the test lamp comes on (or the meter registers 12 volts) STOP!!. That's what you want...lock the distributor down. To check it, turn the points cam to its fully advanced position and when it stops the lamp should just come on...the points should be barely open...you should be able to just touch the points with your fingertip and make the lamp go out. It may take you a couple of tries to get it exact the first time, but with practice you'll find it only takes a few minutes for the entire process.

    Using the "advance" static timing method....you CAN ACCURATELY time any points ignition. I have done this too many times to count over the past 30 years...and have confirmed with a timing light...it is as accurate as it gets. If you have a very high compression engine...you can slightly retard the timing by moving the advance timing mark halfway between the center of the timing hole and the front edge of the timing hole (towards "front" of the engine)...this will retard your timing about 2.5 degrees more than stock and it will reduce the potential for detonation, yet still run and start just fine.

    Print it out and give it a try...it's easier than it may sound. The key is to take the time to ensure the points are JUST STARTING to open at the leading edge of the points cam...this applies to both static timing methods, either retard or advance.
    and then this video

    http://www.youtube.com/watch?v=mKVh4pbyh2A


    ltr Pat

  6. #6
    ARBY
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    Quote Originally Posted by Weepster View Post
    So I took her out the other day, she was spitting, coughing, backfiring, black smoke. Took her home, checked the points, cleaned the carb out, it starts, but rough. It's kick only. Ran through the electrics, points are good, reads less than .125 at the condenser with the points closed, full 12 volt battery voltage when they're open. Is it just timing? Am I missing something? if anyone can run thru setting the timing, with pictures cause I'm dumb, that'd be great?
    Black smoke? Sounds like a rich condition. You sure your choke isn't stuck open slightly?

  7. #7
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    Try a new condenser, they can go bad and do kinda what you say

    Bob

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    Carbs are critical so if you didn't check float adjustment and ensure the needle actually seals to the seat I'd do that. The black Viton needle tips can harden and show a ring-shaped indentation instead of being a nice conical shape from base to tip.

    You can also (do this outdoors for obvious reasons) remove the float bowl, hold the float fully upwards, and gently lower it to see when fuel flow starts. If in doubt, it's better to have the float close a bit early than late.

    I always keep a full carb rebuild kit on hand as well as points and condenser. (I don't buy toilet paper by the sheet either. Worst case when I die there will be some "bench stock" at the estate sale but I got decades of convenience!.)

    An ancient trick to check spark quality is to hold two (KNOWN GOOD) spark plugs together using a worm drive metal hose clamp. Standard Harley coils fire across the coil hence will spark at both plugs and the plug bodies don't need to be grounded when testing. (I tack weld mine together instead of using a clamp.)

    Post which carb you are running so others can be more helpful.

    BTW there is good reason for the popularity of either replacement Allen head or extended custom "knob type" float bowl screws.

  9. #9
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    Check your ground.

  10. #10
    ARBY
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    Quote Originally Posted by Dennis53 View Post
    Check your ground.
    That too. Some folks forget that the ground is just as important as the hot.

  11. #11
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    The winner is Greybeardbob (and me), a bad condenser. Thanks for the replies. I love sportster pics too, the google machine is missing that shovel info as is youtube, and I will spearhead this. It's an SU eliminator carb, part finicky, part simple as shit. I knew it was timing because it rode fine one day, terrible the next, carbs don't go bad that fast. I don't like throwing parts at an unknown problem, but an old-timer said ' just try the condenser, they cost $3'.

  12. #12
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    man I missed this thread, I was gonna say condensor.. I see a lot of bikes in the shop where people swapped out the points with new ones, but were not careful when connecting the wiring in the unit, the prongs weren't perfectly horizontal and they ended up grounding out when they put the points cover on, usually with no cardboard.paper gasket. The showclass one just did my buddies shovel in

  13. #13
    xllance
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    Quote Originally Posted by Weepster View Post
    The winner is Greybeardbob (and me), a bad condenser. Thanks for the replies. I love sportster pics too, the google machine is missing that shovel info as is youtube, and I will spearhead this. It's an SU eliminator carb, part finicky, part simple as shit. I knew it was timing because it rode fine one day, terrible the next, carbs don't go bad that fast. I don't like throwing parts at an unknown problem, but an old-timer said ' just try the condenser, they cost $3'.
    Well you said it was the condenser, then you said it was timing. I know it all has to do with timing in a way I guess. But when someone says they have a timing problem, to me it means the points plate isn't in the right position, causing the plugs to fire at the wrong 'time'. Maybe it's just me but words mean things !

  14. #14
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    Sorry Lance, didn't mean to use the wrong words, but thanks for the constructive criticism. I'll be more careful next time.

  15. #15
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    Glad we got you going again.

    Bob

  16. #16

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    This thread is great. That repost from Misfitcj fixed me up.

  17. #17
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    there is no difference in setting the points in and Ironhead and a Shovel or any other HD. the plate orientation is turned 90 degrees between a sportster and Big Twin but the actual process is exactly the same.

  18. #18
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    I was having trouble starting the shovel after removing the timing plate, so I searched and this thread came up. I used the "full advance"method. Worked like a fucking charm. Before, the bike was back-firing coughing, spitting, putting out black smoke....after following the above article, she runs "like butter".

    Only thing I noticed was the hole needed to be drilled more toward the cam side of the plate and a little higher than the 7 o'clock position.

    Thanks for the info.

  19. #19
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    Quote Originally Posted by FooDog View Post
    I was having trouble starting the shovel after removing the timing plate, so I searched and this thread came up. I used the "full advance"method. Worked like a fucking charm. Before, the bike was back-firing coughing, spitting, putting out black smoke....after following the above article, she runs "like butter".

    Only thing I noticed was the hole needed to be drilled more toward the cam side of the plate and a little higher than the 7 o'clock position.

    Thanks for the info.
    Can't you just twist the points cam counterclockwise as far as it will go to get full advance, rather than pushing the counterweights directly through a drilled hole?

  20. #20
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    Quote Originally Posted by alfajuj View Post
    Can't you just twist the points cam counterclockwise as far as it will go to get full advance, rather than pushing the counterweights directly through a drilled hole?
    Yes. The only real advantage to the hole is lubing the weight pivots without removing the timing plate, which is actually an excellent advantage.
    I run points on both of my Evolution motors.

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