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Ignition/Tuner/ECM/Fuel InjectionNeed advice on ignition issues? Questions about a tuner? Have questions about a EFI calibration or Fuel Injection? Tips on Engine Diagnostics, how to get codes, and what they mean. Find your answers here.
Hello All,
I recently got a dead bike up and running. I am no mechanic but I do enjoy tinkering on my off time. This one took a bit. Was a bike that hadn't run for a year. Sat for 2 years in my garage as I slowly tinkered.
Problems: Would turn over, rarely sparked, would backfire through carb occasionally, would give big "woompf" and fire from exhaust, never actually ran. Solution: ordered dyna tech through advice from other forum, then had to order mechanical advance. Put the advance on with the stock springs, put the dyna tech on at around 3 o'clock position. It runs!!
Took it on a trip around the block. Backfires almost constantly if I twist my wrist enough. Back fires occasionally at idle but I think I got that taken care of by adjusting the settings on my s&s carb. I'm thinking it's the timing. Could it possibly be the springs on the mechanical advance? Do they need to be the heavier ones? Wife chased me off for making too much noise before could keep trouble shooting.
Sorry if this has been posted before, and I would continue on my old forum but it seems the site was shut down.
Someone must of rigged up a different ignition for your bike. The original ignition module is a one-piece unit down in the nose cone part number is 32465-98b.. Also I would get a factory service manual so you can learn how to time it properly. Bike looks a little rough but with some TLC you should be okay.. Good luck..
Just saw this on eBay and for the price it's worth it to give it a shot.. Not only that you can get your timing dead nuts on..
With a S&S carb, who knows what the jetting is, could be too rich or too lean causing the backfire. May want to find a CV carb with standard jetting and see if that makes a difference.
As you said could also be the timing but fuel is always suspect.
With a S&S carb, who knows what the jetting is, could be too rich or too lean causing the backfire. May want to find a CV carb with standard jetting and see if that makes a difference.
As you said could also be the timing but fuel is always suspect.
The S&S E is one of the easiest carbs to work on and extremely reliable.., either a .028" or .0295" for the intermediate and maybe a 66 to 70 on the main.. easy peasy.....
Plus the guy just got the bike and he probably doesn't even know if the motor's been built or anything.. So start changing something like that and you're probably adding to more issues...
OP, check to make sure that the intake seals at the cylinder heads aren't sucking air.. That will definitely create issues with coughing spitting and sputtering..
Last edited by 98hotrodfatboy; Nov 5, 2023 at 06:09 AM.
Can't really help with your project Nick but quite impressed with it and what you have already accomplished on it. Just helping keep your post on top.
Would like to say also, 'Welcome, hope you enjoy your ride here'. And only as a suggestion, make your next new post over in the new member welcome area to say hello.
is the installation of the dyna s correct? correct system for the coil?
used the correct timing mark
held the adv in full when setting it up. springs only set curve and stock brings in full advance around 2.8k
the ultima system is more friendly with the timing led. i run a compu-fire dual system on my 74ch been there since 1975 idle to 7.5k and nearly 200k on the clock. it uses the mechanical adv.
there is one kirk on some systems in that it was originally for the BT and in order to use it on the XL, the module is installed upside down or 180*
[QUOTE=98hotrodfatboy;21443012]Someone must of rigged up a different ignition for your bike. The original ignition module is a one-piece unit down in the nose cone part
It was stock. I ordered a used stock part and buttoned that up and still had the same issue as no start/rare spark. My original ignition module you could turn it and it would light up at correct timing. But as I would crank, the led would flash. Trouble shooting guide says bad part. The replacement OEM part had same issue. Could have been 2 bad units but idk. I haven't done static timing with manual yet.
Bike is rough. $500 buy just to putt around on island.
With a S&S carb, who knows what the jetting is, could be too rich or too lean causing the backfire. May want to find a CV carb with standard jetting and see if that makes a difference.
As you said could also be the timing but fuel is always suspect.
I had opened up the carb and cleaned it. Forgot to record what the jet sizes were. Had an issue of carb overfilling and bought a rebuild kit. Now carb doesn't spill gas. I'm no expert but I believe I adjusted the carb settings to be neither rich or lean. I do have a spare CV carb I could not on and try.
So I putt around for about 30 min today. Lots of elevation change here in Guam. Going up the hills I did not have a lot of power at all. I was climbing in 1st gear most of the time. If I twist my wrist too much, backfire.
I'm thinking my bike don't have any baffles. It's loud. I don't have a working tach (ordered an induction tach). I've never owned or ridden a harley. Maybe I'm mistaking what 1k rpms sounds like? I turned up the idle and we'll see tomorrow if she rides better. But all my old bikes the idle was basically as low as you could get out without it dying.
is the installation of the dyna s correct? correct system for the coil?
used the correct timing mark
held the adv in full when setting it up. springs only set curve and stock brings in full advance around 2.8k
the ultima system is more friendly with the timing led. i run a compu-fire dual system on my 74ch been there since 1975 idle to 7.5k and nearly 200k on the clock. it uses the mechanical adv.
there is one kirk on some systems in that it was originally for the BT and in order to use it on the XL, the module is installed upside down or 180*
How do you hold advance in full? Sorry if that a dumb question
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