[Bassman]

Hey all,
Kinda new here. I have an '84 ironhead sporster. I got it feb of last year and have yet to ride it. Up until recently, it would fire right up, but within minutes start backfiring through the front pipe and foul the plugs bad. Black sooty. I tried adjusting the carb (an S&S E) new plugs and wires, everything. I got it to go 30 feet once before it backfired and quit. But the next day, after replacing the plugs again, she fired right up. Readjusted carb so she wouldn't run so rich. Fast forward to last month. Still haven't ridden her in over a year. My buddy gets a '77 sporty that runs pretty good but leaks out the rocker. He changes the rocker gasket, and it starts running exactly like mine! He adjusted the front valves and it runs great, so he comes and adjusted my valves too, thinking we had the same prob.
Now my bike cranks but won't even start. I have readjusted the valves over a dozen times in the last 2 weeks. Still nothing. Played with the timing. Nothing. Just cranks. Makes a kind of "plut plut" noise from the carb when I am cranking her, but will not try to start, even with starter fluid. I even read on this forum about if it could be 180 degrees out, to switch the plug wires around. Still nothing. I am running out of ideas and hope.
This is my first Harley. I am proud of her. I am not very experienced with bike engines. But a year and a half of just looking at her, (it is a gorgeous bike) but I have pushed her much more than she has ever been ridden. I am scared the valve job my buddy did may have bent a valve. No money to get that fixed when the local dealer wants 66 bucks an hour. I am just an average working Joe with bills to pay and no platinum card to plunk down.
To me Harleys are my favorite. I have always wanted one. Worked overtime and saved my ass off to make this dream come true, only to sit and watch my friends ride while I sit each weekend working on mine only to fail. WTF am I doing wrong? Someone please help. If I miss this season, next season will be over 2 years she has sat. I am losing hope. HELP???

[whacker]

I would have the compression checked...then check ignition timming,I have a 75 sportster,and it runs great ...Good luck...

[Lucifer]

Make sure you have a bright sharp blue spark at the plugs,any orange and its not hot enuf. Check your coil.If timing was 180 out in wouldn't start at all,it would fire on the exhaust stroke not the compression stroke.
You do have a shop manual,right?? If its electronic ignition you should have 2.8-3.1 ohms resistance on the primary of the coil. i can't remember what secondary resistance is right know .(maybe 15,000-20,000 ohms) Check the book.
I think around '81 all bikes went to electronic ign, but if you have points and condensers and your coil checks OK change condensers, they can go south at any time and always look fine.
If you have air,compression, spark and fuel it should fire up. Take a deep breath to make sure you got air

[Bassman]

Well, I took the coil off and I am going to have it checked tomorrow on the way to work.
According to the clymer manual, the primary on the coil is supposed to be 4.7-5.7,
With the secondary being 16,500-19,500.
My ohm meter only has reading settings at RX1K and RX10. But the Manual states to set it at Rx1 for reading primary and RX 100 for secondary. Not available on my meter. So I will take it in to a local shop tomorrow and see what they have to say.
My spark is actually white/yellow and not very big. I am wondering, since I set the pushrods a million times already, that maybe it won't start at all just because of the coil not putting out enough spark. Although one dude says as long as it gets ANY kind of spark, it will fire. I know nothing of electronics on bikes or cars. I also checked to see if the rods are bent somehow, but they all look brand new. As for the lifters, I have no idea what the previous owner had put in there. He had the bike rebuilt not long before I got it. Maybe a year, but it doesn't say in the paperwork what lifters were used. Is there a way to tell without tearing down the motor?
I have yet to check the compression. But that is on the way probably tonight. I would just love to ride her once before the snow flies.
I don't have a lot of experience wrenching on them, but they sure are fun to ride. Thanks for the help so far.
Later

[Bassman]

PS,
She is electronic ign. No points. Everything looks new.
Oh I did take a deep breath, I am just holding it in while waiting to fix this bike. lol

[Lucifer]

Set up the bike back to where you first had it when it would fire up, make sure your battery is fully charged, adjust the valves again( should be a snap for you now ) so you know they're opening and closing right(timed), center the ign plate,make sure you got fuel going when you twist the grip. Do a compression test. The book will tell you the acceptable range ,no more than 10% difference in both cylinders.

The clymer is better than no book but you should get the factory Service manual, they are the best.The parts catalog is very helpful too.

I'm thinking your not getting enuf spark to light er up

Take your time,when you do get it,you'll feel great!!
Keep us posted.

[ironhorse]

going with lucifer on this some but only thinking a compression test is a good idea but it was firing before, only dieing later tells me that you probably have enough compression, may not be good compression but enough to fire, and the compression only increases as the eng gets some warmth, I am leaning towards a spark problem most likley coming from your elec.igniton. enough energy storage for a few bursts, then dies out could be electrical supply, or the electronic igniton itself, first make sure you have a good supply of power, use a battery pack/charger, as you start it with it hooked up and it stays running fine disconnect it and if it dies then look at your electrical circut, gen, batt, wiring. but with it remaining hooked up if it still has the same problem, then look towards the ignition, and wiring. just a couple of ways to go hope one of us throws the fix find your way, as the loss of ride time can sure get under the skin, best of luck.

[Lucifer]

Originally Posted by ironhorse

going with lucifer on this some but only thinking a compression test is a good idea but it was firing before, only dieing later tells me that you probably have enough compression, may not be good compression but enough to fire, and the compression only increases as the eng gets some warmth, I am leaning towards a spark problem most likley coming from your elec.igniton. enough energy storage for a few bursts, then dies out could be electrical supply, or the electronic igniton itself, first make sure you have a good supply of power, use a battery pack/charger, as you start it with it hooked up and it stays running fine disconnect it and if it dies then look at your electrical circut, gen, batt, wiring. but with it remaining hooked up if it still has the same problem, then look towards the ignition, and wiring. just a couple of ways to go hope one of us throws the fix find your way, as the loss of ride time can sure get under the skin, best of luck.

I agree ironhorse,I don't think its getting hot enuf spark.After setting rods so often tho I figured a compression test will tell if its set up right again ,the same as it was when it worked for a bit. Then go from there.If the coil checks out good, it should be between the battery and the coil. Good idea to try it with the charger/battery pack hooked up to see if its the battery or not.
Kinda workin backwards from the plugs to battery and skipped the plug wires
but I think its either the coil, sensor or module.

[Bassman]

Well, you all may be right. I took my coil to a local reputable Harley dealer and he checked it on 3 different meters, just to make sure. My coil is a paperweight. Dead, nada, capput. So you guys seem right. I was suspicious of a weak spark myself and after getting a new coil, am hoping that it will fire.
I have not tried a compression test yet, but when bringing #1 to TDC and looking in the spark plug hole, she was blowing out plenty of air in my face.

I am no electronics expert by far, so here is a stupid question.
1984 Ironhead Sportster. Dual fire coil or single fire coil? I mean, did it come stock with??? The guy at my dealership said he could order me another coil and it would be $56. On ebay I have seen 2 much higher output, brand new in the box coils going for less. 1 is a single fire and one is a dual fire. I would rather get something with more output so as to assure I am sparking good. But neglected to see if my bike comes with dual or single fire. According to some reading, it is dual, stock from the factory. But I want to make sure.
Anyone?
By the way, thanks for the help so far. Highly appreciated as I would like to get in at least SOME riding before snow hits.

[chucktx]

it is a dual fire.......both cylinders fire at the same time...

[Bassman]

Thanks Chucktx,
I am on my way over to ebay to do the buy it now thing on that dual fire coil before someone else gets it. Hopefully in a few days she'll fire.
Only rode once this summer, and that was my buddy's 77 sportster. I want MY baby on the road though. Thanks again buddy.

[whacker]

Hope you get your baby runnning.I have a 75 iron head..I converted over to the single fire ignition Crane cams HI-4 ignition...it works well,... only fires the cylinder on the compression stroke,next project is putting on the CV carb I got from Ken...getting rid of the S&S...My Baby should run like a dream then...

[Lucifer]

Originally Posted by Bassman

Well, you all may be right. I took my coil to a local reputable Harley dealer and he checked it on 3 different meters, just to make sure. My coil is a paperweight. Dead, nada, capput. So you guys seem right. I was suspicious of a weak spark myself and after getting a new coil, am hoping that it will fire.
I have not tried a compression test yet, but when bringing #1 to TDC and looking in the spark plug hole, she was blowing out plenty of air in my face.

I am no electronics expert by far, so here is a stupid question.
1984 Ironhead Sportster. Dual fire coil or single fire coil? I mean, did it come stock with??? The guy at my dealership said he could order me another coil and it would be $56. On ebay I have seen 2 much higher output, brand new in the box coils going for less. 1 is a single fire and one is a dual fire. I would rather get something with more output so as to assure I am sparking good. But neglected to see if my bike comes with dual or single fire. According to some reading, it is dual, stock from the factory. But I want to make sure.
Anyone?
By the way, thanks for the help so far. Highly appreciated as I would like to get in at least SOME riding before snow hits.

The only stupid question is the one that wasn't asked, you learn by asking questions, and the learnin never ends.
No need to really check the comp,ya did it with yer face, if you have a compression tester go ahead, just suggested it to make sure everything was set up OK. You can use yer thumb instead of yer nose tho .
Next message we wanna hear from ya is that you put the new coil on and it fired right up and is runnin great!!

[stixx]

As you say the learning never stops. A few years back a guy brought an ironhead into my shop with the same problem as bassmans at first thought condensor,tried new one, no change, another no change, set valves at least 4 times changed carb, same timing cover off checcked cam allignment all fine,was going by all customers saying they never touched anything before problem, had spark , gas, the plugs were new accells albeit not supplied by us,no reason to think bad, after scratching my head for two days in despair cross referanced accell numbers turned out the shop that he got the plugs from gave him the short reach plugs from an earlier shovel, wrong heat range, proper plugs, vavoom, ran sweet. Ironhead high dome pistons are very heat range dependant. Another lesson learned.

[Bassman]

Well,
Got the coil. 45,000 volt output. Should really fire this baby up now.
But.........
I have no idea. I excitedly hooked her up, popped a little starting fluid in to assure it would fire, and......
1 loud CLICK. solonoid kicking the starter.

So let's revue.
I got it in feb of 07. All it would do is fire, but then backfire through the front pipe. Rode it once a whole 30 feet. (but it started everytime and ran)

This year, my buddy adjusts the valves, and it would only crank, but never start, and I notice a barely there spark and get a new coil. (but it would at least crank)

Now, I put on the new coil, and the starter will not engage.
Tried last night and the battery (which is a new gel battery) went dead within a few tries. I put it on my trickle charger for about 15 hours. Just went down to try. Each time I hit the button, it only did the click of the solonoid. After a few tries, the click click click of the battery being too low and the solonoid not having the power to start the bike. Battery dead again.
It never even cranked once.

Sorry Lucifer. I really wanted your last post here to come true. Put on the coil and put some miles on her.
I am at a loss. And with the time of year, I may just throw the cover on her till next year, hopefully getting enough of an income tax return to take her to a shop. That would hurt though. They want 66 bucks an hour around here, and that $ would be sorely needed elsewhere.
I tried. I may try something again this weekend. If not, thanks for the help my friends. I'll be around.
Later.

[hotroadking]

Do you have a digital multi meter?

If not Harbor freight sells them cheap, get one when you can.

Now pull the battery and take it to an auto parts store, they can do a load test to see if the battery is good, it may not be able to hold a charge, if it can then you need to look elsewhere, you may actually have a wire that is grounded and draining the battery.

Check the battery cables be sure the ground is tight, and that it has a clean connection, the end on the frame/starter should havea star washer under it to provide penetration through any powder coating,

Starters go from time to time but it sounds like you have power issues.

Once you get the battery back if it's good, charge it up outside the bike, then after checking the cables, install in the bike, check the battery with your meter should be just under 13 volts 12.6ish

Now see if it cranks the starter.

You could have a bad solinoid, and those can be rebuilt, you can get kits from any indy shop and do it yourself.

Buy a service and parts manual from HD for the bike so over the winter you can learn about every part etc. Plus they have wire diagrams so you can trace them to find problems.

Lots of other tests and stuff you can do to trace down the electrical issue but it sounds like a bad ground and weak battery.

[Lucifer]

Sheit

Seems like there a dead short in there somewhere, killin a new battery that quick, Dang!!! Do what HRK is saying, check your grounds and the solenoid, there could be a short in the starter. You're gonna have to go thru every inch of the starting circuit.
Get the HD shop and parts book and a multimeter and be thorough checking the starter.
Good luck man, you'll get er