88 Sporty Electrical Issue?

[ghbloom]

Hi All,

First post, was hoping to get some insight to an issue I believe to be with the ignition system. I'm the 3rd owner of an 1988 Sporty. I am by no means a mechanic but have been wrenching on this bike for the last 2 years with relative ease... until I ran into this issue. The bike seems to cut out after it warms up to about 150 to 160 degrees.

Gas is getting thru the carb, float is good, battery and charging systems have been tested.... From what I have gathered I am likely dealing with a electrical issue with the ignition system. Could the coil be done? Does the ignition timing module need replacing? It appears that a previous owner swapped out the ignition timing module (programmable CompuFire) and the reg/rec (Accel) when they converted to the 1200.

Here is a video I took of it cutting out around 2:56.

https://youtu.be/8slort181_0

Experienced advice would greatly be appreciated.

[humancertainty]

The last coil I lost was fine until it warmed up. If you have another one around, you ought to swap it over.

[dirtygrotonscoundrel]

^^. This. If you don't have a spare coil, look at your manual and it should tell you how to check the coil you have, by checking the resistance. In some cases, this won't show an issue if the break in current only happens after the wires get hot enough to expand. But a good place to start.

[RickG61]

I have an 88 1200 I bought new. Its on its 4th coil now. The last one I bought was an Accel unit. Doesn't have much time on it yet, so time will tell if it works better. As stated above, test the resistance values on yours. BUT, also stated above is correct. One of mine seemed fine, test wise, but worked for shit.

One of them failed coils was found when I made the mistake of touching it while the bike was running. LOL Lit my ass up, and not in todays "lit" terms. Check the condition of the body of the coil, especially around the wire towers. One of mine had cracked pretty badly and one had small hairline cracks starting there.

[farmall]

You can use a heat gun to warm your module and coil separately for testing, and heat guns are insanely nice to have for applying shrink tubing, heat shrink splices and heating all sorts of stuff. Cheap is fine.

If coil and wires appear to be original I'd replace them as preventive maintenance anyway.

[ghbloom]

Thanks everyone for your input. You guys are awesome!

The coil appears to be original, or at least an HD OEM replacement. Since I am not the og owner, I have been replacing/rebuilding most of the important components anyways.

Accel Power Pulse on the way. I will let you guys know how it goes. Thanks again.

[Dougtheinternetannoyance123]

All electrical problems are fuel related and all fuel problems are electrical.

I agree with testing the coil is first place I would look, Get a spare set of spark plugs and clamp to the heads (Nevr run a EI without grounding the plugs to the engine),,, when the engine starts cutting out, shut off and quickly switch the wires to the new plugs and see if its spark,

There is flow charts for diagnostics in most factory manuals,,, follow it.

But I have had several bikes and cars with a pinched wire or the wire was breaking down internally (Broken strands of copper) and while it looked okay, any kind of heat-vibration-or load would cause intermittent or fail. Dirty ignition switchs, bad kill switch on the bars, bad terminals. Ohm meter is your friend.

Once you eliminate or confirm electrical look elsewhere. Poor fuel flow, clogged filter, bad vent on gas cap (Open the fuel cap when it cuts out, You would be surprised how often its just a bad vent. Vapor looking ALSO manifests itself as heat related. Pull the fuel bowl and PROOF all the jets, and float needle with compressed air and carb cleaner.

But its common depending on Left brain-right brain carb-electrical people where they start with such a problem, Seen a lot of folks start turning knobs and screws on the carb when it was an electrical issue and vice versa.

Maybe its just God and Arthur Davidson telling you its time to renew your garage relationship with your tools and scooter. (Service me! Service me!) Some bikes are co-dependant and need frequent wrench time. Ride - wrench- repeat.

[ghbloom]

So I swapped the coil out. No love. In a ditch effort to get this issue fixed before my last good run before winter, I swapped out the ignition module (Compufire model#21835) and got it up over 200 degrees without failure. Initially this seems to be the fix.

[Dougtheinternetannoyance123]

Hope you pinned it down. It is helpful but not always possible to have known good spares for certain parts to swap out to test & eliminate problems like this. (Or borrow a buddies part temporarily )
For my daily riders I try to carry important spares (Clutch cable, plugs, tools, spare brain box, fuses/breakers, tape, safety wire) But generally ignitions for EI are so reliable you only need one when you dont have a spare as they run nearly forever.
If this DOES solve your problem then look at why it failed, Mounting? Vibration or chafing? Water or oil damage?
Some companies simply dont give a shit, but the engineering side of most places often likes to see damaged or failed parts to look at why and might be worth shipping to them to look at.
Some places have told me to Fuk off,, but I have had others send me free replacements and a thank you so worth a shot.

(Those badlands voltage stabilizers for lighting are POS,, I have yet to find one on a bike that was working. I suppose there are a lot out there that DO work as they sell a lot of them,, but I have yet to see one on a bike that worked)

[farmall]

Since the old coil wasn't the problem, I'd keep that for troubleshooting.

I developed a useful strategy for almost everything I work on, not just vehicles. I stay alert for cheap or free spare parts and deals on consumable supplies. Done over the years the money isn't noticeable but the convenience is fucking wondeful.

Pull the fuel bowl and PROOF all the jets, and float needle with compressed air and carb cleaner.

To be specific , REMOVE those parts for cleaning or if things are the least bit questionable snatch the carb then strip, dip and reassemble and drain your tank then pull the fuel valve to inspect it and dump all residual fuel. Harleys are so easy to do there's no reason to wonder if a carb is fucked up or if you have nasties in your fuel tank.

If your bike is a keeper there's little reason not to accumulate spare carbs, overhaul 'em, then swaddle 'em in cling wrap to prevent moisture or dirt daubers fucking with them.

Four coils since 1988 is reasonable. I'm on number five on my '88 FXR. There's always a spare on the self because coils are consumable as asswipe.

Have a spare ignition switch too. They usually go intermittent as they wear and can piss you off no end if you don't know to watch out.

[ghbloom]

Well, swapped out the ignition mod and rode the shit out of her this weekend with no issues. About 450 miles and did not have it cut out once. Definitely stocking up spare parts when I can. Thanks again for the insight and advice.