12 Ultra, 103 start issue.. sometimes

[76shuvlinoff]

2012 103 with Andrews 54s and S&S premium lifters. Smith Bros adjustables. Power Vision Auto Tune. Those parts have 25K miles on them. SE compensator has maybe 10K miles on it. Yes oiling tray is installed. Battery is one year old. Plugs are new. Bike only has 30K miles on it. Not ready to trade it in.

I've been trying to pay attention but I think this is still going to sound vague. It's probably more than one issue. Most of the following have been going on for several years.

1) About once a day and usually a cold start, I turn the ignition on, the fuel pump cycles, hit the button and she won't fire. Let the fuel pump cycle again and she starts. This does not happen every time.

2) Cold button she occasionally grunts but does not stall. Warm it usually pops right off. Really heat soaked at a gas stop on a hot day I can almost promise an embarrassing hot start kick back. Sounds like I'm dragging a trash can full of rocks down an alley.

 I am not sure these issues are related. Would sticking ACRs cause any of the 2nd problems? 12 103s have ACRs right?     I've only had the tank off this thing once to change the breather valves, never been deeper into the top. 

[jsachs1]

On the ACR issue, I get a number of heads, with factory ACR's in for port work, etc. I find that an average of close to half of them have plugged relief ports  . I use a .150" diameter hard steel rod with a point to unplug the relief ports. If you suspect this problem, it's a time consuming job to clear them out. Exhaust system and reliefs need to be removed.
John

[76shuvlinoff]

On the ACR issue, I get a number of heads, with factory ACR's in for port work, etc. I find that an average of close to half of them have plugged relief ports  . I use a .150" diameter hard steel rod with a point to unplug the relief ports. If you suspect this problem, it's a time consuming job to clear them out. Exhaust system and reliefs need to be removed.
John

 This worth looking into, I could even wait until this winter, but if it were the case wouldn't my problem(s) be constant?

[Ohio HD]

Mark, the 103 inch in 2012 should have ACR's. An easy way to see if they're opening is take a compression test. The PSI should be low, maybe 130 to 150 PSI.

After that I'd look at the spring stackup on the compensator. Use Joe Lyons post about the spring height. I've seen brand new compensators where the springs were too short of a stack height. They need one or two compensator shims.

[kd]

Mark, the 103 inch in 2012 should have ACR's. An easy way to see if they're opening is take a compression test. The PSI should be low, maybe 130 to 150 PSI.

After that I'd look at the spring stackup on the compensator. Use Joe Lyons post about the spring height. I've seen brand new compensators where the springs were too tall of a stack height. They need one or two compensator shims.

I had one of the new +14 compensators that needed 2 shims.  I used Joe's sticky and the MOCO Instruction sheet for info and when measured I found 1 shim to be marginal but tried it anyway.  The next time I had an opportunity I installed one more.  It needed it and cured the rattle and kickback.

[Ohio HD]

Mark, the 103 inch in 2012 should have ACR's. An easy way to see if they're opening is take a compression test. The PSI should be low, maybe 130 to 150 PSI.

After that I'd look at the spring stackup on the compensator. Use Joe Lyons post about the spring height. I've seen brand new compensators where the springs were too short of a stack height. They need one or two compensator shims.

I had one of the new +14 compensators that needed 2 shims.  I used Joe's sticky and the MOCO Instruction sheet for info and when measured I found 1 shim to be marginal but tried it anyway.  The next time I had an opportunity I installed one more.  It needed it and cured the rattle and kickback.

I also had an SE compensator that I used two shims with. I was replacing the springs when they sacked out. The new springs needed two shims to get them to the proper stack height of 0.286" - 0.326".


Link to old post.
https://harleytechtalk.com/htt/index.php/topic,68275.msg1169753.html#msg1169753

[jsachs1]

On the ACR issue, I get a number of heads, with factory ACR's in for port work, etc. I find that an average of close to half of them have plugged relief ports  . I use a .150" diameter hard steel rod with a point to unplug the relief ports. If you suspect this problem, it's a time consuming job to clear them out. Exhaust system and reliefs need to be removed.
John

 This worth looking into, I could even wait until this winter, but if it were the case wouldn't my problem(s) be constant?

Not necessarily. It CAN be inconsistent.
John

[flhtmojo]

I have a 2011 flhtk. Same problem. Tried plugs ,fresh battery,plug wires. Same thing.
Went after battery connections cleaned used dilectric grease no change.
Pulled battery, there are ground connections in front of the battery, left side, cleaned then and dielectric grease applied.
Next cleaned and greased ground connection under the starter.
 Lot of white corrosion on  A pain to get to.
 Need to remove chrome cover on starter.
11 mm wrench to get the nut off ground post.
So far the problem starting seems to be fixed.

[Hossamania]

I will also offer that I seem to have more start issues when I don't charge the battery on a regular basis, flhtmojo's experience mirrors mine in that regard, a less than perfect battery causes kickback for me at times.

[76shuvlinoff]

Thanks all. The bike has been sitting for a few days. This morning I cranked it cold. Motor spins but didn't fire. I let off the button, fuel pump cycled again and then it fired right up. 

 As far as the possible battery issue goes I will put in on the tender every night for a while to see if that's related to my hot kick back.

Mark, the 103 inch in 2012 should have ACR's. An easy way to ghsee if they're opening is take a compression test. The PSI should be low, maybe 130 to 150 PSI.

After that I'd look at the spring stackup on the compensator. Use Joe Lyons post about the spring height. I've seen brand new compensators where the springs were too short of a stack height. They need one or two compensator shims.

 When I installed the SE comp I used Joe's guidelines and it was within spec.  Could be it needs another look by now though. Next time I put the bike on the lift I will do a compression test.  Any special procedure for this? I've only used my tester on pre evo stuff and a 76 Chevy.  thanks!

[Ohio HD]

There are two ways to test compression in this case. One by just using the gauge, both plugs out, and throttle blade opened by hand, crank the motor by the bikes starter. This tests with the ACR's opening, the results should be a low reading if they are opening.

The other is both plugs out, throttle blade open, and I use a starter jump switch at the start and battery to crank the motor. That way the bikes ignition switch is off, ACR's are off, and the compression should be higher than the previous test as ACR's are closed.

[Hossamania]

Is there a fuse for the fuel pump that should be pulled to prevent that from pumping during the test?

[Ohio HD]

Is there a fuse for the fuel pump that should be pulled to prevent that from pumping during the test?

Pretty sure that would also shut down the ACR's. The test couldn't be performed.

[Hossamania]

Maybe just disconnect the fuel line?

[Ohio HD]

Maybe just disconnect the fuel line?

Why? HD Service manual says just crank it over when performing a compression check. Nothing about shutting any systems down.

[Ohio HD]

This is the instructions for a pre ACR bike. Just hook it up and run the test. The only reason they say in an ACR bike to remove the System Relay is to shut off the ACR operation. And I as stated above, I just use a starter jumper switch.

To test ACR operation all system need to be operational.

[Hossamania]

Maybe just disconnect the fuel line?

Why? HD Service manual says just crank it over when performing a compression check. Nothing about shutting any systems down.

Didn't know that, I figured that fuel squirting during a compression test wasn't ideal, but it must not matter, or doesn't spray during the test?
When I tested an '01 with MM EFI, it was recommended to disconnect the fuel line or pull the fuse, can't remember which, then start and burn off any fuel, which took a couple seconds of running. Then test.

[76shuvlinoff]

Thanks guys.

[76shuvlinoff]

 
I don't know why I fail to retain this. It's burned me a couple times now.

I will also offer that I seem to have more start issues when I don't charge the battery on a regular basis, flhtmojo's experience mirrors mine in that regard, a less than perfect battery causes kickback for me at times.

Found out the battery is 2 years old, not one. It's too early to claim a bad battery but I do a lot of short hops lately. I've cleaned connections and put it on a tender for the last 4 nights. The first night it took over 8 hours to bring the battery up to full. While leaving it on the tender every night none of the hot or cold starting issues have returned including hot start kick back.  I will check the voltage at the battery while running then stop using the tender for week or so, if the crap comes back I'll get another battery and get religious about using the tender.

[motorhogman]

My starting and charging system is all stock 22 years, 120,000 mi. I was experiencing "hot soak" and occasional kick back.  Usually after battery has been in service for 1 1/2 to 2 years.  Installed 2 GA cables. and haven't had a any sign of a hot soak or kick back. We have had some very hot days in SC and the system has been tested several times with a quick stop and restart  situations. Before I installed the 2 GA cables I could predict when the hot soak would happen. Stop at the ATM.. Stop for gas.. Etc,.   

[Scooterfish]

76, Do a starting load test on battery with volt meter. I think volts should stay above about 10 volts.

[Hossamania]

I don't know why I fail to retain this. It's burned me a couple times now.

I will also offer that I seem to have more start issues when I don't charge the battery on a regular basis, flhtmojo's experience mirrors mine in that regard, a less than perfect battery causes kickback for me at times.

Found out the battery is 2 years old, not one. It's too early to claim a bad battery but I do a lot of short hops lately. I've cleaned connections and put it on a tender for the last 4 nights. The first night it took over 8 hours to bring the battery up to full. While leaving it on the tender every night none of the hot or cold starting issues have returned including hot start kick back.  I will check the voltage at the battery while running then stop using the tender for week or so, if the crap comes back I'll get another battery and get religious about using the tender.

I failed to mention, 8 hours on a tender to bring it back up to full is a long time normally, that would indicate it had run down quite a bit, probably due to the short trips.
For peace of mind, I would do a running voltage test to rule out a bad regulator or stator.