Tuning Question

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Okay, so I don't have a trike, it's a Harley 2014 Ultra Limited.

Configuration:

103 Cu In Water Cooled Heads

Vance and Hines Power Duals

Vance and Hines High Flow Slip Ons

Harley Stage One Air Cleaner

Dyno'd with a Harley Race Tuner

Symptoms:

When the engine is cool (Even when air temp is like 65*) for the first mile or two it will cough and sputter if you go to 3rd gear or above. The rpm goes up like it is cold and will come down fairly quickly unless air temp is like 20*,then it seems to stay up awhile longer. Keep it in 1st or 2nd and keep the revs up, about like 2500 rpm, and it seems fine. After a mile or so, IE Engine warmed up, it runs very well. Lots of power and pretty good gas mileage. IE, 48.8 mpg at 65-70 mph. Haven't gone on the Highway yet.

The bike runs really well once it is warmed up, maybe a tad of popping on decel, but, not terrible. I'd hate to spend the money on a Power Vision and find the tune I have is good.

Any ideas what could be causing this? Oxygen Sensor? I'm kinda at a loss. Most of the things I've come up with, in my mind, would affect the running all the time. Tune is all I've come up with.
 
It sounds like a lean hiccup to me

Check you plug wires, they are known for rubbing under the tank

Have you scanned for any codes?
 
Sounds the fuel enricher isn't given enough fuel to the engine when cold....

Similar to a choke coming off too soon....Or not closed all the way...:Shrug:
 
First, I'll check for codes and check the spark plug wires.

New info:

Last night when leaving bible study, air temp 56*, it did the coughing really bad for like I said, a mile or so if I was in 3rd or above.

This morning when going to get my allergy shot, after sitting in the garage all night (low 35*), and air temp 37*, it did not do it at all.

I had the same idea about the spark plug wires, so even though I couldn't pull the tank in the parking lot of the clinic, I did check to see if the plug wires where snug at the plugs. The rear one did feel like maybe it did slide down a tad and maybe click (could be wishful thinking). On the way home, it was 47* and the bike ran great. I was at the clinic about 35 minutes, probably not enough for the engine to cool down.

I'm thinking maybe the rear plug wire was loose, this doesn't really explain why it quits when the engine gets warm. Or maybe it's lean in the cold start area, and affects the running when the air temp is like above 50*. We haven't had any weather above 65-70 yet so I can't speak to that area.

Although in retrospect, I took a ride last week for like 70 miles, stopped and ate (I like to read when I eat, so I was there about an hour). When I started the bike to come home, it ran great, no coughing. It did cough a tad for like a mile when home I left, air temp about 55*. Coming home air temp was like 68*.

Could its be lean at a certain air temp, like between 50-60? Or maybe an hour in air temps around 65* wasn't long enough fo the engine to cool down sufficiently to replicate the issue.

If it's tune related, I will get a power vision and tune it. I do like the info I can get from the power vision, but, I'd really like to not spend $$$ if it's not tune related.

So in my mind, I will do the fault code check and see what that reveals.
 
Sure the weather specialy in Co where the air is thin can pose a problem

Keep in mind a HD tune is still TOO lean

IMO, get with Kevin @ DK, it is the best money spent

Checking and clearing codes with the PV seems to me a lot faster U can fine tune your riding and change fuel + timing for any riding, + view it any time you want

# 5 is a temp sensor. I wonder if it could be acting up?

HD14FLHR018.gif
 
Faults

Did check for codes and did have a PO152. That relates to rear cylinder O2 sensor rich. I cleared it and will check it again frequently.

I'm wondering if the rear cylinder spark plug wire was loose, erratic spark would make the O2 sensor "see" richer exhaust, am I right? I'll keep an eye on it.
 
Did check for codes and did have a PO152. That relates to rear cylinder O2 sensor rich. I cleared it and will check it again frequently.

I'm wondering if the rear cylinder spark plug wire was loose, erratic spark would make the O2 sensor "see" richer exhaust, am I right? I'll keep an eye on it.

That could do it

Check the screw on cap on the spark plug, I have seen them loose and cause problems and throw a code
 
Couple of thoughts-

I would chase down a few things first, before concluding it's the tune.

1. Plug wires can be seated well and still be bad. Years ago we tested brand new HD brand plug wires and found around 50% of them to be out of spec, straight out of the box. (we tested over 100 of them)

So, just because they look good and are seated well, does not mean they are good. Use some dielectric grease on all 4 ends.

2. O2 sensors do go bad, not often, but they do fail. Sometimes when they're in the early stages of failing it only shows up when they're cold. (check the wire connections too)

3. If you have an intake or exhaust leak somewhere, it could easily be leaking when cold, and then sealing up when warm.

4. If this has not occurred over multiple tanks of gas, look at that too.

That's all I can think of right now...but if any of the above are in play, they would still be in play, even if you spent the $ on a PV. So best to eliminate them before thinking about changing the tune.

The HD TC tunes are running on the ragged edge of lean, so if there is anything even a little off, it will show.

Kevin
 
Okay, so went for a short ride.

The PO152 code came back and it's 70* here.

I'll check all the things Keven mentioned and see if I can't lock it down ... :D ... might wait on checking the plug wires till there's less gas in the tank.

Another thought, i was told when I bought the bike that it was "tuned for mid grade" and I shouldn't run the higher grades. Never heard of that, but, maybe I'll go back to hi test, it's what HD recommends ... so it couldn't hurt.
 
#2 on what Kevin says

You have an incomplete burn in rear cylinder

The O2 sensor may not set a Check engine light however the ECM knows

Narrow down the problem in that cylinder and you should be good to go

I would start with the wire, and just me but I would change the plug also

IMO once a problem with a hiccup like this I do not trust the plug any more

It does not take a lot to ruin an other wise normal looking plug JMO

1 more thing I have seen injector wires too tight in the harness cause a problem like this

It is a pain to track down
 
I think when it cools down, like in the morning, I'll check the O2 sensor connection and swap out the plug. If that doesn't nail it down, it's waiting for the tank level to go down and check the wires. I happen to have a set that I know are good.

I forgot how much fun it is to own a Harley ... LOL.
 
Plugs and Wires

So winter has returned here (not really, 50*, cloudy and rainy with wind), I just didn't feel up to braving it and working on the bike. (and no Paws, it's not because I'm getting old :p)

I did however go to the "Company Store" and pickup some Screaming Eagle Plugs and a set of Screaming Eagle 10mm Phat Plug Wires (so fitting my bike has Phat wires)

Plugs 19.95.jpg

Phat Wires 29.95.jpg

I'm guessing I'll replace this stuff and check the O2 sensor connections while I got it apart tomorrow. I did talk to the service manager (he came over to the parts counter) He said the PO152 code is almost always a spark plug wire. He said it's kind of rare to need the O2 sensor replaced, but, if it does, he gets just under $250 to replace both (he recommends they be done in pairs), parts and labor. The exhaust system needs to come off. If need be, I'll let them do it. Getting too "experienced" to spend that kind of time on the floor and besides, I don't have an O2 sensor removal tool (hush Paws).
 
You are going to like those wires

They ohm test good

I don't like the SE plugs Just my deal Did some ohm checks on em, did not like what I saw

Never had any luck with them

I hope this solves your problem

Remember to check that cap on the end of the plug It should be snug;)
 
You are going to like those wires

They ohm test good

I don't like the SE plugs Just my deal Did some ohm checks on em, did not like what I saw

Never had any luck with them

I hope this solves your problem

Remember to check that cap on the end of the plug It should be snug;)

Thanks for the good wishes ... I really wanted to go with Taylor wires, but they needed to be special ordered. I've used these in the past and liked them. Had the Taylors on my tri ... in blue ... LOL.
 
Taylor makes GOOD wires

Seems to me if you take off your seat, remove the 2 rear tank bolts raise it up and block it you can fish the front wire out, careful with the fuel line

The new wires are fatter, I dunno if they will fit back in the guides under the tank

Best of luck to you;)
 
Thanks for the good wishes ... I really wanted to go with Taylor wires, but they needed to be special ordered. I've used these in the past and liked them. Had the Taylors on my tri ... in blue ... LOL.

Taylor makes GOOD wires

Seems to me if you take off your seat, remove the 2 rear tank bolts raise it up and block it you can fish the front wire out, careful with the fuel line

The new wires are fatter, I dunno if they will fit back in the guides under the tank

Best of luck to you;)

We carry the Taylor wires for the Twin Cam Trike IN STOCK at all times...in black. Other colors need to be special ordered. Here's a LINK to them.

On those SE 10mm Phat Plug Wires...test them with an ohm meter before installing....our experience is that over 50% of them are out of HD Spec, straight out of the box....we package a lot of our Coil Relo's with the SE Phat Plug wires, so we've tested a lot of them. :)

Kevin
 
We carry the Taylor wires for the Twin Cam Trike IN STOCK at all times...in black. Other colors need to be special ordered. Here's a LINK to them.

On those SE 10mm Phat Plug Wires...test them with an ohm meter before installing....our experience is that over 50% of them are out of HD Spec, straight out of the box....we package a lot of our Coil Relo's with the SE Phat Plug wires, so we've tested a lot of them. :)

Kevin

Dang ... wonder if Harley will let me return these .... usually no on electrical.

What should I be looking for on resistance? O ohms?
 
Dang ... wonder if Harley will let me return these .... usually no on electrical.

What should I be looking for on resistance? O ohms?

If you haven't installed them yet they should take them back

I think I measured my last set out at 40-50 ohms ( 4k- 5k on the 1000 scale)

I am anal about testing wires and spark plugs

On another forum , myself and a friend did tests on most major plugs including SE and Splitfire plugs and the problems with HD Ion Sensing

You would be surprised at what we found;)
 
Dang ... wonder if Harley will let me return these .... usually no on electrical.

What should I be looking for on resistance? O ohms?

It varies, model to model. It can be found in the service manual. For the 2014 Tri-Glide it is-

Resistance Value (OHMS)

8688-23,178 for the front plug wire

4188-11,172 for the rear plug wire

The reason they are different is because they are different lengths.

If they are out of spec, (outside the range listed above) the ECM will receive false readings in connection with the ION sensing for knock detection...this may result in the ECM altering the timing when it does not need to, compromising performance...all because of plug wires being out of spec.

Kevin
 

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