Hard Start

[gijimbo1313]

I am sure the answer will be TPS reset. Had my pipe gutted, left the exhaust valve it. Sounds great, little loss of power in low end but I can live with that. Seems to "miss/sputter" intermittently at low RPMs. Then, a few days ago, would take a few attempts before bike would start. Once started, idled fine. Still has the intermittent "miss/sputter". Still has stock ECU, was told that as long as I did not modify airbox, stock ECU can compensate and not run lean.

 

[FIDOSOL]

Run 10-20 minutes at around 3500RPM to relearn the ECM. It might fix it...

 

[GatorBuell]

Have you done the Breather rerout.

 

[gijimbo1313]

I have not done the breather mod. Also, seems to be worse when it is cold, more so than before the mod. I don't ride the bike hard and was told the race ecm only changes the fuel mapping for higher rpms.

For the relearn, are the 3500 rpms in neutral or on the road and do you have to start over if the rpms drop below 3500?

 

[GatorBuell]

The breather mod will help a lot. The ECM running in closed loop will not help a lean problem it just adjusts to the conditions your in ie. Humidity or lack of, altitude . If its lean the only way to change that is a Race ECM, a EFI controller like Dobeck or Remus power commander or use mapping software like ECMspy or your dealer can change your fuel maps. Vtwins have a hard time starting in the cold so thats not uncommon, if its real bad make sure you use the motor oil recommended for your starting temps.

For cold weather starts

H-D Multi-grade
SAE 10W40
HD 360
Below 40° F (4° C)
Excellent

H-D Multi-grade
SAE 20W50
HD 360
Above 40° F (4° C)
Good

H-D Regular Heavy
SAE 50
HD 360
Above 60° F (16° C)
Poor

H-D Extra Heavy
SAE 60
HD 360
Above 80° F (27° C)
Poor

 

[gijimbo1313]

Were in Florida, so it really does not get that cold. Want to stay away from the race ecm as I believe that will really only help at higher rpms. I have heard good things about TFI Techlussion and Remus so may go that route. I am afraid that if I try ECM spy, I would mess it up. What does the TPS reset actually accomplish? I am curious as to how changing a pipe or adding a module could change that.

 

[GatorBuell]

Im in Florida too, Central Florida. The TPS reset only readjusts the position of the throttle in relation to the rpm so the ECM knows how much fuel it needs to be putting into each cylinder as you twist. When you change a pipe or a high flow filter your adding more air to the equation changing your idle rpms. Your idle rpm and throttle position is your base from where your ECM makes all its calculations, if thats off everything after that will be off also. Your basically just synchronizing your throttle, idle and ecm so there all on the same page.

 

[LeFox]

I am sure the answer will be TPS reset. Had my pipe gutted, left the exhaust valve it. Sounds great, little loss of power in low end but I can live with that. Seems to "miss/sputter" intermittently at low RPMs. Then, a few days ago, would take a few attempts before bike would start. Once started, idled fine. Still has the intermittent "miss/sputter". Still has stock ECU, was told that as long as I did not modify airbox, stock ECU can compensate and not run lean.

- you need a reset before your ecm can compensate, unless you have an '08 en up.
- your ecm will still run lean, since it runs lean from factory, it will only get worse with a gutted pipe.

but...your problem could also be a battery/ignition thing.
if your battery is nearing its end, your ignition is weak and will give you a bad burn.

 

[gijimbo1313]

Are we talking dangerous lean as in damging valves, piston, and plugs? I have pulled the plugs and they appear light tan....not sure how much tan was there before the mod.

 

[LeFox]

i'm not saying your engine will fall apart tomorrow but it isn't thge healthy thing...

how healthy depends on how lean

 

[gijimbo1313]

I think I will put the Doebek on as it does not require a dyno to set up and I can richen it up a litle.

 

[LeFox]

ok...typing something really fast and then shutting it down isn't my thing

a reset would already do alot...you got to weigh performance against mileage.
better performance does not equal better mileage.

getting in between the 2 will get you the best of both worlds and your engine will do ok.
running lean will give you a good (almost too good) throttle response, but will not give you the best performance.
best performance will not give you the best mileage...etc...

 

[gijimbo1313]

I am not really concerned with high performance or good gas mileage. Just wanted the sound but then became concerned about it running to lean. I will try the TPS reset first and see what happens then maybe throw the Doebek on it. The Buell guy here states that he does not think an exhaust mod would cause it to run dangerously lean unless I also modded the intake side also. Since there are no mods on the intake, he thinks I am ok as far as lean goes....but who knows for sure?

What is the breather mod I hear about?

 

[XBear9S]

When I switched my stock exhaust for a Jardine I had the same issues. She was hard to start, especially on cold days and she kicked and popped when down-gearing especially below 2700rpm.

When I dropped a new map into her (off ecmspy) she became a whole new beast. The bottom end came back and the popping went pretty much bye bye. I then opened up the box and fine-tuned a couple cells in the map and she's a happy, healthy, sexy creature.

That said, right after the mod, she became very hard to start. I took her for a good hard ride that kept the rpms well above 35k for about 30 minutes and that seemed to straighten things out and get her back when I wanted her. She still takes longer to warm up than she used to but no more double starts. That ecm needs time to adjust.

I would have noted that I ran her without the ecm mod for over 10, almost 20k miles. The mod was her 50k b'day present, and she's happier than ever. Marriage made in heaven (hell?)...

Robtk! a.k.a. "Special K"

"Faster, faster, faster, until the thrill of speed overcomes the fear of death!"

---A Late Anonymous Bueller

 

[Stevenc150]

What is the breather mod I hear about?

I'm not sure, but here's one thread about the airbox delete. It's for getting the most performance from your intake. Some have simply drilled holes, or opened up they're stock inner airbox, but the delete gets the most performance gain....along with an exhaust and ECM upgrade or remap.
Airbox Delete

 

[gijimbo1313]

I think I found an older post on how to do the breather reroute. I will take it apart today before heading to the parts store to make sure I pick up everything I need on the first trip.

 

[GatorBuell]

Rerout link

 

[gijimbo1313]

Perfect....thanks

 

[gijimbo1313]

OK, did the breather reroute, and now it won't start at all. I believe the problem is unrelated however as it was already getting progressively harder to start, especially as it got colder outside and it was really cold today. Plugs were wet so it is way to rich. Will trailer to to the dealer, I believe my problem is TPS related

 

[GatorBuell]

Is the battery having trouble turning the motor over?