xb12s sometimes doesn't start

[Jurrien]

Hi,

I have an 2004 xb12s which is an awesome bike.



But, approximately one out of every four times I try to start the bike, it doesn't respond to the starter button.
All is normal, i turn on the ignition key: headlights are on, I hear the fuell pump for a few seconds, three lights come on onto the display, one goes out after a few seconds (the engine light), all normal. And then.. nothing when I push the starter button.
Also no sound or relay click at all. Absolute silence.

Then when I turn off the ignition key and switch it back on, most of the times it does start and after that all is normal.

It doesn't matter if it is a cold or warm start.

Sometimes it doesn't start a few times in a row. I get the impression it makes a different if I put the bike in gear and push it a bit front and back so that the crankshaft rotates a little. But I'm not completely sure this is the case as I have tested it only a few times and I am not sure it is a pattern.

Where to start the diagnosis?

[Niklos]

Where to start the diagnosis?

I think the easiest thing to check is the battery. Which one is it ? Is it old ? Fully charge ?

[Jurrien]

I don't know how old the battery is. I think it is just the regular one. It is fully charged and when the bike does start like normal (which it does most of the time) the engine cranks over with a normal speed and starts how it should.
So my guess is that the battery is not the problem, right?

[Niklos]

I don't know how old the battery is. I think it is just the regular one. It is fully charged and when the bike does start like normal (which it does most of the time) the engine cranks over with a normal speed and starts how it should.
So my guess is that the battery is not the problem, right?

What is the "regular one" ? Make sure it is a good battery for your bike. It must be more than 200cca, should be AGM not liquid as it does not stand streight. You'd better have the original one which is the HD part OEM 65948-00A B or C. This battery is AKA the DEKA ETX14.

[user_deleted]

SIR: your answer lies within one of these two threads...see the info i provided and read thoroughly paying particular attention to the starter button circuitry specs that i mentioned. and in addition check your clutch lever safety interlock switch if so equipped with simple OHM meter......your igntion fuse for corrosion on the blade tips and companion fuse box female connectors....your starter relay for same. this is where your problem lies.

https://www.buellxb.com/forum/showth...ry-issue/page2

https://www.buellxb.com/forum/showth...topped-working

[34nineteen]

<lunaticfringe drops mic and walks off stage>

[Jurrien]

Wow, a lot of info in those topics! Nice.
Also the 2008 Buell XB Models Electrical Diagnostics Manual 99493-08Y looks like it will be very usefull.

One question lunaticfringe. Why is the number one action to get the battery tested at a a shop?
Like I said the engine cranks over at normal speed. Doesn't that tell me already that the battery is OK or is it still possible it isn't OK enough?
I am not questioning knowledge of you guys, just want to know what is the motivation to perform certain actions.

[Cooter]

IF wiggling, pressing harder on the yellow switch doesn't allow it to start when it's acting up, the next logical thing to do it to hold the starter switch and wiggle the clutch switch (including the wires to it), and do the same with the starter solonoid, as well as the fuses and relay in the fuse box.

Good preventative maintenance would be to clean the battery connections (remove them and sand the terminals to do it properly) and the relays are interchangeable, so the act of removing and re-installing them and the fuses can clean the terminals in the fuse box if you have any corrosion issues there.

Let us know what you find out, and good luck!

[Jurrien]

Wow thanks for all the replies!

1-look at your original post. you described instances of what i deemed "compression bump" ions ago on here. it's where 1 piston is nearing TDC on compression stroke and the starter motor does NOT have sufficient power to push said piston past that point in its stroke to start the rotating motion required to start the engine. always a sign of either one or more loose/corroded battery cables...or a weak battery.

No, I am sure it was not a compression bump. Even with a compression bump you should hear some clicking noise from the engine. In this case I hear nothing at all from the bike. Not a single click.

2-i know you're in NL so don't know where you sourced your battery BUT if it is Chinese or Taiwan it is garbage. try and source either a Deka brand or Yuasa if possible. minimum 220 cranking amps. Deka is manufactured by East Penn Manufacturing right up the road from me. they were the OEM issued battery manufacturer for all Buells and Harley-Davidsons and continue to be. superior batteries for a multitude of reasons. Chinese/Taiwan junk have arbitrary CCA ratings on same. all meaningless...all highly inflated. source # is ETX-14. do NOT purchase an L model. they are AGM meaning "absorbent glass mat". the XB angled placement...heat...vibration doesn't bother them.

3-Buells are, simply put, hell on batteries. they are also notorious for electrical gremlins and maladies as they age. most are directly attributable to a battery and/or battery cable problem. that's why you check there first.

I checked, I have a Yuasa battery in the bike. Couldn't read any specifications though. I have no idea how old the battery is as it came with the bike.

I read this as the engine wasn't cranking at all (so not the "compression bump"/ weak battery issues).

and "Then when I turn off the ignition key and switch it back on, most of the times it does start and after that all is normal" also suggests it's not a weak/old/corroded battery.

Both of those well described situations (THANK YOU, Jurrien) sound like the starter solenoid is NOT getting the +12v signal it needs to activate the starter from a healthy battery. Even a corroded battery connection usually 'clicks' before it doesn't crank.

Yes, thank you. This is exactly what I meant.

This is what I am going to do, in this order:
- Check all ground contacts and make sure they are all ok. (I have already read that a lot of Buell problems are related to grounding issues and I have never looked at those connections at my bike)
- Have a look at all the mentioned contacts in the starter circuit, like described in this topics and the linked topics (switches, relays, fuses) as I also did not have a look at them myself.
These two actions will cost me no money and seem like a good check anyway. After that I will work through all said in the (linked) topics and the Buell XB Models Electrical Diagnostics Manual.
I'll keep this topic updated.

What I definitely learned from this topic: don't get the cheapest battery (like I normally always did with my others/previous bikes) but get a decent one. And that a healty battery is needed in a Buell.

[34nineteen]

No, I am sure it was not a compression bump. Even with a compression bump you should hear some clicking noise from the engine. In this case I hear nothing at all from the bike. Not a single click.


Not necessarily. The battery could have enough amperage to hold the solenoid closed, just not enough to get past the bump.


I checked, I have a Yuasa battery in the bike. Couldn't read any specifications though. I have no idea how old the battery is as it came with the bike.

All the more reason to get it checked out at a battery shop (not necessarily an auto parts store)