The Honda PCX / Forza / ADV150 / SH Forums

Hi,

New poster here. Sorry but this may be a long one…
I am in the East Midlands in the UK.

I have a 2014 PCX125. I bought it in June last year and has been working great. It is kept outside overnight.
Just after Xmas I went to my bike after it had been stood for a few days and it wouldn’t start. It was cranking, but just wouldn’t fire up. You could smell petrol. I got my dad do try and jump it from his car, but no luck.
I read about the spark plug needed changing after 6000 miles so have done that, it still won’t start.
I called the AA, they couldn’t get it started so took it to the local bike garage that are highly recommended. They stripped it down, checked the injector spray pattern, spark plug and both were fine, charged the battery and it started.
They then put the faring back on and I collected it. They assumed it was the battery.

The following (cold -1 deg C) morning, the same happened. So I went and got a new battery, assuming that it was just not holding the charge. The existing battery was a Yuasa YTZ8V. I put my number plate into the Halfords website and it returned a YTZ7S as the battery I need. The YTZ7S is physically smaller than the existing one. I fitted this and the same happened. Not starting, smell petrol, etc.

The AA took it back to the garage, where it stayed for a week. They charged the battery and it stated every time (it was kept in their garage overnight which was considerably warmer than the outside temp). We went to collect it, and as the garage were re-fitting the faring, they tried it again and it didn’t start. They have had it for another week, did nothing to it but charge the battery try and start it and it started every time with a charged battery.
Collected the bike last Tuesday, rode it for three days no problem (started like a dream, even in snow flurries)
I was away for the weekend, which was Arctic conditions came to it yesterday and it didn’t start!!!

Now here is where it goes a bit strange, I thought I’d take the battery out and charge it, but the old battery was connected (YTZ8V). So I took it out and put it on charge. I phoned the garage and they assumed the YTZ8V was the new one and had been using that all the time. They dropped off the YTZ7S battery to me and I charged both.
Tried both this morning and neither was able to get the bike started. Same issue, cranking and petrol smell.

What battery do I need? Is the YTZ7S man enough? Am I trying the old battery which is man enough, but not holding the charge?
Help! I am at my wits end. I am a full time student with a part time job so can’t afford much.

Thanks.

I am starting to think that the old YTZ8V is buggered and I need a new one, but Halfords sold me the wrong battery.

If the battery (old) was charged and the bike started, then it should start with the battery freshly charged. What garage? They should have tested the battery and advised if it was faulty or not. It could be a cold start sensor issue, alternator issue, but the garage do not seem to know the PCX bike!

ANY hard-starting 4T engine should have the valves (intakes, mostly) put to specs, first.

When you say it turns the engine, does it do it at the same speed as before, and for how long before it stops?
Do you just do short journeys.
I have a Yamaha 1100 and 2 years ago I had a similar problem. Firstly I charged it with an old optimate for a week and the bike would start after turning for about 5 seconds and full choke (cold weather), left overnight the battery was dead. I bought a new charger and the battery would be fully charged after 3 hours, but left overnight it would be flat. Changed battery, everything OK.

Batteries are rated in CCA, or Cold Cranking Amps. Ironically, the CCA outputted drastically drops with lower temperatures, especially with older batteries. How long will it try to start for?

A YTZ8V (the old battery) outputs 120CCA, and YTZ7S (the new battery) outputs 130CCA, so it's not a power problem. The latter does have a bit less capacity, but I can't see that majorly affecting starting ability, especially if it tries to start (and quickly) on the battery.

Both are AGM batteries too, which means they're not user-servicible. If you KNOW the new battery is good, you may have a power drain somewhere on your PCX that is sapping out power. Even leaving a USB adapter to charge a phone plugged in can be enough to drain the PCX's battery, especially in cold weather. Do you have any power-related accessories that may do that?

I am surprised it didn't start when it was jumped. That's another symptom that's throwing me off. Did it try to crank up at the same speed when jumped as it does without a jump?

maddiedog wrote: A YTZ8V (the old battery) outputs 120CCA, and YTZ7S (the new battery) outputs 130CCA, so it's not a power problem.

Yuasa YTZ7S 12V Capacity Ah (20-HR): 6.3 CCA @ -18C: 130 http://www.yuasa.de/ytz7s.html
Yuasa YTZ8V 12V Capacity Ah (20-HR): 7.4 CCA @ -18C: 130 http://www.yuasa.de/ytz8v.html

aguim wrote:ANY hard-starting 4T engine should have the valves (intakes, mostly) put to specs, first.

Once again aquim is correct.

How many miles since last valve lash inspection?

This is not a battery problem if it turns over and doesn't start.

OP start with the basics.

What is required for a bike to start? Air, Fuel, and Spark right?!

You're obviously getting the first 2 assuming you don't have something jammed in your muffler or intake tract. In addition, you mentioned you smell fuel so all that is left is a spark. You can easily test this by removing the spark plug or simply grabbing another and place it in the spark plug ignition coil boot. Hold the boot and point the tip of the plug that sparks near either the head or block.. (few millimeters) have some one else hit the electric start and watch the plug tip. If it doesn't spark then your problem is with an intermittently faulty coil pack / ignition coil.

If you do get a spark then report back. We'll figure this out for you!

Hi.

Thanks for your replies.
I have had a new Ytz8v arrive. I charged it for over 12 hours just fitted it and the same.

I will try the spark plug and report back. Thank you.

Hi.
Right I got my old spark plug and did what you suggested and the spark is intermittent. I'd say about 10-20% of the time.

On a 4 stroke, sparkplugs only fire briefly every fourth stroke if working properly.
I'm wondering if you have a bad stator (starter for the PCX), or faulty brake switch.

Ok thanks for that reply, if that's the case then that it should only spark 25% of the time what is the best guess as to what the problem might be?

Sorry, I'm stupid, it doesn't fire 25% of the time, as it doesn't constantly fire throughout the total duration of the 4th stroke.
So your 10%+ guesstimate is fair I guess. I edited my post when I realised my faff, but you already posted after me.

Umm, yeah. Like I said, maybe something little like the brake (or sidestand) switch, or perhaps something big like the stator?
You really need an auto-electrician to check it out. Not a regular workshop mechanic.

Noted thanks for that, I'll see about the auto-electrician option.

It's not the brake switch because it wouldn't turn over if it was broken. Same goes for sidestand switch, wouldn't turn over.

What about the valves? How many miles ago were they checked?

Have you done a compression check?

Right I got my old spark plug and did what you suggested and the spark is intermittent. I'd say about 10-20% of the time.

Are you having us on????

Sorry. . .just kidding. . .I know it's painful when you invest time and money into your ride and it fails to deliver. . .

Another poster mentioned that it all comes down to fuel, spark, and air.

You are probably getting air, possibly getting fuel, not so sure about the spark. . .or that it is as it should be.

So let's take air out of the picture. But before we do are there a ton of miles on this PCX? Is the air filter clean??? You said it was running OK before you let it sit for a few days though. . .and you didn't ride it through a downpour before you shut it down last right?

It's a good point about the valves. . .but if it was running OK and you didn't sense any problems on the last few rides I'm thinking it's not valves. That being said I'm not a certified mechanic.

Do you have another spark plug or a new one? Is it possible to try and start the machine and pull the spark plug to see if it's wet? You say you smell fuel. . .but where is it coming from. . .the exhaust? or air filter cover? or someplace else?

If the spark plug comes up dry after trying to start it and it doesn't back fire or cough and spit like it's trying to start then I'm thinking fuel pump? The Forza 300's had issues with fuel pump materials back in 2014 (I think) and there was a recall on them for defective pump covers. . .but I didn't hear/read anything about the PCX models having fuel pump problems. I guess the part involved was made from some kind of resin that deteriorated.

If the spark plug comes up soaking wet. . .and it's a new plug or plug that is absolutely not cracked and "like new" then it's an electrical problem. When the cylinder is fed air and gas in a timely manner and it doesn't fire it's most likely an electrical problem. Which takes us back to the coil pack perhaps? Not sure. . .no fuses shorted out right? Did you check fuses? This link will take you to a recent thread that shows you where the fuse box is http://www.hondapcx.org/viewtopic.php?f=19&t=7178

I've got a motorcycle right now that has a battery on it's last legs and when it's cold out and I can't get it to start on the first few chugs I have to either jump start it off my Jeep battery (which never fails) or I put it on a trickle charge for a while until it's ready and more "like new". Then it will start right up. It's got a carburetor and choke so I always use a fuel additive to make sure the fuel stays good.

Just a thought. . .it's a tough one to figure out indeed.

A few added thoughts:

It is not uncommon for side stand safety switches to fail. . .on any brand.

I did buy a brand new battery one time for a motorcycle and it failed on me in a week. I tried to save some money and it was a mistake. . .although it was supposed to fit my machine. I couldn't understand how a brand new battery would fail like that. Sometimes they can short out internally. . .

YUASA is my brand of choice. . .had good luck with them in the past and won't go with a cheaper brand ever again.

That being said your PCX still should have started with a jump start OK. . .it's just that the battery would go dead shortly after you parked it if it was defective.

The YTZ8V is for 2015 PCX 150's.
The YTZ7S is for 2013/2014 PCX's.

The common denominator it seems is time. . .you let it sit over Christmas for a while before you tried to use it again.

You said that the shop got it started, checked everything out, thought it was the battery, and when they put the fairing back on it wouldn't start. Time went by. . .time for the battery to go kaput.

You also noted that when you were able to ride it for a bit you let it sit for a cold weekend and when you went to use it again it failed to start. . .with either battery charged. So now you had temperature and more idle time as part of the picture. The fact that you said you charged both batteries and neither worked is baffling. And you hooked them up correctly right? And right away?

Even if you did have a drain on the system somewhere you may notice your headlight starting to run dimmer. . .or gradually the PCX would crank over more slowly trying to start it. . .or it just wouldn't seem right. . .

You haven't smelled anything like electrical insulation right? Sometimes wires can wear thin if they are pinched between a frame and panel (or something) and vibration causes them to eventually go metal to metal and they short out or cause slow drain. Also water can get into connections and short things out.

Sorry, grasping at straws here. Maybe someone else has a better idea. . .I'm at a loss.

Apparently according to Honda, it's the rear brake lever which you have to pull right back (which I was doing) caused by some seizing on the brakes!!!??!!

I'm not convinced as it was turning over, just not firing.

Have you tried the other brake lever to start? I switched to the right brake lever to start the engine with no problems.