Cold starting problem.

[Mr. Whippy]

The 2004 Multistrada has been showing an odd pattern in the last several months.  Sometimes it won't fire in the morning.  There's no real pattern to it.  Could be warm or cold out (but it seems like it's worse when cold).  The bike cranks like normal but just won't catch.

Sometimes cracking the throttle open will let it fire but then it idles rough for a while and I have to keep rpms up to keep it from dying again.  If it won't fire, sitting a day or so, it will spontaneously fire up fine (almost quicker than  normal tbh) and run fine for weeks at a time.

The carbon canister has been removed a long time ago. The tank is never pressurized.

My thought is partially plugged or worn out injectors.  It does seem to be better with Seaform in the tank but it happens so infrequent ly, I can't be sure if it's really helping or not.

I sort of have discounted coils because it gets better and stays better for long periods of time.  I upgraded the cables a couple years ago and honestly, it cranks completely normally.

Any thoughts?

Can I pull the injectors and crank the engine to look at spray pattern or is that a "bad idea"?

[bomber]

My experience says that looking at the injector pattern will reveal a problem only of they are really FUBARed . . . . like damn near plugged . . .

One of the reasons is, what is the baseline of a "good" injector pattern?

Like you, my money is on the injectors needing some love . . . . Depending on their cost (and the mileage on the scoot), replacement might be a good idea.

Lastly, and you already know this, a model specific forum will reveal metric furlongs per fortnight of data -- you are very likely not the first owner experiencing this issue.

[Slartibartfast]

I could be way off base here, but when were the valves checked last? My Rancher was exhibiting very similar symptoms and I found one of the valves to be tight. After adjusting to spec it went back to behaving like a Honda again.

[HipGnosis]

See if you have spark when it doesn't start - I have a pencil size tester that lights up when held next to a plug wire (that has spark running thru it).  Get something like that and keep it near the bike.
How many miles on the bike?  How many on the plugs?
You haven't convinced me it's NOT the coils.   Random gremlins are most often electrical.

[black hills]

simply things first.. Is it really cranking good? check the battery and the connections (My CBR starts hard when the battery is about gone, yet still seems to be cranking OK?).

[Mr. Whippy]

My experience says that looking at the injector pattern will reveal a problem only of they are really FUBARed . . . . like damn near plugged . . .

One of the reasons is, what is the baseline of a "good" injector pattern?

Like you, my money is on the injectors needing some love . . . . Depending on their cost (and the mileage on the scoot), replacement might be a good idea.

Lastly, and you already know this, a model specific forum will reveal metric furlongs per fortnight of data -- you are very likely not the first owner experiencing this issue.

Multistrada.net is a funny place.  I joined in 2003, but actually haven't had much helpful response to direct questions I've posted.  Searching came up with the possibility of the injector relay (corrosion) which I'll look at.  Generally, the mechanics knowledge is better here at ST.N

I could be way off base here, but when were the valves checked last? My Rancher was exhibiting very similar symptoms and I found one of the valves to be tight. After adjusting to spec it went back to behaving like a Honda again.

The valves/valve seats and guides were redone about 6K miles ago.  New hardened seats and guides are supposed to extend the period between valve checks.  The inconsistency of the problem makes me think electrical/fuel feed rather than mechanical (which shouldn't get better, just stay the same or get worse...)  Something to keep in mind...

See if you have spark when it doesn't start - I have a pencil size tester that lights up when held next to a plug wire (that has spark running thru it).  Get something like that and keep it near the bike.
How many miles on the bike?  How many on the plugs?
You haven't convinced me it's NOT the coils.   Random gremlins are most often electrical.

Good thought.  I think my timing light does this.  30K on the bike.  Plugs replaced 3K miles ago.

Coils/plug wires are my second suspect.

[Mr. Whippy]

simply things first.. Is it really cranking good? check the battery and the connections (My CBR starts hard when the battery is about gone, yet still seems to be cranking OK?).

The battery is a few years old, but seems to crank fine.  In fact, this morning, it started right up at 33F  Yesterday at 42F, It wouldn't fire at all.  Weird.

[Slartibartfast]

Do you notice this problem more when it's damp/humid?

[Mr. Whippy]

Do you notice this problem more when it's damp/humid?

Not especially.  It's parked inside but I do ride in fog/rain etc so moisture could be a part of it...

Would that favor coils or plug wires?

[Carbonero]

Many bikes have to balance the cranking with the spark generation. There might be a deficiency. The cranking will, of course, suck up every available amp and watt and volt and if there's questionable voltage going into your pulsar/cdi/coil/computer, then you could be experiencing weak spark.

When it happens, pay attention to see if it wants to "catch" as you let off the starter button. If so, you're on track for this being the case.

Run a voltage drop test along both circuits; starter and primary ignition. You may find you've simply got weak spark while cranking; this could be due to a number of connections needing attention, or even just a battery getting "iffy" under load, or even the starter drawing too much due to friction, worn brushes, bad armature, etc.

It's worth checking the valves, but I do agree; this feels more electrical than fuel or mechanical.

$.02

[Slartibartfast]

I was thinking more of a connection somewhere. Moisture can magnify a corrosion-induced short. Coils, if they are failing, will *usually* present as they heat up and the faulty wire separates as things expand, but not always. Old plug wires can get 'leaky' as the insulation breaks down and moisture will exacerbate that so I wouldn't discount them as a possible cause.

[HipGnosis]

Agree it could be a poor connection.
Does the bike crank but not fire with the kill switch off?  The side stand down?

[black hills]

next time it happens stop, put a charger on it and try again.

[Mr. Whippy]

Agree it could be a poor connection.
Does the bike crank but not fire with the kill switch off?  The side stand down?

Sidestand down or kill switch prevents the starter from cranking at all.  I have to see if it tries to catch at the end of cranking.

BTW, on the Multistrada, i don't have to push and hold the starter button.  Once "activated" it cranks on it's own for several seconds or until it fires up.
Posted on: December 20, 2012, 11:06:03 AM

next time it happens stop, put a charger on it and try again.

Great thought.

[Carbonero]

BTW, on the Multistrada, i don't have to push and hold the starter button.  Once "activated" it cranks on it's own for several seconds or until it fires up.

My Guzzi had that "feature", too. Not really a fan.

[mxvet57]

What about low fuel pressure. The pump could be starting to go. When it starts seizing it will work fine one time and next it won't turn fast enough make enough pressure.

[HipGnosis]

BTW, on the Multistrada, i don't have to push and hold the starter button.  Once "activated" it cranks on it's own for several seconds or until it fires up.

I've never heard of that.  But it will make testing spark easier!

[Andrew]

If the battery comes back OK, might consider checking the CTS & ATS (coolant temp & air temp)

but my bet is the battery

[Dan K]

Many bikes have to balance the cranking with the spark generation. There might be a deficiency. The cranking will, of course, suck up every available amp and watt and volt and if there's questionable voltage going into your pulsar/cdi/coil/computer, then you could be experiencing weak spark.

When it happens, pay attention to see if it wants to "catch" as you let off the starter button. If so, you're on track for this being the case.

Run a voltage drop test along both circuits; starter and primary ignition. You may find you've simply got weak spark while cranking; this could be due to a number of connections needing attention, or even just a battery getting "iffy" under load, or even the starter drawing too much due to friction, worn brushes, bad armature, etc.

It's worth checking the valves, but I do agree; this feels more electrical than fuel or mechanical.

$.02

If that was the problem, that wouldn't cause the rough running on idle once started, would it?

- Dan

[Baz]

Does the Multistrada have coils?

My old Bandit and even older Honda VF would not run around the freezing mark. The coils on both of those bikes were adversely affected by cold. If I took a hairdryer and warmed the coils up, the bikes would run like a dream.

So my advice would be to remove the tank, warm the coils for a few minutes, then install the tank and try starting the bike. You will know right away if that is the case.  

[Carbonero]

If that was the problem, that wouldn't cause the rough running on idle once started, would it?

- Dan

It could, if there's weak spark. Weak spark can look like a host of problems; fuel, air, mechanical, etc.

[Mr. Whippy]

I think I'm going to start by tracing down the electric, cleaning contacts and checking spark.  

About a month ago, I was able to pick up low mileage injectors from Metroduc, so if I can't solve with electricity, I'll swap out the injectors and see what happens.

[Carbonero]

Excellent. Keep us apprised.