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K1200GT Starting Problems

Nosbod

New member
My 2008 K1200GT is very difficult to start when it is hot. It barely turns over. I had it checked at Leo's South in Lakeville, MN yesterday and they said the battery and charging system are fine. When I parked in the garage, after a 45 min ride home, I tried a restart. Again, it would barely turn over (but it did start).

Any ideas?

Dave in Woodbury, MN
 
I know this may be a reach, but my 09 R1200GSA had a similar problem. Battery checked out fine, but wouldn't start when the engine was hot. Started fine cold. Turned out to be the starter. something about the brushes and adhesive or bushings. Don't remember exactly, but basically when hot there was extra drag in the starter itself and that made it crank slow. Local dealer mechanic diagnosed it immediately once they realized the battery was good. I saw a little on the internet about a run of bad starters. I have no idea if yours uses the same starter or not, but at least it is something to check.

A new starter (under warranty for me) solved the problem. One year later and no problem and I still have the OEM battery.
 
My 2008 K1200GT is very difficult to start when it is hot. It barely turns over. I had it checked at Leo's South in Lakeville, MN yesterday and they said the battery and charging system are fine. When I parked in the garage, after a 45 min ride home, I tried a restart. Again, it would barely turn over (but it did start).

Any ideas?

Dave in Woodbury, MN

Swap out the cable from the battery to the starter with a heavier one, but I'd check your connections first. It may be a loose connection to the starter or a loose earth connection.
 
BMW has a fix for this.
I also have an '08 GT, and had these hot-start issues. Their fix was an extra positive cable from battery to relay and relay to starter. No problems since.
My fix was covered under my extended warranty.
 
Is Leo's a BMW shop or...?

Did you ask to have the battery checked or did you ask why the bike is hard starting?

A good BMW dealer, if asked about hot start problems, should have done more than a battery check.

That said, dozens of things could be wrong. When you say "barely turn over", do you mean the motor turns very slowly or...? If the cranking speed is too low, I agree the starter could be the villain, but do the easy stuff first. Is the battery fully charged (maybe the alternator is tired and you're running on the battery a lot)? Clean the battery connections (disconnect the ground first and do the hot side first, and clean and reconnect the ground last) and make sure they're tight. Look for loose wiring from the battery to the starter. Do the easy stuff first - it's cheaper and more likely to fix the problem.
 
If his symptoms are the same as the dozens of others who have experienced this, it only happens when the engine is hot. But it's not quite that simple; for example, if you stall it it will usually start right away. Or it might start, but slowly. But if you stop for gas and the starter heat-soaks for a couple of minutes, it won't start. In my experience, if you let it sit for another few minutes, it starts fine. I would just walk away and have a smoke.
At first, the tech said he would have to experience it before the warranty company would cover it. I told him, "no problem, now that I know how it happens, I can reproduce it at will." He never made me prove it. Western covered it 100%.

This is how it was explained on another forum:
When the starter (any starter) is hot, it builds impedance. The battery cable may be insufficient to carry the necessary load under those conditions. I had the opportunity to pull my tank after the fix and see the obvious work done, which seems to be a second cable parallel to the first. This is the positive circuit from battery to relay, and the same from relay to starter.

I also agree that you should check all of the simple things first. One "so-so" connection could easily duplicate these symptoms. And even if a connection seems tight, you should loosen and re-tighten it if it's easy to get to. This sensitive (weak?) wiring is probably also why some guys have reported a "fix" after installing a stronger battery. But it doesn't seem to last. I have a Shorai battery that cranks like the living daylights compared to any other battery I've had, and I still had these hot start issues until the fix.
 
Er, impedance is (very loosely defined) opposition to current flow in an alternating current circuit. The key here is that a starter is a direct current device. Impedance doesn't apply here.

Possibly the explanation was an increase in [ohmic] resistance with an increase in heat? NTL, this is still a less than satisfactory answer. If it were correct, any motor (starter or otherwise) would pack it in as soon as things got hot. Practical experience suggests otherwise.

So... check the wiring for a bad connection. The increase in the starter windings' resistance with heating may be enough to cause problems if the voltage supplied is too low (i.e., bad connection = low voltage). If everything's clean, try putting a full charge on the battery, running the bike to heat it up, and see if the problem persists. It could be the battery is on its way out. Or it could be the starter really is in trouble (bad windings, worn brushes, or possibly bearings expanding from heating).
 
Impedance does not rely on AC vs. DC.
And this issue DOES exist in every electric motor or alternator. As they heat up, their impedance (or resistance if it makes you feel better) rises.
The design issue here is the gauge of the cable.
All of this, of course, is only relevant if this is the issue the OP is experiencing.
And if this wasn't the probable issue, BMW wouldn't be trying to fix it with extra wire.

HOWEVER, your advice to look for simpler issues is still sound. A bad connection can easily mimic a wire gauge issue.
 
Impedance does not rely on AC vs. DC.
Quite simply: nah. Start by looking here and head off to sources from IEEE et al.

And this issue DOES exist in every electric motor or alternator. As they heat up, their impedance (or resistance if it makes you feel better) rises.
The design issue here is the gauge of the cable.
All of this, of course, is only relevant if this is the issue the OP is experiencing.
And if this wasn't the probable issue, BMW wouldn't be trying to fix it with extra wire.[...]
In very crude terms, heating gets the metal's molecules dancing faster and faster, inhibiting electron transfer. The inhibition of electron transfer is a good working explanation for electrical resistance.

Note, however, that in an AC circuit, an increase in the AC frequency without a change in conductor temperature will raise the circuit's AC resistance (i.e., impedance) and the DC resistance will remain the same.

Other than getting the terminology right (and it does matter!), my point was and is "look for the obvious stuff first". Until the OP posts news on the bike, not more can be done here. :)
 
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