www.boxertrix.com

What with a new bike on the way, something has to go so the 1250 Bandit will be part ex’ed.

After shovelling the winter crap of it last week, figured it would be best to leave in Somerset so it’s as described when it’s handed over.

So, my London commuter has been the K13, starting from last week, but it’s not happy about it and has been in right strop.

- The mirrors do not seem to fit in the same gaps as the Bandit did
- Flat tyre (in all my years of motorcycling, that is honestly only the second flat I’ve ever had)
- Headlight bulb went
- Ignition barrel has become really stiff
- Nearly got knocked off when a car clipped me as I filtered in front (ok, maybe not the bikes fault but the way its going, I’m leaving on the list)
- Today, I stalled it and the thing wouldn’t re start, like it’s got a flat battery! Had to push the sodding thing the last 100 yrds to park it.
All in a week!

Beginning to feel like Basil Fawlty every time I go near it - ‘Right, I’ve warned you about this before….’

https://www.youtube.com/watch?v=78b67l_yxUc

Oh dear, sounds like a rocky start to your new relationship. Things will hopefully improve withthe spring weather.

These new fangled machines ain't wot there cracked up to be Dave, your best off sticking to a boxer

You may be right Phil!

Still, it redeemed itself a little tonight, started fine.

In fact it did the same thing to Gin last year on the way to the Welsh weekend. Stalled and then its like a flat battery. RAC bloke called it fuel lock, the injectors still pump fuel intro the engine after its stalled and hydraulic locks the motor. So he said anyway. Vapour lock?

Topcat wrote:You may be right Phil!

Still, it redeemed itself a little tonight, started fine.

In fact it did the same thing to Gin last year on the way to the Welsh weekend. Stalled and then its like a flat battery. RAC bloke called it fuel lock, the injectors still pump fuel intro the engine after its stalled and hydraulic locks the motor. So he said anyway. Vapour lock?

Sounds very reasonable/feasible.

I have a bike that does that if the petrol tap ain't used correctly.

The tap is tucked up under so you can hardly see it. I bartered the seller down quite a bit because he thought battery was duff. He bought a new un. But when I turned up to look, his smile turned upside down when it wouldn't start. I genuinely took it away expecting a new rectifier or some such hocus pocus. Turned out he'd been using the tap wrong. I'm not convinced it was causing 100% hydraulic lock, but the starter torque wouldn't touch it. I reckon it had enough fluid in there to alter the compression ratio sufficient enough.

Thanks for that, interesting stuff.

I must admit I wasn't sure when he told me but it makes sense.

Similar thing happened with a Tiger 955i. Stalled it in traffic on the M25 and it wouldn't start, had to push the bike across three lanes to get to the hard shoulder

Very hot day and the RAC chap (I know most of 'em all by name now ) said the pressure in the tank increases and stops the injectors working, just open the cap and re start. Wish they had said that on the phone, Friday afternoon on the M25 hard shoulder at the M3 junction isn't the nicest place to stand for an hour

Topcat wrote:
......Very hot day and the RAC chap (I know most of 'em all by name now ) said the pressure in the tank increases and stops the injectors working, just open the cap and re start. Wish they had said that on the phone, Friday afternoon on the M25 hard shoulder at the M3 junction isn't the nicest place to stand for an hour

I'm no expert and hopefully some nice person will shed more light, but that one sounds slightly dodgy?

Isn't the following true?

The injectors are pressure fed by a pump, at several bar pressure anyway. The pump is fed by gravity from (or in) the tank. The tank has a breather pipe to vent to atmosphere. The injectors are kept at a certain pressure (from a "rail") by virtue of a regulating valve. Too LITTLE pressure would screw the injection system up. Not sure about very modern stuff, but early stuff relies entirely on the pressure being kept known (not exactly constant as the regulator is linked to inlet depression I think?) and the period of injector opening is altered to suit the load requirement. Summat like that anyways.

But I have no hard experience of the remedy to be sure.

Cheers

Good point, the injector rail must of course be under pressure but are you sure that the tank is vented to atmosphere?

Wouldn't that lead to evaporation of fuel, plus I'm sure I've opened fuel caps on several bikes too a little hiss, as if under pressure. Perhaps its the tank / fuel pump link that has the problem? The caps have an O ring seal I think?

Someone who knows what they are talking about (I sure don't) please help

Topcat wrote:
Someone who knows what they are talking about (I sure don't) please help

I got nothin'

Topcat wrote:
......are you sure that the tank is vented to atmosphere?

Wouldn't that lead to evaporation of fuel, plus I'm sure I've opened fuel caps on several bikes too a little hiss, as if under pressure. Perhaps its the tank / fuel pump link that has the problem? The caps have an O ring seal I think.....h

Good points. No, I'm not sure. Like you say, it doesn't make sense to be directly vented for the reasons you give. But air must surely be allowed in somehow. Might be a very very lightly sprung one way valve.

Shows how much notice I've been taking when I fill up. Hee Hee.

I'll get on the case forthwith.

Cheers

Corvus wrote:

Topcat wrote:
......are you sure that the tank is vented to atmosphere?

Wouldn't that lead to evaporation of fuel, plus I'm sure I've opened fuel caps on several bikes too a little hiss, as if under pressure. Perhaps its the tank / fuel pump link that has the problem? The caps have an O ring seal I think.....h

Good points. No, I'm not sure. Like you say, it doesn't make sense to be directly vented for the reasons you give. But air must surely be allowed in somehow. Might be a very very lightly sprung one way valve.

Shows how much notice I've been taking when I fill up. Hee Hee.

I'll get on the case forthwith.

Cheers

Quick breeze through john robinson's fuel systems book and only a cursory mention on tanks. But they are vented. Either direct to atmosphere or via airbox. When I think about it, older bikes had a little hole in the cap, or sometimes vented to under the rim of the cap. Off road stuff used to vent via a tube poked into the steering nut.

Rest of the stuff I said also checks out.

Fair enough, I stand corrected

As a mate once said 'I'm married with kid's, I'm used to being wrong'

Topcat wrote:Fair enough, I stand corrected

As a mate once said 'I'm married with kid's, I'm used to being wrong'

You n me both! (Mine are 31 and 27).

I looked to learn, not to prove anyone wrong. Hope I didn't cause offence. None intended.

I don't know how the problem of evaporation is overcome? And the trick with opening the cap doesn't seem to make sense, but probably I'm just not fully understanding something?

Interesting little discussion, either way.

Cheers.

Corvus wrote:

Topcat wrote:Fair enough, I stand corrected

As a mate once said 'I'm married with kid's, I'm used to being wrong'

I looked to learn, not to prove anyone wrong. Hope I didn't cause offence. None intended.



Cheers.

Absolutely none taken

The hot starting issue with K12/13 models is a known issue, caused by a substandard spec starter loom.

When the engine gets hot the electricity doesn't flow as well down the starter cables and give all the symptoms of a flat battery. As soon as it cools it starts as if there's nowt wrong.

I know cos it's one of the Big Book of Fixed Things that my KGT has had done to it. BMW will replace the loom FOC on request but never did a recall I think.

My mate had his K13R done for the same hassles too.