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Brian G. Reynolds
31-Jan-10, 10:15 AM
Hi all,

I was playing with my engine yesterday and was having a bit of a problem with it....

With the engine running I removed the N01 spark plug cap and the engine died....
I replaced the plug cap and started the engine again, removed No2 plug cap and it made no difference to the engine at all... kept running...
I then tried removing No3 plug cap and again no difference even with No's 2 and 3 plug caps removed, no difference...
Then when I removed No4 plug cap the engine died!

Now the engine will start but does back-fire a bit…..

Would I be right in assuming the coil(s) have died?

I notice one coil runs No's 1 and 4 cylinders, whilst the other coil runs cylinders 2 and 3.

Are the coils interconnected some way or can (should) I just replace one coil?

Thanks all,

B.

John Robertson
31-Jan-10, 10:39 AM
Brian,

I'm sure the BMW experts will be along shortly but it might be worth swapping the coils (and connections) to see if the problem IS actually the coil (it could be the wiring rather than the coil ).

Brian G. Reynolds
31-Jan-10, 10:46 AM
Good point that John.

I have not taken the coils off so am not sure if they are handed as they have a little sticker on them saying...
Zyl.1u.4 Kl.Nr.1 Blau
Zyl.2u.3 Kl.Nr.1 Rot

Which I assume says,
Cylinder's 1 and 4. Coil 1 Blue wires,
Cylinder's 2 and 3. Coil 2 Red wires

You see, 3 years in the RAF serving in Germany did pay off!!! (maybe...)

Thank you,

B.

Philip
31-Jan-10, 11:44 AM
Hi Brian, like John says swap over the coils but before that check the wiring and more importantly try a new set of plugs. Its backfiring because of unbunt fuel. K100 coils are not usually a problem area and are cheap on fleabay. Philip

P.S. for understanding German consider this EU directive:

The European Union commissioners have announced that agreement has been reached to adopt English as the preferred language for European communications, rather than German, which was the other possibility.

As part of the negotiations, the British government conceded that English spelling had some room for improvement and has accepted a five-year phased plan for what will be known as EuroEnglish (Euro for short).

In the first year, "s" will be used instead of the soft "c". Sertainly, sivil servants will resieve this news with joy.

Also, the hard "c" will be replaced with "k". Not only will this klear up konfusion, but typewriters kan have one less letter.

There will be growing publik enthusiasm in the sekond year, when the troublesome "ph" will be replaced by "f". This will make words like "fotograf" 20 per sent shorter.

In the third year, publik akseptanse of the new spelling kan be expekted to reach the stage where more komplikated changes are possible.

Governments will enkorage the removal of double letters, which have always ben a deterent to akurate speling. Also, al wil agre that the horible mes of silent "e"s in the languag is disgrasful, and they would go.

By the fourth year, peopl wil be reseptiv to steps such as replasing "th" by "z" and "w" by " v".

During ze fifz year, ze unesesary "o" kan be dropd from vords kontaining "ou", and similar changes vud of kors be aplid to ozer kombinations of leters.

Und efter ze fifz yer, ve vil al be speking German like zey vunted in ze forst place...

Bryan
31-Jan-10, 05:54 PM
Nice one Phil i zhink my German haz iprovan no end. Oh and i would agree with Phil that the plugs do fail. This i,m sure will be the fault as your engine has had a good thrashing. Before you go spending any cash just change the coils around and check the problem stays the same.Good to here your getting the monster ready for another wet summer.

Brian G. Reynolds
31-Jan-10, 06:23 PM
Nice one Phil! I will be passing that one on!

I have now taken the engine out to do an oil and filter change!
That will make access easier whilst it is out, I will build something to hold it all in place and bench run it!

The plugs are not that old but I do have a spare new set so I will be give that a try.

Yes you are right Bryan, oil change, filter change, NEW skirt!!... is there no end to my servicing this year?????

With the skirt completly removed it looks like a speed boat!

B.

smallw1449
31-Jan-10, 10:20 PM
Hi Brian,

If when you get the engine back in and you still have problems give me a call, I am quite and 'expert' (has been drip under pressure) with these engines and it will be easier to sort out problems over the phone

Keith

Vortex Services
07793807073

Brian G. Reynolds
1-Feb-10, 11:14 AM
Thank you Keith, dam decent of you Sir!

B.

Brian G. Reynolds
6-Feb-10, 08:21 PM
I have now started the engine on the floor out from the craft. I changed all the spark plugs and it ran like a pig, but not on cylinders 2 and 3 so I changed the coil I had delivered yesterday (Ebay special) and the engine runs sweet again!

So the question, or two....

Am I right in assuming the coil is indeed dead and if so should I just bin it of can it be fixed?

I have changed both coils but did I need to do this? are they handed in some way, they both look the same to me?

Thanks all,

B.

Ian Brooks
7-Feb-10, 08:35 AM
I have now started the engine on the floor out from the craft. I changed all the spark plugs and it ran like a pig, but not on cylinders 2 and 3 so I changed the coil I had delivered yesterday (Ebay special) and the engine runs sweet again!

So the question, or two....

Am I right in assuming the coil is indeed dead and if so should I just bin it of can it be fixed?

I have changed both coils but did I need to do this? are they handed in some way, they both look the same to me?

Thanks all,

B.

Probably sensible to invest in a whole spare set of electronics and put them in a sealed box in the craft "in case of sonic attack". I keep a spare coil in in mine.

Philip
7-Feb-10, 10:02 AM
I have now started the engine on the floor out from the craft. I changed all the spark plugs and it ran like a pig, but not on cylinders 2 and 3 so I changed the coil I had delivered yesterday (Ebay special) and the engine runs sweet again!

So the question, or two....

Am I right in assuming the coil is indeed dead and if so should I just bin it of can it be fixed?

I have changed both coils but did I need to do this? are they handed in some way, they both look the same to me?

Thanks all,

B.

A1, bin it
A2, AFAIK the coils on all K100;s are the same, part number 12131459890. Its just the labels are different, ZYL 1&4 label is part number 71212305187 and ZYL 2&3 label is part number 71212305188. I'm good on usless info this morning!!!

As Ian says get a spare set of 'tronics, fleabay is your friend. Philip

Brian G. Reynolds
9-Feb-10, 12:28 PM
Thanks Philip and Ian, I have been carrying a spare, fuel pump, starter motor, fuel filters, spark plugs, both electronics boxes and a starter relay, to name the items I can remember! They are in sealed boxes stored under the seats!

I am considering, for various reasons, removing the headers exhaust pipes from the engine so I can re-seal them, but the studs look very corroded, I am worried that trying this will end in misery! Has anyone tried this? I know the studs are buy-able but if they snap of close to the head.....

B.

Bryan
10-Feb-10, 09:16 PM
Oh yes and you right disaster followed quickly behind. I,ve had to redrill and tap all my manifold holes. No easy task but another job ticked off the list.

Brian G. Reynolds
11-Feb-10, 12:07 PM
Thanks Bryan, just as I suspected!

Needs a bit more thought this one....

B.

Brian G. Reynolds
14-Feb-10, 08:23 PM
Well I have just found the source of a loud noise, the ehaust header pipe serving no 3 cylinder is very loose where it is fitted into the cylinder head block.

I had a look to remove the nuts and have discovered there are no nuts holding the pipe in place, they have been WELDED into place!

So now I need to find a friendly engineer that can remove and fit new studs!

What a bodge.....

B.

trev
14-Feb-10, 10:19 PM
What a bodge
Well that’s one way to put it Brian only a desperate man or an idiot would weld the headers to the studs!:mad:

Bryan
15-Feb-10, 05:42 PM
I agree with Trev. Thats a bodge no one wants! Still you would be better off taking those studs out and re-tapping them to m8 and bolting back to the motor. I,ve done it with little problem and its not a major with the engine out.Good luck Bri.

Brian G. Reynolds
15-Feb-10, 09:46 PM
As you both say, I do not need that!

I am wondering if it would be money well spent if I took the engine to a service centre and had the engine re-conditioned/serviced.....

Not sure if the head needs to come off to replace the studs, if not then just get that done but if so then get it serviced?

Bryan, you say M8, is that the size of the existing studs as it sounds like you fitted larger studs?

Thanks Guys,

B.

trev
15-Feb-10, 10:56 PM
Is the welded pipe and stud part of the original bike setup Brian, if so that would tell me that the bike was on its last legs when the engine was salvaged, this sort of repair is usually only done to something of low value.If this is the case the engine may well benefit from a strip down and rebuild and this would also boost your confidence in its reliability in the future.

Trev

Bryan
16-Feb-10, 07:34 PM
Hey Bri its not that bad to do. Yes m8 is bigger but there is plenty of meat for the new threads to cut in. That Bmw of yours has been great and i,m sure a rebuild is a waste of time and money. It was a wise move to toss that crappy Peaugot in the skip. I havn,t yet seen a K100 go bang i hope the first is,nt yours!!!!

Brian G. Reynolds
16-Feb-10, 08:25 PM
Hi Trev and Bryan, I have to say that the engine has behaved excellently, I have no idea how the stud(‘s) got welded but the noise I could here (and everyone else) only reared its ugly head at the Hover Show I think.

I contacted a local dealer today, Rainbow Motorcycles” to see if they could perform a service but they did not want to touch it, saying they charge £75/hr and it would not be worth their time and my money to do so, I think I can understand their thinking as it is an old engine, but they did say these engines are bomb proof….

I tried to contact a local independent company today but they did not answer their phone.

I now have the engine in the back of my van to drop off to a local senior mechanic, John Judge, to have a gander to see what he recommends… I used to work in the next building to John and he is a keen motorcyclist and car mechanic and helps run a local Karting team as their mechanic, and he is a nice guy!

I could perform a cylinder pressure test on it but like I said, it did work very well so I will see what John thinks….

If I end up doing the stud work myself do I need to remove the cylinder head to re-tap the stud holes? I hope not!

I have suddenly acquired an awful lot of work to do…..

B.

smallw1449
16-Feb-10, 09:00 PM
Hi Bryan

Where abouts are you (in the country). I can do the studs for you, its the first job I do when I get a K100 or an R series in, they always strip the threads.

Let me know if I can help

Keith

Brian G. Reynolds
16-Feb-10, 09:08 PM
Hi Keith, very kind of you again! top banana!

I am in Sheffield, actually Beighton which is just the other side of Rother Valley. The craft is stored in a barn about 1/2 a mile before the Rother Valley entrance!

I will see what happens tomorrow and give you a call if that is okay with you.

Be good,

Brian.