Unlucky K1100 owner

[bikesnbones]

My sorry story started a couple of weeks ago.
I was travelling down the motorway, at a fair old lick, when suddenly my 1993 K1100RS started misfiring.
I limped the short distance home, and found that it wasn't firing on cylinder 2.
Took the plug out, which was a mess.
So off it went to the garage, who called me in to give me the bad news just yesterday.
Both exhaust valves are damaged.
They look like someone's taken a chisel to them and broken the edges off them.
The piston crown has what can only be described as a dent in the top.
Finally, the bore has suffered some damage.
Not too bad, but the mechanic has advised that no matter what he does, he cannot guarantee it won't smoke afterwards.
So that's it.
At 43,000 miles, my engine, which was running perfectly before this happened, is now toast.
That's not the reason I'm here though.
I just thought you might be interested to know,
My question is, will the engine from a 1995 K1100LT go in OK ?
Would there be any issues to address.
I understand the later bikes had a different ecu / abs
Is that going to cause any problems.
It's just that I've been offered a nice one with warranted mileage and a 6 month guarantee.
Any help you can offer would be greatly appreciate, and I'm sorry my first post is a technical question.
 :dunno2:

[racinrich]

as a long time tech I would ask why it blew only one cylinder , external items that one would consider using from old motor may be the cause,intake boot, fuel injector, ecu . I would answer this question . careful look at the other cylinders may reveal clues. scored cylinder walls will cause consumption and other problems in driveability down the road . the motor will probably work but vin on case won't match frame so no trade in value with dealer.

[Scott_]

Yes. The basic engine is physically and mechanically the same.
The only real differences between the '93 and '95 is the ignition controls.
The '93 has an extra Ignition amplifier module that the '95 does not have.

As far as the number stampings on the engine, they don't match anything on the frame anyway, the frame # is your VIN # for the title.
They indicate the week/year the motor was mfgr'd and some other manufacturing reference code# of some kind that probably isn't public.

For a 20+ year old bike, not sure trade in $ vary much if it was/wasn't the original engine. You could argue the point either way as far as engine with more or less miles than the rest of the drive train.

[bikesnbones]

as a long time tech I would ask why it blew only one cylinder , external items that one would consider using from old motor may be the cause,intake boot, fuel injector, ecu . I would answer this question . careful look at the other cylinders may reveal clues. scored cylinder walls will cause consumption and other problems in driveability down the road . the motor will probably work but vin on case won't match frame so no trade in value with dealer.

Yes this is the issue.
I guess there is the possibility of a overly tight valve clearance, or a faulty injector.
Either way, it doesn't matter as it's not an economic repair so the engine is destined for the dustbin.
I'm not worried about trade in values, as I never planned to sell it.
The fact that I'm going to so much trouble over a bike that has a retail value about the same as the workshop costs, is an indicator of that.
I do however have the bike on ebay at the moment, but it's likely I will cancel the auction, as I have found an engine.

Yes. The basic engine is physically and mechanically the same.
The only real differences between the '93 and '95 is the ignition controls.
The '93 has an extra Ignition amplifier module that the '95 does not have.

This is the engine I'm likely to buy, which as you see has all ancillaries attached.



It's from a dealer, with a warranted 33,000 miles, is fully tested and comes with a 6 month warranty.
It is from an LT.
I just don't want to spend all this money, and find there is a compatibility issue.
This is new territory for me.
 :dunno

[Scott_]

What you have to switch over kind of depends on your bike build date.(not the model year or sale year). Generally 07/93 was the last month of production of the '93 model year bike anyway, so chances are you will have to make the following changes.

Up to 07/93, you should have an ignition amplifier module(was a carry over from the K1004V design). IF you have this module you will also have to change your water temperature sensor that is mounted behind the radiator on the short riser tube. BMW change the water temp sensor at the same time as they did away with the ign module.
You will also have to re-use your existing wiring harness as well.

IF you engine build is after 07/93(realistically a '94 model year, but I've seen stranger things) and you have no ignition amplifier, you should be able to bolt up the new engine as is with all wiring as connected.......

[bikesnbones]

What you have to switch over kind of depends on your bike build date.(not the model year or sale year). Generally 07/93 was the last month of production of the '93 model year bike anyway, so chances are you will have to make the following changes.

Up to 07/93, you should have an ignition amplifier module(was a carry over from the K1004V design). IF you have this module you will also have to change your water temperature sensor that is mounted behind the radiator on the short riser tube. BMW change the water temp sensor at the same time as they did away with the ign module.
You will also have to re-use your existing wiring harness as well.

IF you engine build is after 07/93(realistically a '94 model year, but I've seen stranger things) and you have no ignition amplifier, you should be able to bolt up the new engine as is with all wiring as connected.......

Thanks Scott.
My bike was built before 07/93.
It is definitely the older model.
Is has the older abs system, and I understand the ecu is different,
Up to 7/1993 - ABS1, Motronic MA2.1
From 7/1993 - ABS2, Motronic MA2.2
If I'm using the existing wiring harness, will there be a problem there ?
Do you know what the actual differences are ?

[Scott_]

Absolutely you will need to use your existing bike harness as the new one will not have connections for the ign amp, that your motronic 2.1 will use. The pin-out is different in the motronic plug output for the spark plug coils. The 2.1 uses pins 1/2 to the ign amplifier that then in turn goes to the coils. The 2.2 uses pins 19/20 and goes directly to the coils without the ign amp assy, and pin 1 is now used for the fuel pump relay.
So there really is no "making the new harness work" short of getting a 2.2 module to use with it.........

I can't say exactly what the differences are for the water temp sensor. All I can tell you is that the '93 uses a different part # for the physical sensor than the '95 and later bikes with motronic 2.2.
The wiring schematics indicate that both versions are only 2-wire(1 sensor in/out) as opposed to the older k75/k100 vintage water temp sensor that also used 2 wires but the probe had 2 sensors in it(each sensor was 1 wire to ground)

[bikesnbones]

Absolutely you will need to use your existing bike harness as the new one will not have connections for the ign amp, that your motronic 2.1 will use. The pin-out is different in the motronic plug output for the spark plug coils. The 2.1 uses pins 1/2 to the ign amplifier that then in turn goes to the coils. The 2.2 uses pins 19/20 and goes directly to the coils without the ign amp assy, and pin 1 is now used for the fuel pump relay.
So there really is no "making the new harness work" short of getting a 2.2 module to use with it.........

I can't say exactly what the differences are for the water temp sensor. All I can tell you is that the '93 uses a different part # for the physical sensor than the '95 and later bikes with motronic 2.2.
The wiring schematics indicate that both versions are only 2-wire(1 sensor in/out) as opposed to the older k75/k100 vintage water temp sensor that also used 2 wires but the probe had 2 sensors in it(each sensor was 1 wire to ground)

Wow
 :eek:
So bottom line Scott.
Without any possibility of recourse from me.
Do you think my wiring harness will be compatible with the 95 engine

[Scott_]

Absolutely you will need to use your existing bike harness as the new one will not have connections for the ign amp, that your motronic 2.1 will use. The pin-out is different in the motronic plug output for the spark plug coils. The 2.1 uses pins 1/2 to the ign amplifier that then in turn goes to the coils. The 2.2 uses pins 19/20 and goes directly to the coils without the ign amp assy, and pin 1 is now used for the fuel pump relay.
So there really is no "making the new harness work" short of getting a 2.2 module to use with it.........

I can't say exactly what the differences are for the water temp sensor. All I can tell you is that the '93 uses a different part # for the physical sensor than the '95 and later bikes with motronic 2.2.
The wiring schematics indicate that both versions are only 2-wire(1 sensor in/out) as opposed to the older k75/k100 vintage water temp sensor that also used 2 wires but the probe had 2 sensors in it(each sensor was 1 wire to ground)

Wow
 :eek:
So bottom line Scott.
Without any possibility of recourse from me.
Do you think my wiring harness will be compatible with the 95 engine

Yes.
like I mentioned, use your harness. change over 2 parts, and you are good to go.

[RobP]

external items that one would consider using from old motor may be the cause,intake boot, fuel injector, ecu . I would answer this question . careful look at the other cylinders may reveal clues.

What would cause this sudden catastrophic failure?   Too lean mixture from air entering a crack in the boot or a faulty fuel injector?

[bikesnbones]

What would cause this sudden catastrophic failure?   Too lean mixture from air entering a crack in the boot or a faulty fuel injector?

Could be any of those.
One thing I forgot to mention was that I noticed coolant residue over the plastic heat shield that sits under the left foot, and it was sprayed up the silencer as well.
Mechanic cannot find any clues as to where it came from.
I should add that I was riding it hard at the time, but within the perimeters of it's performance.

[johnny]

everytime i stop for fuel i put it on the sidestand... pop out the oil sightglass... adjust my valves through the sightglass hole... pop the sightglass back in... commence to motobricking...

j o

[drut]

"What would cause this sudden catastrophic failure?   Too lean mixture from air entering a crack in the boot or a faulty fuel injector?"

From what I have gleaned from original post "foreign body" in combustion chamber such as broken off spark plug electrode such as : http://www.northamericanmotoring.com/forums/stock-problems-issues/223111-broken-spark-plug-caused-8000-engine-damage.html
  is the most likely culprit.I have only seen spark plug failure result in this twice in over 40yrs working as a vehicle mechanic but remember the devastating results well.

[kris]

Ouch!! Shit happens, doesn't it? I wish you luck. These are always tough decisions to make. The pain will fade once your brick is up and running again.

[bikesnbones]

Ouch!! Shit happens, doesn't it? I wish you luck. These are always tough decisions to make. The pain will fade once your brick is up and running again.

I've decided to bail out.
I had a good offer for the bike as it is, which I have taken.
The guy who's bought it tells me he has 15 K1100/100's in various states of repair, and assorted parts including complete engines
 :yow
I'm really sad as I had become very attached to the old girl,
I probably will get another one at some stage.
Thanks to everyone, especially Scott, for the useful and constructive input.
I'll just leave you with a couple of pics of the old girl during happier times.
Very few bikes have ever bought me the happiness that this one did.
All the best.

[F14CRAZY]

with a bike that clean I would have swapped engines but that's just me...

[Mongrel]

with a bike that clean I would have swapped engines but that's just me...

Have to agree - that looks great.

[Elipten]

For sure, that bike is clean!  I would have kept it running with an engine swap.  The buyer is a smart cookie to grab it.

[kris]

She sure is purdy!!

[bikesnbones]

You guys know how to make a guy feel remorse.
OK you're right.
I'm keeping her.
The mechanic is bringing her home tonight, and I'll cover her up in the corner of the garage and take my time deciding the best way forward, which is to source a good engine, and I have one in the pipeline, once I can resolve a few possible compatibility concerns,

[bikesnbones]

Just thought I would post up a photo of the damage on cylinder two, exhaust valves.

[mjydrafter]

Just for morbid curiosity:  Do you know if the valve clearances were in spec?  If the valves were tight, would the heating of the valves cause them to get brittle and break like that?

I have no idea, but I'm guessing the pieces of the valves are what "ate" the cylinder and piston.

Interestingly, I think folks were saying in the valve check thread on this page, that the 4 valves very rarely need adjusting...  I could be miss-informed as I have a lowly 2 valve.

Sorry about your bike.

[bikesnbones]

Just for morbid curiosity:  Do you know if the valve clearances were in spec?  If the valves were tight, would the heating of the valves cause them to get brittle and break like that?

I don't know for sure, but you are right.
It is a very strong possibility that tight valve clearances may have been the cause
I bought the bike with absolutely no service history, quite recently.
I would normally have looked elsewhere, but the condtion of the bike alone, was indication enough to me that it had been loved and cherished.
The valve clearances were on my to do list, but I never seemed to find the time or motivation to do it, ( I did change the oil and filter though)
Whilst I cannot say for sure, it looks like there is at least a very strong possibility that I MAY have paid the price for my laziness.
Note how clean cylinder 2 with the damaged valves is.
It must have been running white hot in there,
 :oops:

[Scott_]

If the temps got that hot in the head to get it that clean, I suppose it could also have been possible that it could have cooked the head gasket and caused your water leak as well.
In my conversations with other riders/mechanics this last weekend, general consensus of the water leak suggested head gasket failure for your water leak.

[bikesnbones]

If the temps got that hot in the head to get it that clean, I suppose it could also have been possible that it could have cooked the head gasket and caused your water leak as well.
In my conversations with other riders/mechanics this last weekend, general consensus of the water leak suggested head gasket failure for your water leak.

The bike now has a new engine bolted in, but the start up has been delayed due to the condition of the fuel rail.
My mechanic won't re fit it, and when I saw it today, I could see why.
It looks OK from the outside, but inside it's badly corroded.
It's a distinct possibility that this was the source of my problems,
Even though each of the injectors do have their own filters, they're not much defence against this sort of corrosion.
I don't know if this a known problem, but I thought it worth the heads up.
Good news is that it's a very cheap part,