Hi there. Stay by the 7, works better than the 8, even around here.
Best regards 
JAp

japuentes wrote:Stay by the 7, works better than the 8, even around here.

............even in Norway also..........

oliveri

the r in in the designation indicates that the plugs will have an inbuilt resistor ....for us folks this means a lower ignition pulse ,,, given that you have standard leads ...the r suffixes are designed for copper cables without resistances incorporated

heres the drum

measure your leads from ignition coil connection  to sparkplug top connector with a multi meter  set to 20.000 ohms ( you will need to find some straight solid copper wire or even a paper clip to extend the multimeter probe to get deep enough into the plug top , because of the shroud around the length of the connection to the spark plug lead )

you will see something like 2000  to 5000 ohms (differs per length of cable ) this will indicate that there is already some resistance in the cable length )

do this regardless , because it will confirm or point to a fault in the ignition system

many have found that the plug tops are really corroded from the fitting of plugs without the ferule ...and the spark attempting to jump the gap between  the lead connector and the plug .....the plug tops usually have a 3 mm threaded section  with a 6mm bobbin on top ...many plugs don't come with the ferule fitted ex factory nowadays  (as different to some years ago )   check your plugs for this ferrule also ...it could explain a lot in the future  ....and if not found ....try to get some ...you will need them for any of the ngk plugs

iridium are a waste of money and not correctly designed for the nature of the motor

platinum could be an advantage if you consider long term lasting of the plug ....but you can buy lots of plugs for the difference in price ...change normal plugs every 20,000 in any case ...platinum = 40,000 to 50,000 k

hope this helps

Definately, definately check the connector inside the plug cap. If they're green, poke them with a screwdriver and see what remains. I had an intermittant misfire on LFB and traced it to all four plug caps having completely corroded away. Never seen anything like it in forty years of riding/maintaining.

charlie99 wrote:the r in in the designation indicates that the plugs will have an inbuilt resistor ....for us folks this means a lower ignition pulse ,,, given that you have standard leads ...the r suffixes are designed for copper cables without resistances incorporated

I'm not totally understanding the resistance in the DR7EA plugs.
Is this spark plug suitable for an '89 K ? NKG site only refers to '90 onwards.
I just put a set of these in my bike yesterday because I could get nothing else locally and they needed replacing badly.

Cheers

Kaptain Holister wrote: NKG site only refers to '90 onwards.
I just put a set of these in my bike yesterday because I could get nothing else locally and they needed replacing badly.

Resistor plugs is used on the 4V models which have Motronic and other coils.
I don't think that the output transistors in your ignition ECU appreciate the
increased resistance.

in addition inge ...the primary and output of the 4 valve models  are different to the 2 valve versions  and perhaps the ignition leads ??

what I can say is for the 2 valve versions at least

so if you have a 2 valve version captain ...you might notice some difference when and if you change ......but all the same applies ...measure the leads first ???!!!

charlie99 wrote:in addition inge ...the primary and output of the 4 valve models  are different to the 2 valve versions  and perhaps the ignition leads ??

Ignition leads have the same resistance both 2V and 4V, but coil connectors is different.

good advice and reference as always inge ...thanks


I do recall that the primary of 4v models is a lot lower  by a big factor  

it might go to explain some of the differences ..I recall that many manufacturers  reduced (quite markedly ) the primary resistances  ( with the advent of better switching devices on the ignition ) In fact many installed a ignition amplifier ...for want of a better description ... to off load the new higher currents of the new and updated coils  from the ignition control unit

charlie99 wrote: In fact many installed a ignition amplifier ...for want of a better description ... to off load the new higher currents of the new and updated coils  from the ignition control unit

I think this is just the output transistors which is moved outside the box for
better cooling (using the battery holder as a heat sink).

On the second generation Motronic is redesigned, much smaller unit which
generates a lot less heat....and the "amplifier" is gone.

Local BMW dealer who I bought them from told me they would be suitable. So this is not the case?

I'll measure the impedance on the leads in the morning.

Thanks

Kaptain Holister wrote:Local BMW dealer who I bought them from told me they would be suitable.

Any other BMW dealer in the neighbourhood?

Inge K. wrote:

Kaptain Holister wrote:Local BMW dealer who I bought them from told me they would be suitable.

Any other BMW dealer in the neighbourhood?

About an hours ride.
I guess I just need to know if the DR7EA plugs will cause any problems in the short term.
Thanks

92 K100LT 2 valve and 84 K100RT also 2 valve. The only plugs in them have been NGK D8EA. Mild climate here, max generally 25C in summer and never a problem. Also they are very cheap to buy and readily available. I have never bothered to try any others. Most of the others seem to be special order here. Change them once a year. They don't come with the bobbins though. I do a fair amount of motorway runs at 5000rpm and they always come out the right colour when I bother to look at them. . . .

You're not the first one doing this mistake, I would guess it shouldn't be any problem
in the short term.
But it would be better to use the resistance your ignition system is designed for.

The only difference between D8EA and D7EA is that the D7EA will be a slightly hotter plug. I am on original coils and ignition system/leads so you should be fine. Given that the D7EA is recommended over the D8EA you should not have a problem. If you are a bit concerned just take a look at them after a decent run and check the colour. Two local BMW specialists here fit the D8EA to Ks when servicing them.

Just to clarify, I am not referring to DR8EA, but to D8EA plugs without the R!.

I would heed Inge's advice too. When you can, get a D7EA or D8EA set and fit them.

My reply was meant for the kapitän.

Inge

Sorry I wasn't trying to cross your posts but they got crossed. Of course yours was correct.

Its funny though that in some places they go with D7EA and in others D8EA and no problems. We can ride all year and we get no problems even in winter and even then no problems.

I would probably have about 10,000km on the K between now and April.

Thanks, you guys are are full of great info.

If I require to get a set of new leads at some point ( seen the NGK's for sale). Do they have resistors built in? If not, should I use an 'R' type plug once the leads have changed or will they cause issues with the coils.
Or simply 2V K = no 'R' plugs ?

Kaptain Holister wrote:Local BMW dealer who I bought them from told me they would be suitable. So this is not the case?

I'll measure the impedance on the leads in the morning.

Thanks

Just further proof of what I keep saying about dealers.
They probably would be OK in the short term and considering that the ambient temperature is fairly good here this time of year.

When dealing with ignition coils the source and load need to be the same impedance as in the secondary winding in the coil. It is 14000 ohms then the load I.E. the leads and plug need to be ideally 14000 ohms that way maximum power is transfered to the load so you get the best spark. So puting  a resistor plug, 5000 ohms in the circuit causes a miss match and as a result of that heat is generated within the coil due to power reflections this in turn effects the primary winding and it also gets those reflections transferred to it and then in turn to the output switching transistors which also get a heat build up and the result is fffooff and the transistor is returned to whence it came (beach sand) and the bike stops.

Inge K. wrote:You're not the first one doing this mistake, I would guess it shouldn't be any problem
in the short term.
But it would be better to use the resistance your ignition system is designed for.

Thanks Inge
I can't find any D7EAs locally but I can get D8EA.
My plugs have always been very clean when they come out so I'm thinking D7EA is the correct rating.

However, do you think going cooler by#1 will make much difference?

50% of my riding time is spent on the highway sitting on around 4½-6k. My understanding is that SP temp ratings relate to the performance rating of the machine and how it is used eg higher speeds for longer periods may need a cooler plug. And a little to do with environmental conditions only when temps become extreme.

Cheers

please correct me anyone , I run 7's in my 89' LT , with the resistor, DR7EA,previous knowledge suggested that these were due to radio being fitted.
PO had D7EA with no resistor , I had no problems during the 3 years of use.
Kapt'n , I have found Repco , cheaper and easier to access these plugs , even if you have to wait a couple of days for stock to arrive in.

I just reread the thread and see that 7 is prefered. Thanks
I'll have to order them in.

Will be returning the DR7EAs to the dealer tomorrow. Its only $16 but its the principle. This is the same guy that wanted to charge me $64 for an oil filter and $145 for a clutch cable saying it was the only one left in Australia (wtf there was certainly no shortage from other suppliers) On Friday when I asked if he could swap 3 shims he said I could buy a set (all the same size) and that I really should just replace all 8.

I am not even going to bother going into his dealership anymore.

groverK wrote:Kapt'n , I have found Repco , cheaper and easier to access these plugs , even if you have to wait a couple of days for stock to arrive in.

Thanks Ed
I called into Repco but their normal stock was depleted. So I'll head back tomorrow and get them to order a set in for me.
Cheers mate

groverK wrote:please correct me anyone , I run 7's in my 89' LT , with the resistor, DR7EA,previous knowledge suggested that these were due to radio being fitted.
PO had D7EA with no resistor , I had no problems during the 3 years of use.
Kapt'n , I have found Repco , cheaper and easier to access these plugs , even if you have to wait a couple of days for stock to arrive in.

I seriously doubt that BMW recommend that DR7EA be fitted when a radio is fitted and if you do fit them then the system needs to be balanced as in source to load as I talk about above.

Grover and Kapitän.....all this about R or not is of course based on that you have
the genuine HT wires which have resistors integrated.

If the HT wires have been changed out things suddenly looks a bit different.

RicK G wrote:

groverK wrote:please correct me anyone , I run 7's in my 89' LT , with the resistor, DR7EA,previous knowledge suggested that these were due to radio being fitted.
PO had D7EA with no resistor , I had no problems during the 3 years of use.
Kapt'n , I have found Repco , cheaper and easier to access these plugs , even if you have to wait a couple of days for stock to arrive in.

I seriously doubt that BMW recommend that DR7EA be fitted when a radio is fitted and if you do fit them then the system needs to be balanced as in source to load as I talk about above.

+1.........if so R plugs would have been recommended on all LT's.

Inge K. wrote:Grover and Kapitän.....all this about R or not is of course based on that you have
the genuine HT wires which have resistors integrated.

If the HT wires have been changed out things suddenly looks a bit different.

Yep... I'm following that Inge. My coils and leads are original. So I'll stick with the standard plugs. It's just that the bmw dealer gave me misinformation. I was a little sceptical but he assured me they would be suitable. Maybe he didn't realize I had a 2V engine.

What I'm finding is that even with the new plugs I'm getting hesitation on acceleration particularly when cold. This could be due to other reasons (I've just ordered the valve tool from the US to replace exhaust shims) but in the meantime I'll check my HT electrics but I can't even get the leads off the coils to measure the impedance. Can anyone point me to a thread or explain here how I go about testing my leads and coils. I've read Charlie's post #4 and Rick's post #22 and understand the theory. So here are a few Qs.

1. Do I measure the lead and plug together?
   
   
2. How do you get the HT leads off the coil?
   I'm assuming they just pull off but I don't want to pull too hard and damage something
   
   
3. How do I measure the primary and secondary windings ie which terminals?
   

Thanks

Measure them separately.
The HT leads will just pull out but they can be a bit stubborn sometimes.
The secondary winding is measured from one HT terminal to the other but also measure to earth (steel laminated core) to check for leakage to earth. That reading should be infinity.
The primary winding is measured across the green/yellow and black/blue on one coil and green/yellow and black/red on the other. Also check to the core to find any leakage and also should be infinity.

PS check inside the HT terminals for white/greenish powder as that means there is not a good connection and arcing is happening.

just a tip don't pull the plug wires

use the boot outer ,else you could stretch the internal wires and possibly cause an open circuit where it is joined to the metallic connector

the boots should release from the high voltage towers fairly easily , else some on has coated them with something and then pushed them on wet with the stuff  possibly gluing them to the towers ?

hopefully you will se bright shiney metal inside insyead of a green mess  like this



coils ends look like this once you get them out

 

the metal bit is where to measure from ,,,,to inside the spark plug end

terminals to measure

Thanks for that Rick
Just to confirm, I have the black coils with the brown towers. I think they are the original coils??

Leads (1) 5.32kΩ  (2) 5.06kΩ  (3) 5.17kΩ  (4) 5.36kΩ

Coil 1/4 - Prim: 2.2Ω  Sec: 11.92kΩ   (No earth leakage)

Coil 2/3 - Prim: 2.3Ω  Sec: 11.83kΩ   (No earth leakage)


Everything looks consistent and within range??
Only a small amount of corrosion on 2 of the HT terminals. I cleaned those up with a light rub of wet'n dry and electrical cleaner. Is it worth using a little dielectic grease on HT connections?

Is there anything else I need to know about coils, leads and plugs?

Thanks everyone for the info and assistance on this and your diagrams Charlie. I've learnt a bit this weekend. Cheers.

Sorry to the OP... I think I hijacked his thread and he did post a question (#21) which has gone unanswered.

Oliveri wrote:Thanks, you guys are are full of great info.

If I require to get a set of new leads at some point ( seen the NGK's for sale). Do they have resistors built in? If not, should I use an 'R' type plug once the leads have changed or will they cause issues with the coils.
Or simply 2V K = no 'R' plugs ?

We'll make him stand in the naughty corner and say Harleys are shit boxes 100 times, should give him a good work out.

NGK do make 5000Ohm resistor type caps, you will need to specify them when you order
Good plug leads are available from EME http://www.euromotoelectrics.com/category-s/978.htm
Realm engineering who also make RAM SHOX http://www.realmengineering.com/page15.html

good readings mate

dielectric grease ?  not any where near the terminals , but might be ok around the boots of the ht ON THE OUTSIDE of the boot - seal area

if you haven't already, get some deoxit and clean them with that ,  you could probably polish the spade type lugs on the primaries to eliminate the corrosion spots ....and or replace the spade terminals (at least clean them with deoxit as a minimum )   given that you have the right gear to do so .

those low volt terminals are hidden away in one of the worst places (including the earth terminals )...and often ignored  till after disaster has occurred . I really don't have the solution for protecting them but just know dielectric grease gets in everywhere and I think it is counter intuitive to slap some over them ....in other places in the world where they salt the roads (snow and ice stuff ) it would be a great prevention ,,,but out here ???? possibly some heat shrink fitted loose till the terminals are on proper ...then shrink them down to cover ?

good luck

Also, consider changing spark plugs once a year.

I find here in New England that the D8EA gives better fuel mileage, while the D7EA gives better performance.

...no problem, it has been interesting reading. Thanks again.

Just 2 cents from me:

I ran the bosch plug and got great performance, then the BMW mechanic guy did a service and swapped them out with the NGK D7EA/R. No where near as good performance but still acceptable.

One thing I learned is that, my engine, getting it @ 24 years old and 110,000ks on it (at least, complete with the K speedo intermittance fault!) was running OK when I got it, on original leads, but, wow . . what a difference  a new set of leads made.

When I did the rebuild that is exactly what I did . . . REBUILD. I practically replaced virtually everything you could, except the mill and ECU but this was, as far as I am concerned anyway, the best $28.00 performance enhancer I could have wished for.

I remembered a time when I had a Titan 500, 2 stroke Suzuki, needing and exceptionally clean and strong spark. . . . .

New leads are a god send to any oldish bike

a few of us have noticed the difference between the d7ea   and the dr7ea  (or d7ea/r )

that's I guess why most use or recommend them

all good to get some feedback in any case

Be made wrote:I remembered a time when I had a Titan 500, 2 stroke Suzuki, needing and exceptionally clean and strong spark. . . . .

New leads are a god send to any oldish bike

You are right about those old Suzuki twins. I had a T250 (1969 model I think). Ran well on Bosch plugs, but put NGK's in it and it would start missing after about 100 km. Put the used Bosch back in, and away it would go.

[quote="Rockman"][quote="Be made"]I remembered a time when I had a Titan 500, 2 stroke Suzuki, needing and exceptionally clean and strong spark. . . . .

New leads are a god send to any oldish bike[/quote]
You are right about those old Suzuki twins. I had a T250 (1969 model I think). Ran well on Bosch plugs, but put NGK's in it and it would start missing after about 100 km. Put the used Bosch back in, and away it would go.[/quote]


Since i have a Titan and it wont pull much over 105 kph in top, can you tell me what bosch plugs you used.

werewasi wrote:Since i have a Titan and it wont pull much over 105 kph in top, can you tell me what bosch plugs you used.

Have you put new crank seals in, they were a real bugbear in those 500s and the water cooled 750s.
I worked for Mayfairs in Brizneyland for about a year and used to do about 3 crankshafts a week plus as many of the 750s.

werewasi wrote:

Rockman wrote:

Be made wrote:I remembered a time when I had a Titan 500, 2 stroke Suzuki, needing and exceptionally clean and strong spark. . . . .

New leads are a god send to any oldish bike

You are right about those old Suzuki twins. I had a T250 (1969 model I think). Ran well on Bosch plugs, but put NGK's in it and it would start missing after about 100 km. Put the used Bosch back in, and away it would go.

Since i have a Titan and it wont pull much over 105 kph in top, can you tell me what bosch plugs you used.

The T500 had a top speed of at least 105MPH (over 160kph) . if tuned correctly with the autolube adjusted they cruised @ 4500 revs @ 70MPH with the red line at about 7000 revs (from memory - this was 1980 - 1981). If yours is not revving out and obtaining these speeds one thing I can think of is the exhaust headers may well be blocked up from too much round town running

Very definitely.

Exhaust ports and headers get caked up with carbon. We always cleaned 2 strokes every few months, like a new bike after it. The 500 was always good for over 100mph and a very nice ride. Petrol now seems to be bad too.

92KK 84WW Olaf wrote: Petrol now seems to be bad too.

Yeah that too. I remember when they changed it over here in NZ from Leaded only available to unleaded only, about 20 years ago. They had a terrible job getting the % of aromatics / petroleum right to get it to burn correctly. Even now, all these years later, I don't think they have it right. The "stand" time or shelf life of the stuff has decreased dramatically. With the old petrol it would run fine even after sitting for a couple of years.

The new stuff goes "off" after about 6 months or so and you have to drain a full tank (if you had one 6 months prior) and refill it with fresh juice

werewasi wrote: . . . can you tell me what bosch plugs you used. . . .

Sorry Man. I sold my T500 in 1982 and have not owned another 2 stroke since 1986.

My memory does not serve me that well

When we had 2 strokes the required octane rating was very low as they were not high compression. They would actually run with a parrafin mix which we used as an economy measure (if ones parents had it at home).

I wonder how 2 stroke crankshaft seals cope with ethanol and other stuff now in the petrol if one is leaving a bike sit for some time.

92KK 84WW Olaf wrote:When we had 2 strokes the required octane rating was very low as they were not high compression. They would actually run with a parrafin mix which we used as an economy measure (if ones parents had it at home).

I wonder how 2 stroke crankshaft seals cope with ethanol and other stuff now in the petrol if one is leaving a bike sit for some time.

Probably not too well.

When we changed over here that was one of the issues. I remember we had a lot of older cars leaking fuel from under the hood and catching fire due to the new fuel mixes destroying old carby gaskets

I can only assume it was just as tragic for the older bikes too

It took them quite a while to get it sorted out

92KK 84WW Olaf wrote:When we had 2 strokes the required octane rating was very low as they were not high compression. They would actually run with a parrafin mix which we used as an economy measure (if ones parents had it at home).

I wonder how 2 stroke crankshaft seals cope with ethanol and other stuff now in the petrol if one is leaving a bike sit for some time.

Paraffin, is that the stuff Harleys use?

The seals don't like ethanol, it rots them out just using it and methanol is a lot worse.

RicK G wrote:Paraffin, is that the stuff Harleys use?

Heh . . .makes you wonder about HD alright. But, seriously, Kerosene (paraffin) used to be cheap!. NOW it is 2.5 times or more expensive then petrol. We sell it here in the supermatkets @ $5.00 for a plastic bottled litre. Petrol is only $2.10 @ the pump so if you was running a hardley you might want to think about getting a beema :-)))