The fall broke off the negative terminal. I was going to try and tap into what I thought was what was left of the post. I started to drill and the filings didn't look like metal, they weren't. I tried to pick them up with a magnet, they didn't pick up. I thought this very odd, since it doesn't look like the post makes a metal to metal connection. The only thing I can figure is that they system works similar to my electric tooth brush which has no outside terminals. The only thing I can figure is that the coil picks up the electrical current through the plastic. Can anyone enlighten me on how the coil works?

My problem is:

New a coil looks like it costs in the area of $263, which I can't afford.

Can my coil be repaired in some fashion with epoxy putty? Or, the metallic engine epoxy putty?

I know the answer is to get a new or used one. However, the boneyard doesn't have one. Nor does Kbikeparts (he doesn't answer emails so I don't know if he's reliable?) For now I'd just like to get the bike running. I have so many other needs on the bike the expense is just too much right now.

There is a picture of the broken post on my blog, http://1985k100rsre-build.blogspot.com/

I'm going to try and post a picture here



Thanks to all for your help

If you want to contact Drake from kbike parts go to the motobrick.com forum and he is frankenduck.
Also here is a set on fleabay http://www.ebay.com/itm/1988-BMW-K100-K100RS-COIL-COILS-/221031679551?fits=Make:BMW&hash=item337683c63f&item=221031679551&pt=Motorcycles_Parts_Accessories&vxp=mtr

ouch paul !!! thats a difficult one

what happens is that there is a fine wire welded to the post that then goes to the coil bobin ....yes inside that epoxy black assembly .

you could get maybe a dremmel tool and cut away the epoxy ..really carefully ...

you will have to find the copper wire in there somewhere ...at least identify where it is

possibly with a lot of luck you could solder another piece of wire to the remains of the tail comming from the coil ...but be aware they are a coated copper wire ....usually with some kind of varnish substance covering the actual copper , so you will need at least 3mm of wire exposed to get something joined onto it ....(soldering ) you could then get a similar cross section of copper wire and then solder it to the post ...the method i would use is to tin the post before hand as it will take a fair amount of heat to get a bond with flux to the post , solder the new section of cable to the post ...and pretinned section of that wire to the pretinned section of the recovered wire ...then carefully manouver the whole assembly into about the right place .

you will need to buy some "3m" epoxy ( for electrical purposes ) comes in small bags which you pull apart to mix the two sections (catalyst and resin ) the whole bag gets really hot with the chemical reaction ..be carefull

you will have neede to make some kind of former to surround the post and body of the coil assembly that will retain the hot epoxy till it goes off ...starts getting cool after about 15 minutes ...

then after its all done ...some trimming up of the epoxy would make the thing at least looking like its all together and functional .

the reason for the epoxy is so that there is verry high insulation characteristics from moisture ...air and all that stuff .....15 ,000 volts will jump a long way in air ....even further in moist air ...and corrosion is not something you want to have happen inside all the high voltage areas

i would use some form of thin metal possibly super glued to the coil body as a former whilst the process is cureing

the really hard part will be ,,,if the epoxy binds to the old coil body epoxy at the join and doesn't fracture over time ...you might concider a fairly large area for the former and some form of cleaner to the old epoxy of the coil to help this along ...maybe some advice from the 3m folks could help in this regard ?

there is a product called "episolve" that will eat away at the epoxy over time and not affect the copper too much ....have used it years ago ..but dont know if its still available for purchase to the public ...its kinda nasty stuff ...

its going to be a fiddly job and some reasonable expense for the epoxy and solvents but under $50 should cover it

hope that helps

That was kind of my thought for the fix charlie, I've done some epoxy work on boats and yes a small mass of epoxy can heat up to amazing temps. Unfortunately, I don't see any place where a fine copper wire might be hiding. Finding and getting 3mm free seems nearly impossible. I think I have to take Rick's suggestion and try ebay.

Rick I appreciate the search. I usually discount ebay instantly. I've never had a bad experience but usually go to Craigslist for my photo and computer needs. I can touch and feel the product.

The link you gave me is from an 88. I know very little was changed on the bikes would that include the coils? I think I'll go ahead and grab them while their available once I hear from you.

Thanks again guys

Since it`s a -88. model coils you can use it (all 4cyl. 2V) is similar.

And since it got orange (instead of black) HT terminals,
it`s the revised model which should be better.

Here is a pair of the older version, a bit cheaper.

Grab em they work. They were an upgrade and the older ones were superceeded by them.

Phoenix,
I've got a working coil from my 1985 K100RT. PM me and I'll make you a good deal. Dennis

The $40 link you sent me looked just like the ones on my bike, old and pretty bedraggled. My other coil, the one that didn't break has one of the sockets that was dark and had "greened" the copper on the spark plug wire and seemed suspect. When reading the forums they always say something like "a good/healthy spark" when testing the plugs. All my plugs/wires/coil connections gave a spark when tested. I'm not sure the spark was all that healthy, we'll see what it looks like with the new set of coils.

Dennis, thanks for the offer, I wish I'd seen your post earlier, I would've like to cut my costs. But, I'm hoping I'll have some peace of mind with these newer coils. Now I'll have a backup

Rick and Inge, how are you doing your searches on ebay? Although, I didn't search for coils specifically, when I searched for BMW Parts; the parts you linked me didn't show up. Are you using, have you used Search Tempest?

Charlie: I am going to try the metal epoxy (JB Weld?) rebuild. I did find the little copper wire in the plastic shroud. I spent some time trying to expose it. There is no way I'd get enough to solder. It's mostly just going to be an exercise now that I've bought the other set of coils.

Thanks to all who helped

I always seem to be thinking of the next bike! And I haven't even ridden this one. But, with all the research I've done I've learned alot about the K's. However, there's nothing like first hand info: You all have many varied bikes, I'd value your input

I think of myself as pretty much as a Tourer. I used to own a R100RT, 30+ years ago. I thought it was smooth until I rode a friends Goldwing. It was nice but they are big and heavy, not as good on the back roads that I like.

Which bike would be a better choice for me (assuming I get the Phoenix running, restored and want to sell it). Even if I hit the lottery, I don't think I'd buy a K1600 it's too like the Goldwing, too big I think for me. But that won't happen

I think I'll always have constraints on my bike purchase, it would have to be a used bike.

The K's are said to vibrate? It seems they didn't cure that until the K1200. Is that correct?

One thing I really dislike is that the newer bikes need to use Hi-test fuel or even super. I like great gas economy. It seems to me even if you're getting great MPG, if the bike runs super, it's somewhat a false economy. What years to the bikes start using hitest? Does my 85 need hi octane?

It also seems that there are also clutch and drive spline issues. It also seems that this was addressed in the 1200. I haven't checked the splines on my bike yet, I've read the forums and watched you tube videos. It doesn't seem to be that difficult, wow every 10K, that seems very Un-BMW. But I doubt I'll do more than 2K a year. So it may not be a big issue. Do you find it an issue on the K1100? K1150?

What year did they start making the K1200? I don't need to much power or speed. I have a VT1100 and find it has plenty of power and acceleration.

The clutch issue seems a bigger deal from what I found online it looks like you need to get the engine out/ frame off. Is that true? Or, is that just the one post I read?

It seems that for vibration issues the best bet is to go to a K75? For better fairing coverage make it an RT? That leaves the clutch issue.

Thanks for any personal wisdom or links.

Rick

drive splines ? dont worry about it ...just do the recommended lubrications and it will last a long long while ....

lets put this in perspective ...when was the last "big bike chain" that you bought ....and how much was it ?...now figure in a change of front and rear drive cogs every 2 or 3 chains ....all in all i would say that the bm is in front but not only in cost and reliability ...but clean and neat ,no splatter of oil all over the place . the spline lube might take all of 2 hours the first time ....but under 30 mins when you have done it more than once .

crikey i did over 30,000 killometers in the last year and a bit ...and on a 25 year old bike !!! yes maintenance was needed and still is ...parts are available and cheep ....

vibration ? dont worry about it ...now were getting picky ...almost all bikes have a sweet spot ...and i cant remember out of some of those over 2,000 k weekend rides, anybody saying the vibration was killing them.

you must weigh up the benifits and negatives ....but i can tell you, it is most rewarding when riding through a town ...any town, you will draw turned heads ...many in appreciation and respect ...when there is more than 4 of you in a group, that effect is amplified ...quiet, sleek and with that typical cam chain whistle (under 3 grand ) call it a signature of almost all overhead twin camshaft multis ...remember the kwaka 900 , the boldor 900 hondas ?

better to have that signature than the dry clutch rattle of a recent ducatti ...giggles

in other words ...enjoy your ride ...be proud you have a "k" and its on the road and running sweet ...i dont think there is any better personal reward !!!!

I love it. Thanks Charlie. Nothing like a man or woman who loves their bike. I can't wait to get the K running. It's funny, I hadn't ridden in 30+ years, my wife didn't like motorcycles. I bought the Honda Sabre 1100 (shaft drive). My wife liked it so much she decided to ride and then said she might like to learn to ride! When I got the K, she just didn't understand. The sabre is newer, garage kept, running, shiny and I still love the beamers. I'm looking forward to being as much of a fan as you are about the K bikes.

phoenixk2b wrote:One thing I really dislike is that the newer bikes need to use Hi-test fuel or even super. I like great gas economy. It seems to me even if you're getting great MPG, if the bike runs super, it's somewhat a false economy. What years to the bikes start using hitest? Does my 85 need hi octane?

Since fuel is mentioned..........if possible try to get fuel without ethanol (only super w/o in Norway), as this attacks the rubber parts in the fuel tank in our old girls.......unless these parts allready have been changed out earlier.

And early models needs a lead substitute.......this was up to early -85. on Euro models,...not shure when the change was on US models.

The vibration damper had literally melted into a putty like substance. I don't know if the new parts are any better than the old; since I used a Facett-Purolator fuel pump and had to use marine fuel hose to take up the extra space in the fuel pump mounting hole. Since I'd done the upgrade once, any future work I do in no time. I found remnants of at least one other bad fuel hose in the tank, making my replacement the third, since I took off a fuel hose.

I don't think non alcohol fuel is available in the US. I think the only way to get leaded fuel is to use a supplement from an auto parts store.

Phoenix, as annoying as the K gremlins can be, I wouldn't give mine up. It's attached to a sidecar and works great for that. When it's running well, there's nothing like it. I've had people from Germany come up to me and show me pictures of their BMW's back home. Others stop to talk about their lifelong desire for a BMW. That said, my 2 wheel bike is a 2006 Triumph Tiger 955i. It's a fantastic touring bike, not bad on maintained off-pavement roads, flicks around pretty well in the twisties, kind of like a sport SUV of motorcycles. The 2007 to present Tigers are a bit more like a sport bike with an upright sitting position, but still amazing bikes.

Sorry I didnt see the post sooner. I have a garage full of K100 parts and bikes. Even have a turbo for the K100. If you need other parts for the K100 keep me in mind. If you want to do side by side restos or even a fleet of them I have 3 rollers here that can be restored. Also 2 up and running 1985 RSs. Trying to thin the hurd and make room. If you had alot of gunk in the tank keep in mind I also clean and test Fuel injectors for the K and R bikes. (shamless plug)

I took a look on the net and found some you tube postings. I didn't build a fancy machine like the one guy. I took a simple approach. I found a syringe at wall-mart used for mixing 2 cycle oil. A friend has a shop, I got an injector electrical cap from him. I used a switch from an old computer. Using my old fuel hose on the syringe and injector I was able to pressurize they system and use the switch to control the flow. I blew the injectors out from both ends. I checked around and looked for a sample of the spray pattern but couldn't find one. My injectors seem to be shooting cleaning fluid like a squirt gun, stream vs. spray. I did find one note that said the low pressure might not be enough for them to do their spray? After I get the coils and try to start the dang thing up, I may be giving you a call. It's all up to UPS to do their thing.

Hey Ron, Do you have a right side mirror pod for an 85 RT? The one on my bike was broken when I bought it and have been watching boneyard for one but no luck. I would buy a complete pair if it would help.

KFilipow

That is not a great way to test the injector. All that will show is if it is opening. You can not check the flow rate or leak test the injector. Also there is a screen in the injector that should be changed. The o rings are old and dry so they should be changed. Also the new o rings are better then the old ones and can handle the ethanol in the fuel. There is a lot more to what I do when I service an injector. If you want more info on what my service includes you just need to ask.

Kfilipow I do have mirrors here. Give me a call. I am only avaliable here till fri. Then I am off to the MOA rally. So if you need them quick call me before Fri. Ron @ (732)742-6007