Hi all, just bought a 1986 k100rs, it's stood for a couple of years and was laid up as a runner, the old owner had a low speed off an it scared him so he laid it up, all the electrics work and I have a spark at each plug, I emptied the tank of the smelly old fuel and put some fresh in, fully expecting it to burst into life, but sadly it didn't, I suspect the fuel system but have no idea where to start, I have ordered a manual, can someone give me a clue as to where to begin please, the k100 is new to me

When you turn the ignition on do you hear the electric fuel pump in the tank going? Quite often the pump packs it in if it had not been used for some time.

ahhhhhhh, no noise from pump

If it is the pump the best idea is to replace it rather to try and repair. There are pumps from cars that are an ideal swap. Here in Australia our locally made Ford has a Bosch pump which is interchangable. Search through the search button in our forum and there will be some alternative. Also check whether the power is getting to the pump...and on yours it is the right side...under or beside the rear of the tank there is a connector. The wiri g goes in under the front right of the tank and runs the fuel level sender as well as the pump. Good luck.

Correct me if I'm wrong, but surely you won't hear the pump until you press the starter button and for a couple of seconds afterwards?
The power feed connector to the pump is a favourite to cause problems here.

You're right on that John and Stan you been smokin my weed again :smoke:

Forgot to mention that little button....sorry.

I guess Ainsjac didn't see the model year and was thinking Motronic, wasn't you Ainsjac.....?

Best to put it down to brain fade induced by old age. Perhaps too much blinker fluid today!

http://www.ebay.co.uk/itm/271624269655?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

and this

http://www.ebay.co.uk/itm/361090999598?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Found this on Fleabay yesterday, not much time left though.
Hope it helps.

oh right thanks telford is local to me too  re the first ad, there is no noises from inside the tank so I'm guessing the pump is an issue here, I've not looked yet but is it easy to get the pump out ?

Remove the the four screws holding filler neck lid to the tank and remove the lid.  Reach in and locate the fuel filter; disconnect the filter.  Feel for the tab of the clip that holds the pump support ring to the tank.  Squeeze the tab and the pump assembly should pop out.  There may be a hose from the filler neck to the pump filter screen that needs to be removed.  Remove the pump through the filler neck hole and disconnect the electrical wires.


Here's photos of the tank insides to show you how things are arranged.

ok thanks folks, the pump is out and seems to have had it, I bought a new one on ebay, how common is it for injectors to gum up ?? what should I be doing while waiting for the pump or should I just fit the pump and see what happens

Hi there !

Reading your initial post and the story about 'old gas' in the tank ?
My advice would be: get those injectors out, clean them up (see link below) and get some fresh O-rings. That's maybe an overkill right now, but it fill's your waiting-time in a very rewarding way. One day or another those old O-rings start leaking...

https://www.youtube.com/watch?v=VFJlTfHyrUk#t=56

Cheers mate !

Jos.

Very sound advice from GTJos. If you don't do it now you will be doing it later!!

yes indeed many thanks, this is just the info I need

If you're going to the trouble of replacing the injector O rings, order a set of new blanking caps for the vacuum take offs on the throttle bodies. Where you would attach a set of gauges to sync the injectors.
They're cheap and they do perish.

Comberjohn wrote:If you're going to the trouble of replacing the injector O rings, order a set of new blanking caps for the vacuum take offs on the throttle bodies. Where you would attach a set of gauges to sync the injectors.
They're cheap and they do perish.

 +1 !!

The small rubber parts won't cost much, take some extra in case you mess up on sundays. My luck now getting a K75 back to life

well, its alive....   very sweet it sounds too, cleaned injectors changed the pump and off it went, however I do have an oil leak, there is a hole under the gearbox where it joins the engine and its dropping oil though this, I presume the clutch is in here, I also presume the oil seal to the engine is leaking, would I be correct ?

Quite likely engine buy also could be gearbox, smell will tell.

not gearbox oil

good start andy congrats

sounds like output shaft seal (the o-ring behind the clutch basket nut ) to me , pretty common on older bikes

yes thanks, I'm quite pleased, it is only on 3 at the moment, but when I pulled the plug lead from number 3 to check the spark it was arcing all over the shop around the cap so I guess it's the problem, do I need the correct lead or will any one do the job ? the bike has only cost me £250 all in so far and that includes the new fuel pump, I need a new battery then once its got 4 cylinders i'll mot it, also the leak seems to have stopped but i'll have to investigate, is the o ring you speak of an easy job ?

Lets say that the O ring is best to happen in November than in April.

Unfortunately it means that you have to get the clutch off the engine, as in split the engine.

Its probably the biggest job on a K but having done it, if you do it right, you will be inspecting every part that could cause a problem down the road. At £250 though you are still winning. Its not a diy job for a lot of us, but if you have a workshop and reasonable skills its achievable. In doing it you will be eliminating all the potential downsides of the K and would have little problem selling it on to anyone on the forum with a history like that. Parts are not a big issue, you will be able to source them all easily.

My friend here is an ex BMW guy and he figures about 5 workshop hours to do it. That's in a modern workshop environment. You would need a bit longer doing it at home because you won't have all the parts on a shelf and will buy as you need them. You get a chance to inspect all of the splines and drive shaft, engine output splines, clutch. I know 88KE did this just before we went to France.

There are a lot of threads here on it. There are also threads on oil resistant clutch options, as in don't bother with the seal and leave it all until it gets on the clutch then change the clutch for the oil resistant one and just leave the seal alone. In the meantime park on main stand and keep it drained and it could be quite a while before it becomes an issue.

92KK 84WW K100RT 022575 wrote:Unfortunately it means that you have to get the clutch off the engine, as in split the engine.

I'm not a qualified mechanic but I have managed to fully rebuild my K from the frame. I found that the job we speak of here is really not that difficult providing you have some way of suspending the back end of the bike in the air while the rear end is removed - ergo . . . off it's main stand.

What I did, quite easily, was get some ratchet tiedowns like you use for securing loads on trailers, use the rafters in the garage, secure the front via the forks and the rear via the frame under the seat,

The hardest part, by far, I found, was jacking up the gearbox under the main stand to re-attach it and lining up the locating dowels

That and the centre nut on the clutch housing which is around 80 - 90 pounds torque. If you use the Haynes workshop manual from here: https://www.google.co.nz/#q=k100+workshop+pdf

and just follow along in the sequence supplied then it is a reasonably easy job

Its not a diy job for a lot of us, but if you have a workshop and reasonable skills its achievable.

Be made has put it very well.

Don't be put off by the job because your still quids in as they say.

92KK 84WW K100RT 022575 wrote:
There are also threads on oil resistant clutch options, as in don't bother with the seal and leave it all until it gets on the clutch then change the clutch for the oil resistant one and just leave the seal alone.

Although....if going in to change a clutch, its not very much more work to replace the seal....and the oil proof clutch plates are rather expensive. 

your bike is German....dont subject it to the shame of an oil leak, its not British  

Anyways, I had absolutely no problem at all replacing the main oil seal. piece 'o piss as it were. Biggest hassle is the strip down and rebuild....and I tend to take the view that "well, if im this deep in, I may as well do job A, B, C, D and E while Im there....

so when you say you have to split the engine, I took it as having to split the cases ?? I initially assumed that when you took the clutch off the seal would be behind it, is this the case, I have a decent workshop and it won't be a problem, the bike came to me cheaply, I'm not going to be going mad with it, just get it an mot and ride it, when it stops I fix it my main thing is vintage brit its just nice to have something that isn't 80 years old, I bought a cheap r80 a while ago, it was knackered but I loved it, I had an 1150gs also, that was nice too, I'm looking forward to riding this

Going on your last post the seal job will not be a problem. Its a case of doing splines and more when you are in there. That's all.

Going on your last post the seal job will not be a problem. Its a case of doing splines and more when you are in there. That's all.

I dont think you need to split the cases.

I did when I did mine but thats because I was also replacing the output shaft. (only removed the seal when I split the cases, the new one was installed with cases back together. 

I recall seeing little jigs people have made up to extract the old seal, and then putting in the new one is just like any other oil seal.

thanks guys, you've all been a big help, but first things first I need 4 cylinders working, its in a state to be mot'd as it stands pretty much, i'll take some pics tomorrow, its obviously a little scruffy for £200 but its not too bad, its a quality item, built to last.... I like that

floyd wrote:I dont think you need to split the cases.

That is correct

You do NOT split the cases

Just remove the clutch housing. Behind that lies the large centre nut etc. Get the O'ring off then gently (if there is such a word in stubborn mechanical things) pry the old seal out with a couple of large screwdrivers. When you have it out tap the  new one in evenly. I used a Large diameter socket which met the diameter of the seal.

Before you proceed with any of this do the following

Make sure you have:

• Some 60+ % molybendunum grease on hand for lubing the splines, the clutch pushrod and G'box, output shaft, drive shaft at both ends and final drive spline
  
• Tourque Wrench for the clutch reassembly
  
• Loctite or similar for the final drive centre nut on the clutch housing. Haynes will say replace it is a one off useage but the workshops just loctite it
  
• Antiseize nickel paste for all the bolt replacements
  

If you are going this far you may as well do the basic major service items while you are there and then get the benefit of peace of mind and less trouble and more troublefree running for longer periods

andyo wrote:yes thanks, I'm quite pleased, it is only on 3 at the moment, but when I pulled the plug lead from number 3 to check the spark it was arcing all over the shop around the cap so I guess it's the problem, do I need the correct lead or will any one do the job ? the bike has only cost me £250 all in so far and that includes the new fuel pump, I need a new battery then once its got 4 cylinders i'll mot it, also the leak seems to have stopped but i'll have to investigate, is the o ring you speak of an easy job ?

First replace all the leads.

What I did was remove them all, take them to any autoparts supply shop and get standard car leads of the correct length. Cost less than $30 nzd.

If yours are the originals they will have resistor built into the lead caps. Standard car ones don't so you will need to replace the spark plugs with R for resistor in the plug name . . so . . ngk I think it is dea7r or similar others can help heeer

Fit the plugs and leads and if it is still missing then come back to this thread and one way or another members will help you until it is fixed

You will want a fully charged good battery before further testing

Hi Andyo
Would be worth reading this thread covering spark plugs and (at post #30) testing coils and leads.
https://www.k100-forum.com/t8900-new-spark-plugs

The plugs Be made mentions are NKG  D7ea for use with resistor caps or alternatively DR7ea if you replace with standard lead.

Note also you will need the little round things that screw on to the end of the plugs if you are changing leads. If your old plugs don't have any you will need to source some because the NGK's you will require do not come with them fitted. Most lawnmower and cycle shops have spare plugs they can strip them off for you, usually free unless you strike Mr tightarse

I think most folks refer to them as bobbins

ferules also applies I guess

nibblets, they still come fitted as far as I know here in the uk

I appreciate all the help by the way

I used NGK D8EA here as every place I go has fitted them and the K100 came with them back in 2010. Never a problem with them. Forum always says 7 and not 8. Even Halfords keep them. Very cheap. I have twice had a new one fail so if you replace a plug with a new one and still have a problem try another just to be sure.

But, over here they don't come with the ferrule bobbin nibblet or beer.

Before going too far swap the two coils, they are interchangeable, to make sure the fault stays on no 3. If it stays its the lead/plug, if not them its the coil. Cheap enough too off eBay or parts.

If you are getting leads made up make sure the caps have the long tab on them so you can pull them off.

The bobbin on Bosch plugs doesn't unscrew.
Just in case.

Comberjohn wrote:The bobbin on Bosch plugs doesn't unscrew.
Just in case.

this I have just discovered

Comberjohn wrote:The bobbin on Bosch plugs doesn't unscrew.
Just in case.

Oooh. for some reason in my shed I have some Bosch plugs....no bobbins on them....

On a more serious note this is a really good thread because its taking you through all the things you could find by way of a breakdown and afterwards find that in fact they are easy to do now that you have learnt about the K.

Go on a trip and break down and in nearly every town there will be someone with a K that can offer some help or a few basic spare parts, or an address to have some posted to, or will know someone who an do some repairs. I love that about this forum. If you do a trip to Ireland let us know you will be coming, that way if you get any problems there will be someone to point you in the right direction or find a good pub waiting room while your puncture K is repaired.

new leads and plugs but my dead number 3 cylinder remains, I did actually ride it a couple of miles in the optimistic hope that it would somehow burst into life, but of course it didn't, so tomorrow I will be revisiting injector number 3, I will be checking the wiring after spotting some damage to the wiring rubber boot on this cylinder, is it possible to check with a normal digital meter the power to the injectors? do they have a permanent live and switched earth or the other way around ? either way I'm going to be messing with those fiddly wire clips that hold the wiring plug on, am I missing something or is there an easy way to get them off, I've tried to add a picture hopefully you can see it, its a fairly standard issue neglected, abused and strangely worthless  k100rs, I bought it because it was cheap (£200) but I actually quite like it

andyo wrote:new leads and plugs but my dead number 3 cylinder remains, I did actually ride it a couple of miles in the optimistic hope that it would somehow burst into life, but of course it didn't, so tomorrow I will be revisiting injector number 3, I will be checking the wiring after spotting some damage to the wiring rubber boot on this cylinder, is it possible to check with a normal digital meter the power to the injectors? do they have a permanent live and switched earth or the other way around ? either way I'm going to be messing with those fiddly wire clips that hold the wiring plug on, am I missing something or is there an easy way to get them off

I think the earth is switched. You cant test with a multi meter as the pulses are to short. You need to make a little LED probe.

Alternatively, take out the injectors but have them plugged in and turn the engine over, you will see the injectors spray (or not). move number 3 to a different connector on the wiring loom and see if it now sprays. if it sprays the prob is the wiring to number 3 and not the injector.

thanks Floyd
https://i.servimg.com/u/f74/19/04/89/15/20141011.jpg

andyo wrote:new leads and plugs but my dead number 3 cylinder remains, I did actually ride it a couple of miles in the optimistic hope that it would somehow burst into life, but of course it didn't, so tomorrow I will be revisiting injector number 3, I will be checking the wiring after spotting some damage to the wiring rubber boot on this cylinder, is it possible to check with a normal digital meter the power to the injectors? do they have a permanent live and switched earth or the other way around ? either way I'm going to be messing with those fiddly wire clips that hold the wiring plug on, am I missing something or is there an easy way to get them off, I've tried to add a picture hopefully you can see it, its a fairly standard issue neglected, abused and strangely worthless  k100rs, I bought it because it was cheap (£200) but I actually quite like it

Just checking you tried swapping the coils before you go at the injectors? If its the coil the leads and plugs wont cure it.

yes mate I've tried it all ways, the one coil does 2 and 3, 2 is fine I swapped the leads between 2 and 3 first,  I've got a whopping spark and just for good measure I did swap the coils too, still number 3 I'm afraid

I hope I didn't sound pedantic, but that the way you have to be with the K or you get tripped up somewhere.

Your work in sorting this is more time than money but once you have it sorted you will have a very reliable bike.