My K-100RS (87) sat for about a year unfortunately do to a cross-country move  back to Canada from California. 

I replaced the battery as it was clearly dead. Now, i think the issue I am having starting it up is the possible bad fuel (it had a little bit in the tank when it was transported and sat in storage till a few weeks ago).

I am told, remove the gas tank, replace the fuel line or try fuel starter.

I don't have a strong mechanical background - my most complex motorcycle repair was replacing brake pads and regular oil maintenance type of stuff. I looked at the bike, and with the fairing stuff in the way, I am not sure exactly how to remove the fuel line and tank. I could not find any clear instructions and/or youtube videos on how to do this for my model - the examples I find are all much simpler and easy to access ones without all the fairing that my rs seems to have.

If anyone could point me to a video or a step-by-step how-to it would be really appreciated. I really want to learn to do this on my own. Worst case happens I screw it up and I throw it on a trailer and take it to the shop.

So, should I even bother trying to do the fuel start approach? Does this spray go in behind the air filter? Or should I just go directly into replacing the fuel line and removing the tank to empty it?

thanks for the advice

You have a two valve (2V) model K100. When you want to do your own work, you need to have some manuals. Download the BMW K100/K75 workshop manual here. Download the Haynes K100/K75 2V manual here. Purchase a Clymer K1100/K100/K75 manual somewhere. Between those three, YouTube and forum input, you should be ready to go, if you have some tools.

OK you have some Knohow so keeping things simple,why not syphon what fuel is 
left,use absorbent clothes to cleen the tank out,put a gallon of good fuel in and see 
what happens.With a bit of Lady Luck it might start  Good Luck

Take the filler cap off (four screws will give you better access)
Siphon out the gas best you can. Remove the fuel pump fuse for safety reasons(I think it is fuse six but check).
Get a large syringe or cheap turkey baster, Pull the fuel pump out by depressing the tab on either side of the vibration isolation. This will allow you to clean up an gunk that was worked its way to the bottom of the tank. Wipe down any other part of the tank you can reach. rinse with fresh gas and suck that out too.
Fill with fresh fuel and hopefully it goes. The next set for me would be to remove all the fuel lines and flush them. Order a injector tuneup kit and change the screens and o-rings or send them out for a cleaning.
Hopefully part two is not required.
Much of this is a repeat of what others have already said but hope it helps.

ohh and remember to reinstall the fuel pump fuse.

You can remove the fuel tank fairly easily. 

First, remove the left side knee pad.  It's held in place with two screws at the top and one at the bottom.

Second, Remove the battery covers and unplug the the electrical connector to the tank.

Third, remove the seat.  It is held in place by three "C" clips(two on the seat hinges, and one on the support arm.

Fourth, there are two large "C" clips holding the rear of the tank.  Pull them out.

With the seat off and the kneepad out of the way, you can lift the rear of the tank and slide it back 3 or 4 inches.  That will let you get to the fuel lines and the clamps that hold them on the tank. 

I put a big wad of paper towels under the lines when I pull them off to soak up the fuel that leaks out when you disconnect them.  The clamps have slotted screws to tighten them.  It's easier to use an 8mm socket on a 1/4" ratchet to loosen and tighten the clamps.

With the lines off, you can now pull the tank back and up.  There may be 1 or 2 additional drain lines under the tank that you can pull off. 

The tank is now off the bike and you can work on it at a workbench.

Once you've sorted out the how-to of removing the tank to access the fuel hoses, try fitting some sealed quick disconnects for easier removal later on - from BMW quite expensive for the four-piece OEM set from an Oilhead, or readily available aftermarket from eBay or an auto parts store - facing opposite one another so you don't accidently connect the gozinta hose to the gozouta hose when reassembling. Getting QD's that are sealed at both ends allows you to keep the fuel system pressurised so no petrol spills on your engine or fancy duds.

Plastic = cheap, known to snap
Brass = £128 a set from Motorworks (wince)

Ah yes they Turkey baster trick! I had forgotten about that - used that once before on my old land rover to do something similar.
Will give that a try first before removing the tank, heck of a lot easier. I also have a KTM 690 Enduro which had the same issue, but after leaving some fuel conditioner overnight and then putting in some fresh gas, fired right up.

Thanks all for the suggestions - clearly going to need those service manuals.

Dai wrote:Plastic = cheap, known to snap
Brass = £128 a set from Motorworks (wince)

BMW's new (several years old) set now use a metal side connecting to a plastic side. The male end was known to snap over time and get stuck inside the female side.  

Proper protocol is maintained now.

13 31 7 659 120 x 2 - female side with quick release button
13 53 7 700 800 x 2 - male side metal, no more breaky
16 12 1 176 918 x 4 - Oetiker style clamps, or use mini hose clamps that don't pinch the 8mm fuel hose

All of the above will chew through a US$100 greenback like a hungry caterpillar on a new, Springtime lettuce leaf.

I'm pretty sure I can buy at least two or three rolls of paper towels to mop up the spilt fuel for $100.

Point-Seven-five wrote:I'm pretty sure I can buy at least two or three rolls of paper towels to mop up the spilt fuel for $100.

You can, at least in our local grocery store - Fred Meyer - where at long last they have a selection of store-brand TP for sale!

Jokes aside, it really does make it easy to not have to depressurise the fuel system by using QDs when performing maintenance or worse, an unexpected roadside repair. Too, QDs are common on racing/performance web sites and can be had in a variety of ID's for hose size for far cheaper than BMW, Motorworks, 'Bins or other. I have them on all of my F/I BMWs except for the low-tech Airhead.

So if I bought the cheap-o-plastic ones how often would you have to change them to avoid breaking? I could be very careful with then knowing their weakness.

Siphoning out all the fuel, putting in fresh fuel didn't do the trick.

Next attempt is the fuel lines I guess. Have to get one of those printed manuals now.

I am not sure why you were advised to remove fuel lines. If the fuel pump is working, and you put fresh fuel in the tank, that fresh fuel will have run in a loop via the return hose, flushing out the lines.

Is the pump running? It only runs when the motor is turning, either running or when starter motor is engaged. ( Unlike most modern fuel injection systems which run when the ignition is first turned on). If you open the fuel filler and look inside the tank whilst trying to start the bike you should be able to hear the pump plus see fuel circulating in the tank. If not running check the electrical connection under the tank, check the fuses, etc.

Sometimes idle pumps get stuck. If not running it needs inspection. It is easy to remove the pump by simply removing the filler cap assembly (4 screws) and reaching inside. The pump can be removed from the tank and disconnected to be tested on the bench. Sometimes a stuck pump can be freed up and reinstalled. Otherwise a new pump is needed. Change the fuel filter too while you are working inside the tank.

One other thing.... Many have said that K bikes loose compression while sitting for long periods. In order to restart it is said that a little oil squirted in each spark plug hole works wonders. I think Chris Harris has a video of the on YouTube. Remove plugs, use only a little oil, replace plugs then try again.

Good luck!

Michael Sydney wrote:I am not sure why you were advised to remove fuel lines. If the fuel pump is working, and you put fresh fuel in the tank, that fresh fuel will have run in a loop via the return hose, flushing out the lines.

Is the pump running? It only runs when the motor is turning, either running or when starter motor is engaged. ( Unlike most modern fuel injection systems which run when the ignition is first turned on). If you open the fuel filler and look inside the tank whilst trying to start the bike you should be able to hear the pump plus see fuel circulating in the tank. If not running check the electrical connection under the tank, check the fuses, etc.

Sometimes idle pumps get stuck. If not running it needs inspection. It is easy to remove the pump by simply removing the filler cap assembly (4 screws) and reaching inside. The pump can be removed from the tank and disconnected to be tested on the bench. Sometimes a stuck pump can be freed up and reinstalled. Otherwise a new pump is needed. Change the fuel filter too while you are working inside the tank.

One other thing.... Many have said that K bikes loose compression while sitting for long periods. In order to restart it is said that a little oil squirted in each spark plug hole works wonders. I think Chris Harris has a video of the on YouTube. Remove plugs, use only a little oil, replace plugs then try again.

Good luck!

Yeah today's job is to remove the pump, not the tank. I will also try and find that video mentioned.

gurka wrote:Yeah today's job is to remove the pump, not the tank. I will also try and find that video mentioned.

If you can hear a whine for two seconds after you release the starter button, the pump is operating. The unknown is whether fuel is coming from it.

If you hear that whine, then go get some fogging oil at an automotive store, spray it into each cylinder then try starting the moto, if the battery has a full charge.

Laitch wrote:

gurka wrote:Yeah today's job is to remove the pump, not the tank. I will also try and find that video mentioned.

If you can hear a whine for two seconds after you release the starter button, the pump is operating. The unknown is whether fuel is coming from it.

If you hear that whine, then go get some fogging oil at an automotive store, spray it into each cylinder then try starting the moto, if the battery has a full charge.

Yes the battery is brand new - just installed it a few days ago. I think I can hear the pump running, will post a video shortly so you can see it.

I also got some fuel starter - would this not serve the same purpose as the 'fogging oil'?

gurka wrote:I also got some fuel starter - would this not serve the same purpose as the 'fogging oil'?

No. That is why fogging oil was recommended. I'm just trying simple measures to start this relic before you go down the rabbit hole of disassembly. Stuck rings are only one of several relatively simple problems that could be affecting starting. I don't know what fuel starter is but if you're referring to starting fluid, it can wait until later.

Piston rings of stored engines can seized. Seized rings don't provide sufficient compression to ignite fuel. Fogging oil provides a fine mist that can penetrate corrosion binding rings in pistons. Freeing the rings restores compression to help ignition. You'll need a spark plug socket, socket extension and a ratchet wrench and the basic ability to reinstall spark plugs without cross-threading them.

Laitch wrote:

gurka wrote:I also got some fuel starter - would this not serve the same purpose as the 'fogging oil'?

No. That is why fogging oil was recommended. I'm just trying simple measures to start this relic before you go down the rabbit hole of disassembly. Stuck rings are only one of several relatively simple problems that could be affecting starting. I don't know what fuel starter is but if you're referring to starting fluid, it can wait until later.

Piston rings of stored engines can seized. Seized rings don't provide sufficient compression to ignite fuel. Fogging oil provides a fine mist that can penetrate corrosion binding rings in pistons. Freeing the rings restores compression to help ignition. You'll need a spark plug socket, socket extension and a ratchet wrench and the basic ability to reinstall spark plugs without cross-threading them.

Ok I understand - yes the starting fluid is a deeper hole I'd rather avoid if can be.

I have all those tools - even though I'm not experienced in mechanical bike stuff, I do own a land rover and have done large projects like replace the tranny and tcase, diff locks and other stuff like that on that truck. You can learn a lot on Youtube these days and with LR club mates who have lifts to get the big stuff done properly.

Fuel starter AKA eaststart is a ether, based product that is not recommended
except on old DIESEL engines follow the advise given on the forum,it is the best tried tested and proven information you can get,Older wiser heads will teach you
LOADS .

moriarti wrote:Fuel starter AKA eaststart is a ether, based product that is not recommended
except on old DIESEL engines follow the advise given on the forum,it is the best tried tested and proven information you can get,Older wiser heads will teach you
LOADS .

I managed to find Fogging Oil...

Removed the plugs, sprayed Fogging oil. Still won't turn on. 

video of startup: https://streamable.com/vo6g7x

Pump sounds like it's working well - don't think the issue is there.

Next?

What do the spark plugs look like after your attempt to start the engine?  Are they wet?  Are they black?  Are they black and wet?  Did you replace them recently? 

Do you get a good spark when trying to start the engine?  I just recently had the engine in a bike I restored foul the spark plugs with a rich mixture.  The plugs would spark out of the engine when I tested them, but wouldn't when they were in the engine and under the compression in the cylinder.  Even after I corrected the over rich mixture, they wouldn't fire.  It wasn't until I got new plugs that the engine would start properly.

gurka wrote:video of startup: https://streamable.com/vo6g7x

That was shot like a ghost-hunter reality show. Spooky and compelling viewing!

Laitch wrote:

gurka wrote:video of startup: https://streamable.com/vo6g7x

That was shot like a ghost-hunter reality show. Spooky and compelling viewing!

LOL i know sorry - my cat kept jumping on my leg and he's a barn cat with freakishly long nails.

I looked at it after posting and was like WTF was that.

Point-Seven-five wrote:What do the spark plugs look like after your attempt to start the engine?  Are they wet?  Are they black?  Are they black and wet?  Did you replace them recently? 

Do you get a good spark when trying to start the engine?  I just recently had the engine in a bike I restored foul the spark plugs with a rich mixture.  The plugs would spark out of the engine when I tested them, but wouldn't when they were in the engine and under the compression in the cylinder.  Even after I corrected the over rich mixture, they wouldn't fire.  It wasn't until I got new plugs that the engine would start properly.

They were very new - replaced about 2 years ago. I cleaned them up with alcohol just to make sure also no grime went back in.

gurka wrote:my cat kept jumping on my leg and he's a barn cat

Speaking of that, take a flashlight and verify that mice haven't been nesting in your muffler then peep into your airbox, too.
Maybe it'll start tomorrow, tomorrow. It's only a day away.

Laitch wrote:

gurka wrote:my cat kept jumping on my leg and he's a barn cat

Speaking of that, take a flashlight and verify that mice haven't been nesting in your muffler then peep into your airbox, too.
Maybe it'll start tomorrow, tomorrow. It's only a day away.

The bike only landed back here from California where I was living for the past 3 years and sat for the past 12 months without being ridden. It was running perfectly before, a lot of upgrades were done, new tires, brakes, and it took me all over California with the only issue being the speedometer kept going to zero every once in a while but would always reset. I figured it needed a new cable so ignored it for now - was planning to fix this now, but the damn thing won't start now.

gurka wrote:I figured it needed a new cable so ignored it for now - was planning to fix this now, but the damn thing won't start now.

It's just as well; there is no cable to replace.

LOL meant speedometer.

A compression test  would help to prove good or bad cylinders, :DTest 1 dry, Test 2 with fogging oil 

G'Day and Welcome Gurka.

Have you tried bump starting?

I always look at the following when an engine wont fire. Some of this you have already done and I am sorry if I am telling you how to suck eggs.

Fuel - clean fuel, fuel pump - connector/fuse, recirculating in tank,fuel at rail, fuel at injectors

Spark - battery charge, check for spark at plugs, check leads and connections (easy to install leads wrong way round) check for condition of plugs after attempting to start as above.

Air - check airbox/filter as above

Compression - fogging oil, compression test (I have never got this far, it has always been something in fuel or spark for me)

The fact it was running not long ago will give you confidence, it will probably be something simple.

Plenty of troubleshooting info here.... 

http://www.kforum-tech.com/general/engine-not-running-troubleshooting-chart.pdf

Also the search box on portal page is very useful..just type in the subject e.g bike wont start/checking sparkplugs/and technical page.

I am by no means mechanically competent, but being a part of this forum has helped me solve a lot of little issues, become more familiar with my bike, and have more confidence pulling things apart. I do have a bad habit of breaking something else when I am fixing something  

Everything that can go wrong with a K bike has been well and truly covered in the forum. There are many wiser heads than me on this forum, who have always been willing to help me.

Speedometer sensor may just need a clean. It is located near final drive oil filler cap. Undo hex head bolt, prise out gently (gently...I just broke one getting it out) and wipe down, reinstall.

Keep going, as you said, worse case is in the trailer and off to the mechanic.

Cheers,

Mick

Here is the Chris Harris video I mentioned, putting oil in the cylinders. His channel can teach you a lot about BMW bikes, and maybe expand your vocabulary too.

https://www.youtube.com/watch?v=DerHlx-bO0s

Mick67 wrote:
Fuel - clean fuel, fuel pump - connector/fuse, recirculating in tank,fuel at rail, fuel at injectors

I am going to try and get this done next. Need to find good examples of how to do all this though. Seems most videos that are circulating are for the K-75 which has the same basic mechanics as mine - am i correct in this?

Michael Sydney wrote:Here is the Chris Harris video I mentioned, putting oil in the cylinders. His channel can teach you a lot about BMW bikes, and maybe expand your vocabulary too.

https://www.youtube.com/watch?v=DerHlx-bO0s

Thanks! Excellent video(s).

Quick update. Based on the video posted from Chris Harris, I thought maybe I had not sprayed enough fogging oil into the pistons. So I removed them, sprayed a bit more and it just about started, it actually burned out some of the oil and sounded like it was going to go, but then didn't. It's back to the same spot. So, should I try getting new plugs now and spraying it again to see if gets pressure? It was so close to firing up, I did it all a 3rd time, spraying even more and it sounded even close to going. I guess it is something to do with loss of pressure after all.

Thoughts?

Check that your plug electrodes have the correct gap—from 0.6mm to less than 0.9mm—and that the plug wires are on the correct plugs from the coils. Oil it up and do it again. The smoke will repel midges.

Do the plugs have the correct terminal?  If all you have is the threaded stud at the top that can drastically reduce spark efficiency.  The plug wires are designed to work with the large tips on the Bosch plugs.  NGK doesn't come with these "terminal nuts".  you have to get them from a small engine shop where they may have old spark plugs you can take them off of.