Had another "interesting" moment the other day. Living here in the Sunshine State, I've been slogging through mug and driving rain to get to the car every day for the past couple of weeks, and taking any chance I can get to ride.

Finally had a chance on Monday - bike started well, ran beautifully ... until about half way to work, when it started grumbling at idle, revving with reluctance and not pulling very well. The first hesitation cleared, but it wasn't entirely right. With care and attention and not riding in the right-hand lane too much, I got to work fine, until I pulled up at the entrance to the parking garage and it stalled. Luckily, I was on a downhill slope onto the flat and could push or paddle from there. Even more luckily, it started again and ran reluctantly as I pulled into a parking spot - and then stalled again.

First thought: It had to sit in driving rain for a day before I could get a over over it, so water got in somewhere. Fuel? Electrical contacts?

Second thought: At the last full tank, I put a bottle of strong injector cleaner in there. Did that shift enough gunk to clog something? Yes, it has a good fuel filter, but that's not the entire system, is it?

Came out of work (after midnight) - wouldn't start, but was turning over vigorously and the pump was audible.

Check there's pressure in the fuel lines - yes. Check there's spark at the leads - yes. Check the tank with a torch - no visible water bubbles or layers. Check and secure the electrical connections to both computers - both good. Take taxi home.

Drove in with extra tools the next day. Fuel system is holding about the right pressure, so it's not another F#@%^&$ing FPR. Resistances on both coils are okay.

Pull injector rail, hold over piece of cardboard - oh, what sad little barely-there damp spots!

So, I bought the rail with the four injectors home, and the tank as well so I could empty and clean it.

Before ringing around for injector servicing services, I checked resistances on the four injectors:

#1 - 18 ohm. Hmmm, not perfect but it's old, should be fine.
#2 - 18 ohm.
#3 - Doesn't want to play. Maybe a flicker ... Nah, get stuffed.
#4 - 18 ohm. No! 23 ohm. No! 242 ohm. No! 19 ohm. No! No current at all. No! 18 ohm.

So I've got four new injectors in the mail, while I work on checking everything else I can.

Certainly sounds like it, maybe show them an axe and see if they have a change of heart.

points file and clean up ?

we have had a bit of the wet stuff round here just recently ....are they green in colour yet ? lol

deoxit is your friend

[quote="Jhepburn"]Had another "interesting" moment the other day. Living here in the Sunshine State, I've been slogging through mug and driving rain to get to the car every day for the past couple of weeks, and taking any chance I can get to ride.

Finally had a chance on Monday - bike started well, ran beautifully ... until about half way to work, when it started grumbling at idle, revving with reluctance and not pulling very well. The first hesitation cleared, but it wasn't entirely right. With care and attention and not riding in the right-hand lane too much, I got to work fine, until I pulled up at the entrance to the parking garage and it stalled. Luckily, I was on a downhill slope onto the flat and could push or paddle from there. Even more luckily, it started again and ran reluctantly as I pulled into a parking spot - and then stalled again.

First thought: It had to sit in driving rain for a day before I could get a over over it, so water got in somewhere. Fuel? Electrical contacts?

Second thought: At the last full tank, I put a bottle of strong injector cleaner in there. Did that shift enough gunk to clog something? Yes, it has a good fuel filter, but that's not the entire system, is it?

Came out of work (after midnight) - wouldn't start, but was turning over vigorously and the pump was audible.

Check there's pressure in the fuel lines - yes. Check there's spark at the leads - yes. Check the tank with a torch - no visible water bubbles or layers. Check and secure the electrical connections to both computers - both good. Take taxi home.

Drove in with extra tools the next day. Fuel system is holding about the right pressure, so it's not another F#@%^&$ing FPR. Resistances on both coils are okay.

Pull injector rail, hold over piece of cardboard - oh, what sad little barely-there damp spots!

So, I bought the rail with the four injectors home, and the tank as well so I could empty and clean it.

Before ringing around for injector servicing services, I checked resistances on the four injectors:

#1 - 18 ohm. Hmmm, not perfect but it's old, should be fine.
#2 - 18 ohm.
#3 - Doesn't want to play. Maybe a flicker ... Nah, get stuffed.
#4 - 18 ohm. No! 23 ohm. No! 242 ohm. No! 19 ohm. No! No current at all. No! 18 ohm.

So I've got four new injectors in the mail, while I work on checking everything else I can.[/quote] I am curious where you sourced injectors from. I gave the local Bosch service center the Bosch part number and they claimed there are no such injectors available in North America. BMW wants a small fortune for them.

The ford windsor V8 used in the 90s mustangs have the same injectors so ask for those, it might work sometimes the part number varies as a change in plastic color will change the number.

There's a lot of discussion online about alternate injectors. Clearly, this is a commodity area where off-the-shelf is handier for a manufacturer of vehicles, and injector manufacturers like Bosch would get sick of everyone needing a different specification, and would try and make as few different types as possible.

In fact, the K100 injectors were shared with the four-cylinder 318i sedan of the same era (which, funnily enough, I almost bought last year - matching pair!)

Anyway: Bookmark this: http://www.ibmwr.org/otech/partsubs.shtml

There are injectors listed there. Basically - several hundred models of Ford, principally the six-cylinder ones but apparently also at least one V8, used the same type. This is handy. You can get them off eBay for about $38 and well-regarded, but I needed something more local for faster delivery.

For Australians, try this: http://www.injectorsonline.com/index.php Very cheap. Basic website, so you have to know what you're after, but I went into Standard Injectors and got mid-nineties Ford ones for $60 each. The 318i ones are $75 or $65, and I have no idea what the difference is, but the Ford ones fit and the bike has now started, idled and reved happily. I have to pick it up later today or tomorrow. If you're picking injectors, go on the image - hover over the icon and you'll soon see that there are very few different types, so get one that matches the right image. I ordered at 1am after work, I got an email in the morning saying they'd be in a courier bag later that day, and they were delivered the next morning.

Oh, and: Munich Motorcycles were asking $225 each, I believe.

Good site to know must book mark it. I have been trying to find some of the 4 hole injectors as they seem to give better performance.

The only autos that use the same injectors as a K100 with two valves per cylinder are the Renault Fuego with the 1600 cc in line four, and according to some sources the AMC Alliance with the same engine. I have used a Borg Warner replacement injector that Borg Warner claims is a direct replacement but the bike does not run the same with the Borg Warners as it does with OEM Bosch injectors.

I'm running a set from a BMW 323, 1984? Probably the same as some of the 4 cylinder models. I did some research on injectors last year but filed the info away......... somewhere in a safe place
Got them for nothing as most of the boy racers running those Beemers fit bigger injectors.

...fitted some new injectors today from a 95 hyundai excel SOHC 1500cc and they go great , they were easy to fit with the new o rings from Motorworks or motobins cannot remember but at any rate tuned the TB's to 22 increments of mercury each , steady and the response is sharp.....was trying to get rid of the 3000rpm resonance shall find out when next cruise....but initially I am happy with the sound and response..apparently same flow and impedence as the OEM Bosch.

Well, I'm happy! Finally able to pick up Hermann the RS.

After a couple of days sitting idle - started almost immediately (after priming the fuel pump) with no idle adjust - it's been a while since that was possible. Ram smoothly and strongly and then, after stopping for petrol, started again not just instantly but with an angry-tiger roar.

Continued running well, pulled from low revs smoothly and from high revs eagerly, idled on the upper side of intended, instead of the erratic lower side ...

Everything good, in other words.

I can't wait to see what effect this has on fuel economy - I expect there to be some change, but I'm not sure in which direction.

I should now probably change the spark plugs, since at least two of them have been running with imperfect injectors for a while.

Great news. Your fuel consumption will only increase I'm tipping, as you get more confident and twist that throttle.

Update on Hyundai injectors....idle great, fitted fuel pressure gauge and noticed bleed down of pressure overnight so a little harder to start than usual but not a problem when warmed up....took her for a high speed test and response very good through to 8500...but there was a difference in that the ZORST noise was now very throaty and noticeable very loud burble when decelerating which seemed a little unbecoming for a beemer.....got back , shut down and watched the injectors bleed down.....
Decided to refit the OEM bosch injectors which took about 5 minutes now getting good at this....started first kick ran fine, still had the resonance ( still had with the Hyundai injectors too) so changed the temp sensor behind radiator....what a shitty plug to undo when you remove the bare minimum...anyhow no change....
what have I ascertained from all this?...my original injectors are healthier than the second hand hyundai units which do work but appear to be a little rich and the 3000 rpm resonance I have needs further investigation...can I borrow a computer from someone nearby...for about 5 minutes...
anyhow lovely day for a ride and lunch with my daughter...

Jhepburn wrote:Well, I'm happy! Finally able to pick up Hermann the RS.

After a couple of days sitting idle - started almost immediately (after priming the fuel pump) with no idle adjust - it's been a while since that was possible. Ram smoothly and strongly and then, after stopping for petrol, started again not just instantly but with an angry-tiger roar.

Continued running well, pulled from low revs smoothly and from high revs eagerly, idled on the upper side of intended, instead of the erratic lower side ...

Everything good, in other words.

I can't wait to see what effect this has on fuel economy - I expect there to be some change, but I'm not sure in which direction.

I should now probably change the spark plugs, since at least two of them have been running with imperfect injectors for a while.

a good idea jh ...new sparkies is just good maintenance ...

Nice to see she takes after her dad in the looks stakes.

I bet you can't tell who is who.
Except for the wrinkles.

laughter lines pal....from all the funny people on this forum....

And one of em has their own teeth.
Ah Windsor, nice spot.

we all have our own teeth...no borrowed teeth here...all paid for.