fuel injection problems

[guzzirider]

I have an '85 rt with 66000 miles and I having problems with engine flooding while try to start.My father had his friend check the jetron fuel brain and found a problem with a heat sink. My dad placed the brain off his 86 rs on to my bike and it starts runs fine.Anybody else have a problem with this?

[HFbmw]

Doesn't sound cheap! I have had problems in the winter time due to forgetting to dorp the 20W50 oil. Then the bike would flood and time to replace the spark plugs.

tim lindstrom
91 k100lt

[1der]

Just took over my dad's K1100 with 108,000mi. Have been riding his R80 with 160,000mi. Not familiar with the K. Question, are the injectors in the "K" like a car, in as much that you would use a injector cleaning additive? We call the "R80",Brutus. The "K", I'm calling the "Beast". Also what grade gas do you run in the "K"?
1der

[BlackHoof]

I'm running the mid-grade 89 rated octane BP gas in my K1100. I've never
heard it ping on the 87 grade, but don't think it needs the ethanol free 91,
so I split the difference & put in the 89. Others may have more experience,
I've only owned my K since last fall. :dance

[GregFeeler]

Just took over my dad's K1100 with 108,000mi. Have been riding his R80 with 160,000mi. Not familiar with the K. Question, are the injectors in the "K" like a car, in as much that you would use a injector cleaning additive? We call the "R80",Brutus. The "K", I'm calling the "Beast". Also what grade gas do you run in the "K"?
1der

In my experience, Techron from Chevron is an exceptional product. I run Chevron gas when I can, but I always run at least one tank dosed with Techron concentrate before every oil change and have never had injector problems on a whole series of cars and bikes with fuel injection.

As for fuel grade, run what doesn't ping. Some K-bikes have had the timing advanced over stock for additional performance, in which case you need to run premium.

[1der]

Took a small ride tonight with my son. (110mi) filled the tank with 89 octane. Ran great. Strange to have son riding the R80, and me the "K" Oh well, what goes around, is coming back around. Use to be MY dad on the "K", and me on the R80.
MY dad went to see his girlfriend in Harrisburg PA. Had one small problem that maybe someone can shed some light on. After riding 30 miles and then getting gas, after several miles the light below the high beam (generator light I think) flickered once or twice then quit. Didn't do it again. Dose anyone know what happened? Bike hasen't been ridden in over a year?
1der

[HFbmw]

howdy,
If the beemer has not seen the light of road for a year then the battery needed a bump from the alternator. The light is part of the charging system.
Some of these older beemers will have that red light sending out a glimmer or glow.
I remember being at the Franklin, Ne rally. An old airhead didn't have or wasn't charging. So the rally gurus surounded the beemer, head scratchin and low tones of voices until one got excited.
All the bike needed was a new bulb in the generator light socket. So they took the bulb from the neutral socket and the Air head was ready for the ride back to home and maybe a bmw dealer...

Now remember these are german bikes... made by german engineers who might have different ideas than... brand X....

tim lindstrom
91 k100lt, 134,000 miles

[deilenberger]

I have an '85 rt with 66000 miles and I having problems with engine flooding while try to start.My father had his friend check the jetron fuel brain and found a problem with a heat sink. My dad placed the brain off his 86 rs on to my bike and it starts runs fine.Anybody else have a problem with this?I think all the posts have sort of lost track of the OP's problem.

He has a bad Jetronic brain on his '85 K bike.

My suggestion - replace it. This is probably the first failed one I've ever heard of - which means there are literally thousands of these things sitting on shelves from wrecked K bikes that are never going to be needed. Since your dad's 86 brain worked fine with it (and AFAIK - there was NO change ever to the 2-valve K100 brain) - that opens the range of years you can look for.

I'd be watching the IBMWR marketplace for K100's being parted out, Ebay, the MOA Fleamarket (on-line and in the Owners News).. and simply find one and replace it.. then RIDE ON..

[guzzirider]

I've found a brain from a fellow on the ibmw riders page.My father says that is a guy that can maybe repair these things.I'll install the new one and see if this gentelman can indeed fix my old one.I'll post my findings along with some info on how we found this problem.

[deilenberger]

I've found a brain from a fellow on the ibmw riders page.My father says that is a guy that can maybe repair these things.I'll install the new one and see if this gentelman can indeed fix my old one.I'll post my findings along with some info on how we found this problem.There may well be someone who can repair these (there are for cars) - but with it having a failure rate of 1:50,000 (yours vs all the K-2 valve bikes ever built) it wouldn't seem economically sound to bother doing it. Undoubtably the rebuild would cost more than a good used one if you wanted a spare (I think I gave the spare I had away a long time ago..) They really don't go bad. I suspect your bike must have been hit by lightning or something :D

[guzzirider]

Well I got a brain from a guy over on IBMWR ,and installed it.The good news is the the bike starts and runs,the bad news is it idles very rough.The bike runs down the road very well ,but almost dies at stops.A car mechanic friend says possible injector problem.He told to take a infared temperture gun ,the that HVAC techs use on a/c's and check the temp on each exhaust header.They ought to be with in 20-30 degrees of each other.Well I checked each header right where the exhaust bolts up,and no.1 was 710 degrees, no.2 and 3 were 650 and no. 4 was 460 degrees.According to the temps, no. 1 was lean and no. 4 was rich.I got 2 borg/warner injectors from a local parts house and installed them today.The bike starts well and idles very smooth now.I am going the send off my two injectors to be rebuilt and swap them in for the other 2 injectors.My father started using an infared temperture gun to help set air/fuel mixture on all the bikes he works on and it works very well.

[deilenberger]

Interesting use of the IR temperture gun.. I like it :)

I suspect the bad injectors may remain bad.. if it was me - I'd either send all 4 out for cleaning, or put 4 new ones in. The actual results on "rebuilding" (which only means they replace a plastic cap on it and some O rings - and clean it by reverse flushing it) are mixed - especially if the bike had been sitting with stale fuel in it.