Stalling and stuttering + hard to start

[ndanielli]

I originally thought that I had a battery issue, but it has load tested fine and seems to be working ok.
Several times in the past week I have had my 1987 R80 hiccup and stall,
gen light on, while riding at cruising speed. A couple of times it kicked back in within a
second or so and I was able to keep riding, the other times I coasted to the side of
the road, waited a minute and started it up, backfired, and was able to ride off. I am also
experiencing starting problems after work on my way home. The starter is spinning but the engine
just does not catch. Eventually (10 tries?) it catches (so far!) and off I go...

My current theory is some sort of fuel/air issue. Plugged gas cap? Vapor lock? It has been rainy
as heck here lately and these have happened on rainy days, but that may
be a distraction. Any advice would be GREATLY appreciated. This is currently my sole
commuter vehicle for a 75 mile round trip.

Thanks!
Neer

[Braddog]

Let's face it, you need 3 things for an engine to run...fuel, spark, and compression.

My RS has had similar issues, and worse yet, it's been quite sporadic. Bike will run absolutely great for a few hundred miles, then start stalling at the most inopportune times.

It's not my battery, either.

I checked spark, it seems I have a good blue "flame".

That leaves...fuel. I checked the flow from the tank, it's clean and plentiful. When my bike has stalled, it's almost always started right up again. When it stalls, it is as if it's running out of gas.

Could the floats be sticking? Wouldn't both floats have to stick simultaneously for the bike to quit running?

Didn't mean to hijack this thread, just thought I'd "pile on".

I'll hang up and listen now.
:lurk

[PMonk]

Pop off the float bowls and see if you collected any water and check to see if you have good flow through your filters?

[nealart]

Have your coils tested.

You can look at them to see if there are cracks.

Also the plug wires themselves can be bad and cause problems in the rain.

[20774]

Check the heat sink paste on the ignition module...

[nealart]

Bikes not starting in the rain reminds me of this terrible joke.

Don't click it if you are offended by filthy humor:

http://www.michaelclark.name/jokes/menwomen/vaseline.shtml

[JETHRIDGE]

OK, Guys. Try This. Remove the tank and Clean every Electrical conection you can unplug. Shoot electrical cleaner in the ones you can't unplug. Pull the fuses and clean the ends. Doing this solved the somewhat same problem you are having. My 83 R100Rt would quit as if the kill switch had been activated, and then would jump start and run fine until the next time.May not solve the problem but could prevent a problem latter on.

[tommcgee]

Have your coils tested.

You can look at them to see if there are cracks.


Look at them at night. Sometimes coil cracks aren't visually obvious, but you'll see the breech at night.

[rocketman]

OK, Guys. Try This. Remove the tank and Clean every Electrical conection you can unplug. Shoot electrical cleaner in the ones you can't unplug. Pull the fuses and clean the ends. Doing this solved the somewhat same problem you are having. My 83 R100Rt would quit as if the kill switch had been activated, and then would jump start and run fine until the next time.May not solve the problem but could prevent a problem latter on.

Thats what I'm thinking as well intermittent short somewhere that causes loss of electrical connections needed to maintain spark, not uncommon with a 30 year old machine.

RM

[mbrickell]

FWIW, this is exactly how my last 2 Volkswagens acted when they have a bad ignition coil. There was a hairline crack in both, you could see arc at night if you looked closely. 2 new coils on both cars, no issues. Seeing that some have recommended you look at coils on your bike, I second the idea. In large part, an engine is an engine, car or bike.

[beemerguru]

When you find out there's no water in the gas, all the electrical connnections are cleaned, the coils check out, and you've replaced the spark plug wires; if you still have the problem, swap out the ignition canister - same symptoms as a failing bean can.

[gerardjs]

Have you checked your valve clearances lately? You're piling up miles in the summer heat. Maybe an exhaust valve being held open?

[grumpyone]

Neer Im betting on water in the gas; BUT your bike is after the emission curse so you might be having a problem with the fuel shut offs ans such under the tank in the starter cover if they have not been removed. If they are there I would remove them they seem to run better and have less places for problems to occur.
Good Luck
Jim and Esther

[ndanielli]

Thanks, guys! I am working through the list now.Of course, it has been running great
the last couple of dry days, but something is definitely up and I'm staying on it, since
this is currently my main vehicle.

Thanks Again,
Neer

[co_g30]

Have your coils tested.

You can look at them to see if there are cracks.

Also the plug wires themselves can be bad and cause problems in the rain.

----

I had similar symptoms on my own 87 R80, ended up being the coil, cracks all over that looked like scratches on the casing and which fooled me for a bit.

more details here: link (http://redlegsrides.blogspot.com/2008/07/joys-of-problem-diagnosis-on-airhead.html)

note, along with the updated coil, changed out the ICM as well, see bottom of link above.

hth

[ndanielli]

Update: I checked and adjusted valve clearances and cleaned up my carbs as
much as possible without taking them off the bike. It is running great and I thought
the problem was licked, but right at the begining of a short test ride tonight it
koncked out after about 20 yards, gen light on, engine dead. I pulled over and started up just fine, then 30 yards later it sputtered, then lurched and then ran like a top for the next half hour. So, my next guesses are:

Coil - It's the new model and is fairly new in terms of mileage but a couple of years old (garaged by PO).

Wiring harness - I will search for any shorts

Hall effect sensor - This seems to be a common problem on the K-Bikes. Does it
make sense here? If so, can I buy a whole new bean can or must I dremel the
sensor out and rivet a new one in?


Any other guesses?

Thanks!
Neer

[beemerguru]

All the symptoms of a failing can. After a while, it will just stop..maybe backfire first..but just stop and never start again.

Cheap first try is check out the spark plug wires..especially if you still have the metal cap OEM version. Move them around while you test each one to check for a short. But spark plug wires would both have to go at the same time in order for both cylinders to stop...so can that idea.

If after all the other test you still find nothing, call Rick at Motorad Electric. He sells rebuilt cans or he can rebuild yours - but it takes a while.

Or hit the IBMWR.org marketplace or eBay and see if one is for sale..or if there's a local airhead who has a spare sitting on the shelf.

I have a rebuilt one on the shelf you can use until you decide what to do. Takes about a half hour to replace..and then have a timing light to set the timing.

[beemerguru]

Neer,

The can is held on by 2 small bolts and a plastic socket.

Disconnect the ground, remove the front cover, make a mark to position the top left "arm" that holds the can in place, follow the little black wire to the orange plastic socket, cut tie wrap if there, take a REALLY small screwdriver or sharp edge instrument and release the wire bail, unplug the wire, put the wire bail BACK in it's proper position, remover the 2 bolts and slide the old can off, install the new can (you did replace the O ring right?), (and lightly oiled it too), do a best guestamate of lining up the cam slot to the can (it's offset), slide it in while gently wiggling it until it fully seats, align the top left arm with the mark you made, put bolts back in but not too tight, slide the wire back up and plug it into the socket, (the wire bail will catch it), tie wrap it back up, hook up ground wire, attach timing light, start engine, warm it up a little until it settles into a smooth idle, aim light a the little hole above the left carb (it helps to remove the little black rubber thingy), and hope the S is sitting right in the middle of the hole.

If not, reach around without burning yourself on the header and slowly turn the can until the S is in the middle. Put timing light down, turn off engine and reach around and tighten bolts. Start engine and see if S is still in the middle,,then run the engine up to 2-3K and see is the Z or F is in the middle (full advance) UNLESS you have dual plugged heads, then the Z or F must be set for the BOTTOM of the hole.

After that, turn engine off, disconnect ground, put front cover back on, connect ground, put tool away, and go for a ride.

[jforgo]

your ignition switch. It can have intermittent, transient connections to cause these symptoms. With bike running (preferably) ever so slightly rotate key - only by a degree or 3 at a time. Also try pressing on key/lock cylinder while running and see what happens.
This all simulates vibrations to a worn ignition lock/cylinder.
I had bean can/coil worries as well, and this "mechanical" test of the electrical ignition switch surfaced the true culprit for me.

[nealart]

I didn't notice the gen light before.

You should check that the diode board is grounded well.

[ebeeby]

Are you sure the battery is good? Did you test it with a VOM or a load tester? A bad cell can show good voltage on a VOM but show bad under load. Can you borrow a battery to test with?

Don't ask me (or the towing company) how I know about flaky batteries.

[DennisDarrow]

It would seem to me that the ignition switch or a bad connection in the ignition system is your culprit. Typically, if your battery/charging system is strong enough to start the machine, it will continue to run despite charging faults.

Sorry Bud.....but it will get straightened out....just persist and when you have that whaalaaaa moment it will feel so very good.................Ride.........Dennis

[MotorradMike]

A friend of mine has an R90S. It had this problem in the rain only.

He found a pinched wire under the engine cover which was allowing water into the points area.

Quick to check anyway.

Mike

[ndanielli]

Let me dig more. The ignition switch! For the past couple of weeks I have been using
the spare keys for my bike since the originals have been locked in my wife's car.
There is definitely more "wiggle" in the switch with the spare/copy than the original.
I will switch back to the factory key and see if this all goes away. It fits the time line...
If so, I will feel like a moron.

Neer

[ndanielli]

Are you sure the battery is good? Did you test it with a VOM or a load tester? A bad cell can show good voltage on a VOM but show bad under load. Can you borrow a battery to test with?

Don't ask me (or the towing company) how I know about flaky batteries.

That was my first test, first with a meter and then a load test at the parts store. Both
passed, though the electrolyte is a touch weak.

Thanks,
Neer

[beemerguru]

A friend of mine has an R90S. It had this problem in the rain only.

He found a pinched wire under the engine cover which was allowing water into the points area.

Quick to check anyway.

Mike

No points in an '87. Electronic ignition...although he could have caught the wire from the can between the cover and case...but that would give a continous failure, not intermittent.

[ndanielli]

Just an update, I am still digging. I am 99% sure that it is not the ignition switch itself.
I can move it around a bit and it won't cause the issue. I had the issue happen the
other day, just after starting (3 minutes) as usual, and it went right away. Also,
today I had a terrible time starting the bike to head to work. I would hit the starter and
get the "wee wee wee" but it would not catch. It took about 10 tries over five
minutes before it finally caught. Does this sound like a failing beancan? Is there
anything I can test, short of replacing the ignition and seeing if the issue goes
away? I love the bike but, ugh, another $180 to rebuild the can! :banghead

[20774]

Also, today I had a terrible time starting the bike to head to work. I would hit the starter and get the "wee wee wee" but it would not catch.

When it's doing this, try pulling the plugs, reinserting into the spark plug caps, lay the plug threads down against the fins, and hit the starter. Do this in somewhat of a dark place if you can so you can a) see if you have spark and 2) see what type of spark it is. I've heard (but never experienced myself) that a plug might not fire under compression but will work outside the cylinder, so this test might not be conclusive...but if you have no spark, that tells you something. A weak spark is is yellow and a strong spark is bluish.

[pswanson]

If you pull your plug, or use an extra, grounded against a fin (to check for spark), from what I've heard looking into the same symptoms on my '89 -- make sure you ALWAYS have it grounded. Letting it turn over with the plug completely in the open apparently will fry your can, coil or ICM if not already buggered. I was doing that to see if one cylinder was running worse than the other, and I'm wondering if I created a bigger problem also. Hope it helps,

Paul

[108625]

A word of warning:
If you pull your plug to perform the spark test, make sure you've shut off the fuel and drained your float bowls...Or you could have an external combustion engine.

Bob

[1_mtn_hiker]

I'm reading three issues here:
1) wet weather stalling --> coil? like others have posted
2) start/restart issues --> starter motor / relay
3) stalling after 3 minutes of run time --> my current interest area

I just replaced my 89 R100's Valeo starter motor with a ND unit from Motorrad Elektrik. That resolved my no-start issue. It was giving me clues for awhile, like ten times to start, probably as the magnets were giving way. Then it just would not start. I'm replacing the relay just to be current and matched.

I am interested if you ever traced down why stalling after 3 minutes. I had that today. My cold idle perhaps, because then after bike was apparently warm, it ran great.