*3 LS doe not like the rain

[oldbiker]

Hello
My 83 R 65 LS does not like heavy rain. In heavy rain plenty of which we are getting this "summer" the engine practically stalls and is a nuisance in town traffic. If I stop for a few minutes with the engine idling badly it will dry and run smooth for a while again. I dis notice that the speedo cable is a vector for water to get into the gearbox. The suggestion of enclosing it in cable conduit is a good solution- thanks to rs mike.  Any suggestions as to where the rain is causing my stalling.
I have finally managed to atttach a photo of my bike.

[Bob_Roller]

Check your ignition coil, if it is black and gray in color, replace it .

It's got a reputation for the case cracking and causing problems when your in wet conditions .

From the picture, this doesn't seem to be your case, but the original ignition wires had metal caps at the plugs, so if by chance yours still have the metal caps, they may very well be the originals .

Water getting into the transmission is caused by the rubber boot that goes over the speedometer cable at the transmission .

It oses it's grip on the cable and allows water into the transmission, not a bad idea to replace the boot every few years .

Some have suggested putting a rubber sealant at the top of the boot after it is installed, to help prevent water intrusion .

[montmil]

Do you still have the gray and black, OEM Bosch ignition coil? Often referred to as the Crack-O-Matic due to it's propensity to develop hairline cracks that drastically alter coil performance on damp days.

Yank the tank and have a look.

Monte

[nhmaf]

+1 what Monte and Bos said about the coil, and also about the plug wires&caps - if old/cracked or the metal cap variety they can let in water and spoil your day.

I also usually put a fingertip-sized gob of heavy grease UNDER the rubber boot before I slide it on down to its place on the transmission housing - that way, even if some water trickles down the cable past the boot, it still has to get through the gob of grease to get into the transmission - probably overkill.

that is a very pretty blue LS you have!

[Red_Hen]

Agree with the group.

Read a post today on BMW MOA Airhead section about a guy with an Airhead dying in the rain - turned out to be a cracked coil.

[bruce_launceston]

I agree, most likely the coil. Also I have my ignition leads curving back towards the carbs then forward to the plug cap so that any rainwater they collect as you ride along will shed off and less will run down onto the plug caps.

[oldbiker]

Thanks boys for the swift replies. I removed the tank this evening. It is getting dark earlier now by the day. The has a longer travel  coil is black indeed but I reckon it is not original as "made in Japan " is stamped on it. The plug leads seem to be an integral part of the coil.The right plug lead is long enough to curve to the carb and back as suggested by Bruce. The left lead has a longer travel due to the coil being offset on the frame and cannot follow the same curve as the right. I notice now that it has an extra sheath over the lead. I did not notice any cracks on the coil but maybe I should use soldered joiners on those taped up connections.

[nhmaf]

Hmmm, I'm not familiar with the look of that coil at all - possibly it is still part of the problem?

[Bob_Roller]

I'm still going to go on a limb and say that if the bikes gives you problems in wet conditions, it's most likely an ignition problem, most likely the secondary high voltage side .

[Teo]

That coil and plug lead setup looks like a Japanese aftermarket rig.  My little '73 Honda 175 had a coil and plug wire set up like that.  It is indeed one piece.  Makes it har to ohm the wires and plug caps.  Running crappy in the rain or wet does indeed sound like a cracked coil or bad plug wire insulation/bad plug cap.

As to the speedo cable boot, use a small nylon zip tie around the "neck" to keep it watertight or put shrink tube over the top to seal it.  At any rate, never direct water at that area and check your transmission oil about every three months to see if any water has gotten in.

Teo

[Rob Valdez 79 R65]

I recommend a Dyna Brown coil from Motorrad Elecktrik: http://www.motoelekt.com/ignition.htm

He also has ignition wires with NGK caps.  They are good and waterproof.

I typically recommend getting wires & caps from MikesXS supply, as they are less expensive, but they don't come with the High Tension lead ends; and the tips he does sell are not as nice as the ones that came on our original wires.  The BMW ones are soldered on, and can be removed and reused indefinitely.
Oops, I just saw you are in Ireland.  MikesXS in the U.S. does not ship there, but Heiden Tuning is the same thing in the Netherlands - http://www.xs650.biz/p/36/2684/mo74-cgp2|23=1

Or you can source a pair of used OEM wires from a breaker, just for the tips, and get your wires and caps from Heiden - € 4,00 for the wires, € 6,00 for the caps.  
You can probably get NGK caps (5K ohm, I believe you want) from your local bike shop, too.
If you get your wire locally, just make sure it is high-quality solid copper core.

That is junk that you have on your bike, I'm afraid.  Someone just used whatever they had at hand.
You can't go wrong with Motorrad Elektrik.  Rick is a great guy to do business with and can answer any questions you might have about his products.

His LED tail light inserts are the cat's meow, too.  Check out his entire site.

[Barry]

I typically recommend getting wires & caps from MikesXS supply

That's a great supplier with a very good range of low cost Ignition coils some of which could be used by airheads. They also stock something I've never seen anywhere else - 1Kohm NGK spark plug caps for points ignition.

Wish they were in the UK.

[Rob Valdez 79 R65]

I typically recommend getting wires & caps from MikesXS supply

That's a great supplier with a very good range of low cost Ignition coils some of which could be used by airheads. They also stock something I've never seen anywhere else - 1Kohm NGK spark plug caps for points ignition.

Wish they were in the UK.

I would contact the Netherlands store to see if they can get them.
NGK is pretty big worldwide - surely they are available somewhere.
But I've been using the 5K on my points ignition for a LONG time and have never had an issue.

[oldbiker]

Thanks for the help. I am presently organising to get the brown Dyna coil and the leads from Netherlands. Strangely enough the bike is running well except in extremely wet conditions. Will post when I receive the nnew .

[Dizerens5]

My points 79 has two coils supposedly BMW but marked made in Brazil. they work fine though.