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Bike Sat in the Rain for 2 days and Now Won't Start
- Thread starter Bssoap74
- Start date
A friend of mine don't like to cover his bike and after a few years it has gone all rusty as well as mold growing on the rubber bits!Charles
XS400 Addict
Like I said...what about when I go to work? Actually, today, went to lunch, took a few tries to crank her over. When she started...running on one cylinder only. Hadn't rained since I parked this morning, but there's a lot of moisture in the air and very overcast. I doubt a cover would have made any difference in this case.
spray everthing with wd40 or gt whatever, might be the HT leads breaking down or a weak battery.
I road for 11 hours in torrential rain a few years again and it never missed a beat!
( yes my boots had a lake in them and I wore a black bin bag under my motorcycle gear, but that's another story)
I road for 11 hours in torrential rain a few years again and it never missed a beat!
( yes my boots had a lake in them and I wore a black bin bag under my motorcycle gear, but that's another story)
Some bikes have their critical parts covered/protected better than others. As a general rule you want to protect your bike from the rain if you can, but of course exposures will happen sometimes. The biggest problems and expenses I've had with my rebuild have been 100% due to careless POs that left the bike outside in the rain.
Some of your gaskets/seals/covers/etc may not be so tight fitting after 30-some-odd years so water gets into places where it shouldn't.
Some of your gaskets/seals/covers/etc may not be so tight fitting after 30-some-odd years so water gets into places where it shouldn't.
lhaolpa
XS400 Junkie
Make sure that the cover doesn't go to the ground,or you'll get a lot of rust as the moisture will have nowhere to go,and the moisture in the ground will come up when it gets warmer in the daytime. All you really need to cover is the top to keep rain from getting into places where it will cause you problems.You can spray with WD-40 or something to disperse water. lha
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Charles
XS400 Addict
Keep bumping this. 
So, I was thinking last night. When it's been raining or wet outside the right cylinder only seems to spark at idle, and even then, intermittently. If I rev it above idle, no spark at all. After the bike's been running for a while, the right cylinder clears up and runs fine. So, given that it seems to be only on the right, I'm thinking the coil might be weak? Maybe it's fine at idle, but when you rev it, putting more demand on the coil (does it even work that way?), it cuts out cause it can't keep up and overcome the moisture that's in it?? Does that sound plausible? I guess I can spray some water on it, then register the voltage/ohms.
So, I was thinking last night. When it's been raining or wet outside the right cylinder only seems to spark at idle, and even then, intermittently. If I rev it above idle, no spark at all. After the bike's been running for a while, the right cylinder clears up and runs fine. So, given that it seems to be only on the right, I'm thinking the coil might be weak? Maybe it's fine at idle, but when you rev it, putting more demand on the coil (does it even work that way?), it cuts out cause it can't keep up and overcome the moisture that's in it?? Does that sound plausible? I guess I can spray some water on it, then register the voltage/ohms.
I don't think there is more "demand" on the coil at higher rpms. It probably fires with the same "strength" at all rpms; it just fires more frequently at higher rpms.
I would start with the more obvious solution first. The right side is the side more exposed to rain when the bike is on its side stand. The coil itself is protected by the tank, but the spark plug wire is not. The spark plug cable may not be water-tight anymore. I'd suspect that water is getting between the connection made with the spark plug.
I can't say I would recommend spraying water on any electronic parts intentionally.
I would start with the more obvious solution first. The right side is the side more exposed to rain when the bike is on its side stand. The coil itself is protected by the tank, but the spark plug wire is not. The spark plug cable may not be water-tight anymore. I'd suspect that water is getting between the connection made with the spark plug.
I can't say I would recommend spraying water on any electronic parts intentionally.
brownv1
XS400 Enthusiast
BC seems to know his stuff. That being said my expertise is not bike's it's aircraft. There are soooooo many variable's in getting the engine to run smooth. We use mag's not plugs so there is a bit of diff there. If I were you trade out the coils and try to replicate. That will eliminate or confirm the coil. Firing happens faster at higher RPM's sooo it COULD be a wet coil. THAT being said I doub't they are getting wet unless you were riding in the rain it's probably a bad coil or connection.
Kinda Tipsy feel free to debate...will expand my knowledge
Kinda Tipsy feel free to debate...will expand my knowledge
ThePsuedoMonkey
XS400 Addict
Like Drewpy, I've not had problems riding in rainy weather on mine. I have also left her in rain while at work (due to necessity) for about 10 hours, and even then she started up without much additional effort (three kicks instead of 1-2). I don't know if you've replaced anything in the ignition system or not, but it sounds like you should (plugs & wires are cheap and easy, so it's almost always worth getting new ones). You should definitely do this before thinking about replacing the coils, as they are far less likely to be in disrepair. On the other hand, if they are original then a new set will not hurt (the ones on my car only lasted 18yrs), especially when PartsNMore has 'em cheap.
lhaolpa
XS400 Junkie
If your wires can be unscrewed,take them off,clean them well and put a little di-electric grease where the plug is held. Then put a little silicon or other waterproof stuff on there,and put it back on,and you'll not have that prob again if it's the plug's fault. If you replace the wires,don't use regular automotive wires,use solid or copper core wires.The resistor wires will transmit less current,that's why car coils put out 25,000-40,000 volts and high power coils put out much more. By the way,I wouldn't get rid of the electric start,as you may need it. lha
Charles
XS400 Addict
I just put brand new caps on there, but I'll go ahead and put some dielectric grease on them. Don't see why that would cause the spark to cut out at a higher RPM though. I'll mess around with it more and let you guys know if I find anything out.
Thanks for all the help.
Thanks for all the help.
Charles
XS400 Addict
Just a bump for this. Earlier this week it rained pretty bad. This time the right side wouldn't fire at all and the left was pretty rough at higher rpm too. As the week progressed, something dried out and the left started firing fine pretty much throughout the rpm range, but the right side was still dead above 1200 rpms. At idle, the bike ran ok. Today I went out there and swapped the plug wires/boots from one side to the other. No change. Already swapped the coils. So the issue is up stream of the coils.
Again, at idle, the bike sounds somewhat OK, but as soon as I give it some fuel, it cuts out on the right. At that point, I went ahead and took her around the block to warm her up more, got up to 3rd gear and kind of putted along. Left firing fine, right missing every revolution or so until after 4 minutes, it started kicking in and eventually came back online and ran fine.
I guess I'll just start messing with the multimeter and work my way back from the coils, but this only happens when it rains or when there's a lot of dew, so tomorrow it will probably run fine. Like I mentioned before, maybe I'll hit it with the hose and see if a certain area affects it. Any ideas??
Again, at idle, the bike sounds somewhat OK, but as soon as I give it some fuel, it cuts out on the right. At that point, I went ahead and took her around the block to warm her up more, got up to 3rd gear and kind of putted along. Left firing fine, right missing every revolution or so until after 4 minutes, it started kicking in and eventually came back online and ran fine.
I guess I'll just start messing with the multimeter and work my way back from the coils, but this only happens when it rains or when there's a lot of dew, so tomorrow it will probably run fine. Like I mentioned before, maybe I'll hit it with the hose and see if a certain area affects it. Any ideas??
lhaolpa
XS400 Junkie
You have some condition in which water is entering either the electrical system or the carburetors.When you got it warmed up,it started to run better because it dried out some on the area that is affected. Look at cable exits from the head and the areas exposed to the elements.I don't know how water could enter the carbs,but there may ,in your case,be a way.if modified in some way,who knows?Certainly cars and trucks often have this problem when going through a deep puddle. Good luck sorting out your problem. lha
Charles
XS400 Addict
I doubt it's the carbs. When I take the plug out and ground to the jug, you can see it firing...when you get on the throttle, it stops firing.
lhaolpa
XS400 Junkie
How do you know it stops firing when you give it the throttle?Have you seen it quit firing when you give it the throttle? Do you have an inline spark checker? That's the only way you would know if it's not firing when the throttle is opened,or are you saying that it cuts out when the throttle is opened?
Charles
XS400 Addict
lhaolpa
XS400 Junkie
You must have a short in the kill switch,as that's the only place that the throttle and ignition are located together.Remove the wire from the kill switch and see if it acts the same way.If it does,you really have a unique anomaly. lha
Charles
XS400 Addict
I'll check, but I would think if it was the kill switch, both cylinders would be doing the same thing. With this, it's always the right side that's not firing.
I'm betting it's something in the ignition.
I'm betting it's something in the ignition.
lhaolpa
XS400 Junkie
You should pursue a process of elimination,which is testing all possibilities.The kill switch is a first place to eliminate a possible problem,no matter how remote it may sound to you. Another plausible point is the grounding points of the possibly affected areas,such as the coil,TCI unit,other such components. Get some dielectric grease and put a little on the grounds when checking them. Loose or poor grounds or positive connections can do really strange things to their components,like one part working and another not working. lha
Charles
XS400 Addict
I was out messing with the bike, making sure I didn't notice any more oil leaks. So I crank her up, she starts and the one cylinder it barely firing...once for every two that the other cylinder fires. Anyway, I pop the plug off and of course it dies completely, then as I'm putting it on, I don't get it on all the way and the bike starts running fine. So I'm messing around with it and as long as the plug boot is barely over the plug, the metal inside the boot isn't even touching the end of the plug, it's firing great. When I put the boot all the way, it's back to running like crap. WTF??
