Weird, Loud Noise in Heavy Rain

[StolenMadWolf]

This is something that has recently started occuring with my nearly 10 year old Kawasaki KLE500. If I ride the bike in heavy rain, it sounds normal at first, then will suddenly sound weird. It's hard to describe other than the bike sounding far louder than it should be normally at a set gear. Maybe sounding a little bit more... 'rumbly' maybe? Yeah, not really a word but it's hard to describe.

The engine still works as normal, I still get the same power output out of it but the noise comes and goes as I ride and the moment the rain stops, the bike is back to normal.

Any idea what might be causing this? I just got the bike heavily redone as a few issues were creeping in due to the age of some of it's parts and the wear on them. I've also been trying to get the chance to get some oil and high temperature paint to clean up the corrosion on the pipes and protect them but I have not had the chance.

Any ideas?

[Tango]

Does it only make the noise when you're moving? Maybe it's down to tyres making more road noise when its raining hard?

[StolenMadWolf]

Actually, just thinking on it the noise will change as you rev the engine.

As for occuring whilst moving, it starts when I get to around 20-40 mph after a while, but will persist even if I stop.

Beyond that, the noise is on and off.

The engine still works fine even with the noise as far as I knlw so I'm guessing it's something to do with the exhaust.

[Stu]

Sounds like it's misfiring

[StolenMadWolf]

Misfiring on and off in heavy rain only? Just seems a little too coincidental.

[Baldrick]

Misfiring on and off in heavy rain only? Just seems a little too coincidental.

 

It's possible the rain is getting in the plugs/Carbs/Coil causing the misfire.

[StolenMadWolf]

Misfiring on and off in heavy rain only? Just seems a little too coincidental.

 

It's possible the rain is getting in the plugs/Carbs/Coil causing the misfire.

 

How could I possibly fix this if that's happening?

[Baldrick]

Misfiring on and off in heavy rain only? Just seems a little too coincidental.

 

It's possible the rain is getting in the plugs/Carbs/Coil causing the misfire.

 

How could I possibly fix this if that's happening?

 

For a quick fix for the plugs/coil WD40 is your friend, spray it all over them, carbs would probably need a proper looking at, cleaning etc.

[Guest]

A misfire isn't consistent with what you are describing, you've said the engine works as normal and you get the same power out of it for a start.

Loosing one cylinder due to a misfire you could possibly miss on a 4 cylinder, but not on a parallel twin, the engine would be running rough as a tumble dryer with a pair of trainers in and you'd loose over half the engines power.

A very intermittent misfire where it just drops a cylinder for one firing cycle at a time might go undetected, but you've described a fairly constant noise.

[fastbob]

This is something that has recently started occuring with my nearly 10 year old Kawasaki KLE500. If I ride the bike in heavy rain, it sounds normal at first, then will suddenly sound weird. It's hard to describe other than the bike sounding far louder than it should be normally at a set gear. Maybe sounding a little bit more... 'rumbly' maybe? Yeah, not really a word but it's hard to describe.

The engine still works as normal, I still get the same power output out of it but the noise comes and goes as I ride and the moment the rain stops, the bike is back to normal.

Any idea what might be causing this? I just got the bike heavily redone as a few issues were creeping in due to the age of some of it's parts and the wear on them. I've also been trying to get the chance to get some oil and high temperature paint to clean up the corrosion on the pipes and protect them but I have not had the chance.

Any ideas?

There aren't bright flashes in the sky immediately before the rumbley noise occurs are there?

[TimR]

Nothing changed recently

Like a new helmet or top box put on etc ...

[Northern Biker]

Does it have open air filters like K&N?

[fastbob]

Why not start it up , get up to running temperature then spray water all over it with a hosepipe to simulate heavy rain . Might help to pinpoint what's happening. I've got an ER5 which has the same engine and having read the whole post again I have to say I'm completely baffled. Its the fact that performance doesn't change that makes no sense at all. Water just doesn't cause a bike to make more noise. It's not because you unconsciously start riding differently when it rains is it ? I do alter my style of riding and if its wet and cold I have to lift my visor to stop steaming up . Visor up , more sound in my helmet and running slower thus decreasing wind noise could give the impression that the bike sounds different. The mind plays tricks.

[StolenMadWolf]

Since more replies popped up then I thought and I haven't been on for a while, I might as well just say this. Seems like water might be getting to a sparkplug and causing misfires in heavy rain, at least, that's what someone said a while ago IRL and on here as well.

[RantMachine]

Ta for updating us

[fastbob]

Since more replies popped up then I thought and I haven't been on for a while, I might as well just say this. Seems like water might be getting to a sparkplug and causing misfires in heavy rain, at least, that's what someone said a while ago IRL and on here as well.

 

Well that's what I suspected all along BUT because you said there was no loss of power I didn't say that was what it could be. If you go onto one cylinder on a KLE ( or an ER5 which has the same engine ) you should definitely FEEL it AND hear it. The good news is that KLE ht leads can be detached from the coils so I would get a metre of standard ht lead , not squashy silicone lead , and just replace both leads. This will probably fix the problem.