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placidfemme
27th April 2007, 10:50
I've just gone and searched through all my previous threads because I'm sure I've mentioned this issue before... but I can't seem to find anything... so here goes...

~~

As you all know I ride a '92 Kawasaki ZXR250C. I've had the bike for about 2-2.5 years now.

Before I wrote the ZXR off (Dec 2005) I started to notice white smoke coming from the front end.

Its only noticable in the dark (with the headlight on of-course). I first started noticing it in the mornings when I used to start work at 6.30am. You could see the smoke wafting up infront of the light and also wafting up the inside of the fairings past the instruments, sometimes a lot of smoke and sometimes just a little bit.

Then I started working late and noticed the smoke when I would get home at about 9pm.

Recently I havn't been riding much in the dark, but since I've started my second job and I finish at 9pm, its obviously dark, and last night again I noticed the smoke when I got home, I called Sam out and pointed it out to her, so I know its not just in my head.

Now pre-2005 I took the ZXR into Red Baron twice to get them to try and find what is causing the smoke. Both times Mike (the head mechanic at the time) couldn't find anything that he thought would cause the smoke. He said to just not worry about it.

Since then the bike has been written off, re-complied & registered, passed 2 WOF's and had a service or two, and none of those things have stopped the smoke.

These are the things I considered:

1. Possible fork oil leak somewhere thats leaking onto something hot causing smoke? -- Had the fork seals and oil replaced when before the bike was re-complied & registered & WOF'd. So can't be that.
2. Leaking brake fluid from the front break somehow? -- I've been keeping an eye on my front break fluid levels. It hasn't dropped significantly over the last few months, so unless a small amount like say... 1 drop can make a fair bit of smoke, then I doubt its the break fluid.
3. Radiator -- I've checked over the radiator and it doesn't seem to have any cracks/holes in it, so I don't think radiator coolant is dripping onto the header pipes to cause the smoke...

So I'm at a loss. The smoke smells kinda sweet if that makes sense. I don't think its affecting the performance of the bike, and I'm also unsure if it smokes all the time as I can only see it in the dark...

But whether or not its affecting the performance or safety of the bike, it shouldn't be smoking.

Can anyone suggest what else to look at/for to figure this out?

Thanks in advance

PF :innocent:

SARGE
27th April 2007, 10:53
I've just gone and searched through all my previous threads because I'm sure I've mentioned this issue before... but I can't seem to find anything... so here goes...





park your bike over a piece of cardboard after a run.. note where the drips are in the morning ..

if it smells sweet .. could be coolant leaking on headers etc ..

imdying
27th April 2007, 11:03
I've seen some really badly leaking forks on a ZXR250, even they weren't enough to coat the headers... you'd know anyway, your brakes would be covered in it.

Brake fluid burns with a white smoke, but you'd know if you were losing that.

Your brakes aren't binding? They'll smoke the pads if they get too hot, but I'd like to think you'd notice that too!

Any plastic on the headers? Either a fairing rubbing, a bag that has gotten caught, etc?

Sarge's trick will work fine for looking for leaks :yes:

placidfemme
27th April 2007, 11:06
park your bike over a piece of cardboard after a run.. note where the drips are in the morning ..

if it smells sweet .. could be coolant leaking on headers etc ..


I'll try that tonight, but I don't think there are any "drips" from the bike, when I noticed the smoke last night I ran my hands voer everything I could reach (and that wouldn't burn me) to feel for anything wet or damp and didn't find anything. But I'll give it a shot.

I'm planning on giving the bike a good ole clean on Sunday if the weather ain't too bad, and I'll double check the radiator for cracks/holes etc

bistard
27th April 2007, 11:06
Sarge is on to it,maybe even remove the bellypan
One question I have is,is it smoke or steam??
Smoke will linger in a cloud,steam will dissapate quickly??

SARGE
27th April 2007, 11:10
I'll try that tonight, but I don't think there are any "drips" from the bike, when I noticed the smoke last night I ran my hands voer everything I could reach (and that wouldn't burn me) to feel for anything wet or damp and didn't find anything. But I'll give it a shot.

I'm planning on giving the bike a good ole clean on Sunday if the weather ain't too bad, and I'll double check the radiator for cracks/holes etc

when you are cleaning it .. check loose hose clamps, overflow lines, etc.. might py to remove the plastics to check everything over ..

placidfemme
27th April 2007, 11:10
I've seen some really badly leaking forks on a ZXR250, even they weren't enough to coat the headers... you'd know anyway, your brakes would be covered in it.

Brake fluid burns with a white smoke, but you'd know if you were losing that.

Your brakes aren't binding? They'll smoke the pads if they get too hot, but I'd like to think you'd notice that too!

Any plastic on the headers? Either a fairing rubbing, a bag that has gotten caught, etc?

Sarge's trick will work fine for looking for leaks :yes:

As mentioned the fork seals and oil where replaced recently (about Nov last year... around abouts anyway), so I really doubt its that, also last night I felt around my forks and there was nothing oily there...

My front brake has felt "soft" lately, but it still works fine.

My front disc's and pads are new too (only had them replaced when re-complied... so again last year in about Oct/Nov) The brakes squeak a little bit sometimes, but only when braking hard.

*runs downstairs to check that my fairings arn't touching the headers and theres no plastic in there*

placidfemme
27th April 2007, 11:13
Sarge is on to it,maybe even remove the bellypan
One question I have is,is it smoke or steam??
Smoke will linger in a cloud,steam will dissapate quickly??

I'm pretty sure its smoke. Last night it seemed to hang around for a bit before disappearing. But in the past its varied... sometimes it wafts around for a bit other times its barely noticable etc


when you are cleaning it .. check loose hose clamps, overflow lines, etc.. might py to remove the plastics to check everything over ..

Sweet as I'll try that too :)

MSTRS
27th April 2007, 11:43
.... I can only see it in the dark...



You are eating too many carrots??

Seriously, I remember that thread vaguely....think it was coming out of your front hub, around the speedo drive??

placidfemme
27th April 2007, 12:13
You are eating too many carrots??

Seriously, I remember that thread vaguely....think it was coming out of your front hub, around the speedo drive??

lol I hate carrots :sick:

Yeah I thought I had posted about it before... I'll double check

Edit: Here it is:

http://www.kiwibiker.co.nz/forums/showthread.php?t=13025&highlight=smoke+from+the+front

Roj
27th April 2007, 12:26
Could be a small amount of oil leaking from the cam cover seal, if it drips on to the exhaust you would get the smoke once things are hot. a very small leak would not show up easily.:scooter:

vifferman
27th April 2007, 12:32
Where does your strange oil filler vent pipe go to? It's not coming from that is it (fumes wandering up underneath the tank and out)?

See if you can sniff up some of the smoke and taste it - is it oily, burny, plasticky, greenhouse-gassy, or what?
Maybe your bike actually had a previous life in the facory where they make the smoke that's put inside electrical components. That could be really handy, because if any of us had leaks in our electrical components and the smoke got out, instead of having to buy new ones, we could just get them refilled from your ZXR. :yes:

xwhatsit
27th April 2007, 12:45
Could be a small amount of oil leaking from the cam cover seal, if it drips on to the exhaust you would get the smoke once things are hot. a very small leak would not show up easily.:scooter:

This is what mine was doing. You're right, despite the quantity of oil, it was actually quite difficult to discover where it was coming from without a lot of testing. Ended up replacing seals that didn't need replacing.

Macktheknife
27th April 2007, 12:54
Check your headers for stains or leak marks and back track from there. Smoke generally means a heat source, work at it backwards and see what you find.

placidfemme
27th April 2007, 12:56
Well my oil overflow pipe (or whatever its called) come out under the bike near the left side riders footpeg. The petrol overflow pipe (at least I think thats what it is) and the coolant overflow pipe come out near the right rider footpeg.

The smoke is not coming from under the bike but the front end. So I don't think it's the overflow pipes dripping on anything. And even if they were dripping, they are no-where near anything that gets hot... the worst I can see happening if any of those pipes are dripping overflow luquid is that it'll drip right onto the patch my rear tyre will go over (when moving). So nothing to cause smoke there.

I just went through and re-read the whole thread posted above that I did in 2005 asking about the same problem.. wow I've learnt a lot since then... anywho... the only thing from that thread that I havn't done/checked is taking the brake calipers or whatever apart and checking for brake fluid leaks...

Kwaka14
27th April 2007, 13:03
Check your kleen air system (what kawasaki call it now) which is a valve that comes from the top of the rocker cover and has a hose that runs in to the airbox, it sounds like it could be a bit of blow-by to me - older engines have exhaust smoke move past the exhaust valve seals in to the rocker cover area and there is always vapour present here anyway. The other thing to check is the rocker cover bolts as the washer at the top wears over time and leaks oil across the top of your rocker cover which runs down across your headers... usually a small volume and not much of a hazard

placidfemme
27th April 2007, 13:07
Check your kleen air system (what kawasaki call it now) which is a valve that comes from the top of the rocker cover and has a hose that runs in to the airbox, it sounds like it could be a bit of blow-by to me - older engines have exhaust smoke move past the exhaust valve seals in to the rocker cover area and there is always vapour present here anyway. The other thing to check is the rocker cover bolts as the washer at the top wears over time and leaks oil across the top of your rocker cover which runs down across your headers... usually a small volume and not much of a hazard

Um... I know where my air filter is. But don't know what you mean by rocker cover, kleen air system, exhaust valve seals, rocker cover bolts etc.

Would I be able to see it if its close to the air filter (need to remove the fairings and then the tank to get to the airbox/filter), so I'm assuming it close to that

Kwaka14
27th April 2007, 13:23
Um... I know where my air filter is. But don't know what you mean by rocker cover, kleen air system, exhaust valve seals, rocker cover bolts etc.

Would I be able to see it if its close to the air filter (need to remove the fairings and then the tank to get to the airbox/filter), so I'm assuming it close to that

The rocker cover is the top cover of the engine, the valve /kleen air system is a hose coming from the rocker cover. I would guess that it's probably just a very small weep coming from either the washers/bolts holding down the rocker cover or it's oil vapour from the valve/hose that runs from this.

placidfemme
27th April 2007, 13:29
The rocker cover is the top cover of the engine, the valve /kleen air system is a hose coming from the rocker cover. I would guess that it's probably just a very small weep coming from either the washers/bolts holding down the rocker cover or it's oil vapour from the valve/hose that runs from this.

ahhh ok.

I'm planning on giving the ZXR a good ole clean on Sunday if the weather holds up, when I do that I'll take the tank off and have a look and see if I can spot what your describing :)

Sam I Am
27th April 2007, 23:44
perhaps its electrical !! Is your headlight bulb the correct wattage ?
Iv'e smoked wiring before putting a overated bulb that the lume couldent handle.
or it could be some random electrical fault/short.

placidfemme
30th April 2007, 09:57
perhaps its electrical !! Is your headlight bulb the correct wattage ?
Iv'e smoked wiring before putting a overated bulb that the lume couldent handle.
or it could be some random electrical fault/short.

I'm not too sure about that. As mentioned the smoking was happening before I wrote the ZXR off in 2005. When i wrote it off, part of the damage was a damaged bublb in the headlight (no dip beam), so i had the bulb replaced (at like $40 or $50 for the bulb... grrr). And its been smoking since then too... so I'm not sure if that would be the problem.

I didn't get a chance to take the ZXR apart this weekend and clean it, Sam was sick all day Saturday so we had to postpone our Saturday plans to Sunday and therefor no time for my bike :(

Pwalo
30th April 2007, 10:31
Look if it's smoking something is leaking on to your headers.

As everyone has suggested, give the front of your engine a good clean up, start it without the lower fairings on and look for any leakage. Logically it must be something above your headers, so look there.

Good luck. It can be a bummer having to check these things out, but well worth it in the long run.

I think you need to get a manual or a down load of one to help you with id'ing the parts of your bike.

vamr
30th April 2007, 10:49
Hrm, late at night or early in the morning... getting colder... was it raining per chance?

placidfemme
30th April 2007, 11:05
Hrm, late at night or early in the morning... getting colder... was it raining per chance?

Nope no rain at all. I rode to work this morning in the rain/showers and when I got to work I had steam (not smoke) coming up from the headers. It disappeared before I could even take my helmet off to have a look. So not the same as the smoke I've seen before...

Fooman
30th April 2007, 14:04
The smoke smells kinda sweet if that makes sense.

If it is whiteish smoke, and has a "sweet" smell to it, it's probably coolant leaking somewhere onto something quite hot (e.g. headers). I had the same experience after my GSXR250 got knocked over at a car park at uni many years ago. Everytime I came to a stop, it was in a cloud of sickly steam/smoke as the (busted) radiator splashed onto the headers.

Cheers,
FM

placidfemme
30th April 2007, 14:25
If it is whiteish smoke, and has a "sweet" smell to it, it's probably coolant leaking somewhere onto something quite hot (e.g. headers). I had the same experience after my GSXR250 got knocked over at a car park at uni many years ago. Everytime I came to a stop, it was in a cloud of sickly steam/smoke as the (busted) radiator splashed onto the headers.

Cheers,
FM

Yeah I'm thinking it might be that, I can't think of much else other than the brakes...

I've checked over the radiator already, but when i get a chance to take the fairings off again I'll do a much more in-depth inspection and double check there are no cracks/holes that could be dripping onto the headers...

Max Preload
30th April 2007, 15:47
Yeah I'm thinking it might be that, I can't think of much else other than the brakes...

I've checked over the radiator already, but when i get a chance to take the fairings off again I'll do a much more in-depth inspection and double check there are no cracks/holes that could be dripping onto the headers...

Pressure test it. If it's such a minor leak that it's not dumping coolant, you'll probably not find it without forcing a leak using pressure.

Of course, it could simply be rain water pooling somewhere and then sloshing about and dripping onto the headers or engine but that won't be accompanied by the sweet smell of coolant.

placidfemme
30th April 2007, 15:51
Pressure test it. If it's such a minor leak that it's not dumping coolant, you'll probably not find it without forcing a leak using pressure.

Of course, it could simply be rain water pooling somewhere and then sloshing about and dripping onto the headers or engine but that won't be accompanied by the sweet smell of coolant.

Do I need any special machines to pressure test it?

Max Preload
30th April 2007, 15:59
Do I need any special machines to pressure test it?

A cooling system pressure tester. All radiator shops have them - they'll pump >20psi in there for you and any leaks will become obvious since the most the system usually sees is 14psi. All you need is easy access to the cap.

rookie
30th April 2007, 19:17
surely the drip test would show up any leaks though...if its such a small leak that only warm fluid under operating pressures could make its way out of the crack/hole/split then leave the bike idling for a little while after a ride to allow any drips to fall onto the piece of cardboard mentioned earlier in this thread.

If you want to check for caliper leaks - check the wheel to see if fluid is finding its way there...or wait till the morning after you've been for a ride the previous day to give enough time for the leaks to form.

Max Preload
1st May 2007, 00:21
surely the drip test would show up any leaks though...if its such a small leak that only warm fluid under operating pressures could make its way out of the crack/hole/split then leave the bike idling for a little while after a ride to allow any drips to fall onto the piece of cardboard mentioned earlier in this thread.

If you want to check for caliper leaks - check the wheel to see if fluid is finding its way there...or wait till the morning after you've been for a ride the previous day to give enough time for the leaks to form.

It would be a rare leak that drops fluid directly onto the cardboard without finding it's way to the ground via numerous wires and hoses. Pressurising the cooling system beyond normal operating pressure will immediately pinpoint a leak.