smoking bird on overrun

[loosedougie]

Hi there, first time on here, so sorry for any mistakes.
I have a 51 bird that I brought over from NZ a few years ago. It only has around 18000 miles on it and when I took it to italy a year ago it started to smoke going down the mountain roads only on overrun.
So much in fact that my mate behind me had to stop and wait forr the smoke to clear before he could carry on. I used over 1 litre of oil that day.
On the flats, it does not really use any oil, or smoke. Only down steep hills on overrun.
Two bike shops have looked at it and only looked for oil in the airbox or a blocked breather. Neither have done a compression test to check rings or valve seals. Both are clear from oil.
I have a K&N air filter and micron cans.
A Honda dealer did the valve clearance service before I went to italy. Could they of done something in the service. None of the shims needed to be replaced.
Before this service I never put in a drop of oil.
Would stand for 15months do this?

Welcome any ideas of help on this, or do I have to face the fact that the rings or valve seals have already gone, and is this gonna cost more than this bike is worth. Sucks at having to check oil levels everytime I stop and carrying enough oil to keep a tanker afloat.

Thanks in advance for any advice.

 

[Centaur]

Welcome Dougie

Such a sad first post. I'm sure Jaws:bow: will post on his return from a dirty weekend away! Don't get many Bbirds with that sort of problem at 18000 miles so lets see what transpires!

 

[Bad-Dog]

Hi Mate

Going to back to when I was working as a mechanic, a car that was showing these symptoms would be diagnosed with faulty valve stem seals. Sucking oil past valve stems from top end of motor.
Just my 2c

 

[Vinterceptor]

Hi Mate

Going to back to when I was working as a mechanic, a car that was showing these symptoms would be diagnosed with faulty valve stem seals. Sucking oil past valve stems from top end of motor.
Just my 2c

______________________________________________________________

Yeah, first car I ever bought was a passat estate and it smoked when engine braking. I fitted new valve stem seals and it cured it. Although it was nowhere near the extent of using a litre of oil in a normal day.

Maybe the technician who did yer valve job broke the ceramic on one of the plugs and dropped a bit into the cylinder:dunno::dunno:... just seems strange that this problem only started then and so severe too.

I think the valve stem seals come included with the gasket kit which is about ?150-200 ish

A set of rings is round about ?100 per piston. Either way it needs a good inspection.

Do you know a good local mechanic?

Anyway, if it were me I would ask for advice off the mechanic who does my MOT's (have known him over 30 years), get him to see the smoke and give an estimate for a couple of scenarios. Then if need be I would take the engine out and deliver it to him, or do the job myself.

 

[Smiler 1957]

Did the valve check get done then get ridden to Italy or was the layup between the two , It might just be coincidence that its been in the Dealers . Not being funny but is the bike pottered about ? I would be tempted to try a cheap mineral oil in it and go through like a running in process with it but being quite aggressive with it , then by about the third tank of petrol give it plenty of revs . If you are are not happy about the speeds involved then use the lower gears , but certainly work the engine , unlike the majority of the car world , motorcycle engines are built to withstand a thrashing . After 500 or more miles then change the oil for a semi synthetic . You are not running on fully synthetic i take it and during the layup did you run the engine ?

 

[Smiler 1957]

Not saying its the answer but worth a try . I think Andybird has said the same that all the time an engine is warmed up fully and used the moving parts get used to each other and oil seals and gaskets function properly . To anyone thinking of buying for instance a zero miles RC45 then make sure you get a warranty that covers any engine oil seals , oh and probably a load of other stuff as well .

 

[andyBeaker]

Firstly, w4lc0m3. i went to Watford once, bloody horrible, chucked down all daysh1tehppns but on the bright side we got murdered and won 1-0 (McClair):-0).

Anyway, smoky problem don't sound good and valve seals sounds likely - but has anyone ever come across this on a Bird?? If it were that bad I would have thought the plugs would be fouling in double quick time and killing the motor so you might be in luck and something less worrying (as in 'less expensive'). A compression test should reveal all (or not, if you see what I mean)?

On the bright side, you are really not far from JAWS in Thetford - might be worth booking an audience with the great man. Closer than me, and I take regualar trips up there for the peace of mind a decent service gives.

 

[SpanishJohn]

Hi loosedougie

Sorry to hear about your woes. The problem does sound serious, but is confused by the fact that it does not 'smoke' on the flats. Your bike is clearly burning oil, and logically that oil can only come from

a. Air box
b. Past the rings
c. Past the valve seals

You have removed a) as this has been checked which leaves b) or c).
I note that you are running a K&N filter and micron end cans, so chances are your bike is running very lean / hot at certain RPM. It is possible that v.hot oil (v. low viscosity) is getting past the rings and thus burning or you have burn't the valve oil seals. Lets assume its the former for now. Dump the K&N for an OEM filter and change the oil (and plugs) asap. Use a quality semi synth 10W40. If thye bike still smokes its c).

Good luck
Spanish

 

[loosedougie]

Thanks for the comments so far. The bike wasn't run while it was in storage, it was at the back of a friends garage behind a dryer and numerous babies stuff. It does not really seem to burn oil on the flats, even if I am 'making progress'. When in the alps the amount of oil coming out of the end of the cans was amazing, could of re-bottled it and sold it. At the moment, the exhaust looks normal. When I complain to the garage who did the service, they looked at the bike and could not find any problems when they tilted it up,airbox, plugs. I had to explain it to them that the 800 miles riding on the flats had probably burnt off everything.They in fact told me to get a photo of it smoking as they did not believe me. Like I can do that while riding the bike, and don't have any hill around here steep enough. Bloody useless.
8 hours motor out, 8 hours motor back. plus parts,etc. a lot of cash to part with. May be cheaper to just get rid of it.
I brought a compression tester myself as it is cheaper than paying an hours labour and I am pretty handy on the car. At least it will be a starting point.

 

[andyBeaker]

Thanks for the comments so far. The bike wasn't run while it was in storage, it was at the back of a friends garage behind a dryer and numerous babies stuff. It does not really seem to burn oil on the flats, even if I am 'making progress'. When in the alps the amount of oil coming out of the end of the cans was amazing, could of re-bottled it and sold it. At the moment, the exhaust looks normal. When I complain to the garage who did the service, they looked at the bike and could not find any problems when they tilted it up,airbox, plugs. I had to explain it to them that the 800 miles riding on the flats had probably burnt off everything.They in fact told me to get a photo of it smoking as they did not believe me. Like I can do that while riding the bike, and don't have any hill around here steep enough. Bloody useless.
8 hours motor out, 8 hours motor back. plus parts,etc. a lot of cash to part with. May be cheaper to just get rid of it.
I brought a compression tester myself as it is cheaper than paying an hours labour and I am pretty handy on the car. At least it will be a starting point.

Try not to get too pisssed off; the odds are that whatever the problem is it is probably not anything like as bad as you think it is at the moment. I do think a trip to JAWS might be a good idea. Norfolk is nice and flat as well:-0)

 

[loosedougie]

Also was using semi synth, but a mate has just given me 5 litres of fully synth.
Don't know if that will make things worse, but it wont have time to get dirty. I know it is not correct for the bike.
Thanks SpanishJohn, will try your advice. I asked about the K&N filter and the mehanics said wouldn't cause my problem, but I did also change the OEM filter to K&N at the major service.

 

[andyBeaker]

Also was using semi synth, but a mate has just given me 5 litres of fully synth.
Don't know if that will make things worse, but it wont have time to get dirty. I know it is not correct for the bike.
Thanks SpanishJohn, will try your advice. I asked about the K&N filter and the mehanics said wouldn't cause my problem, but I did also change the OEM filter to K&N at the major service.

I think I am right in saying FFS DO NOT PUT FULLY SYNTH IN BIRD but someone will be along to confirm or deny shortly.

 

[Jaws]

Also was using semi synth, but a mate has just given me 5 litres of fully synth.
Don't know if that will make things worse, but it wont have time to get dirty. I know it is not correct for the bike.
Thanks SpanishJohn, will try your advice. I asked about the K&N filter and the mehanics said wouldn't cause my problem, but I did also change the OEM filter to K&N at the major service.

Quit obviously the mechanic the mechanic is a tosser just after flogging you any shite he can make money on... ORRRR he knows sod all about the bird ( dunno what is worse ! )
Quite possibly putting fully synth oil in will eventually cure the problem for you..
It will ensure you have to buy another engine sooner or later ! LOL !!

 

[loosedougie]

Ok have done the compression test today.
I don't think it is good news. figure below in psi

..............no oil in bore............... oil in bore
1 .................119....................... 140
2 ................128........................ 158
3 ...............125 .........................153
4 ..............120 ..........................158

I believe on a new bird the psi should be around 185. On a 2001 bike are the above figure good, bad, fatal?

 

[andyBeaker]

Ok have done the compression test today.
I don't think it is good news. figure below in psi

no oil in bore oil in bore
1 119 140
2 128 158
3 125 153
4 120 158

I believe on a new bird the psi should be around 185. On a 2001 bike are the above figure good, bad, fatal?

I am no expert on compression testing, but I would have thought that the fact that the figures are in a fairly tight range would be good news? bad news would be if one was way off the others i.e. big problem in one cylinder. Unlikely all 4 are knackered at the same time I would have thought?

I still bet that when this is bottomed out that it is not going to be as bad as you probably think it is at the moment; we have all been there!!

Presumably you had a good look at the plugs while they were out? What did they look like - oily, dry, sooty...?

 

[loosedougie]

To me the plugs look fine, dry with a slight whiteish tinge.
Took some pics of them, will try to attach them

 

[ray pinder]

If those comp tests were done with the throttle OPEN then I would suggest removing the head to investigate;unfortunately this means engine removal.

 

[Jaws]

Beat me to it but yes, must do compression tests on full throttle opening

 

[robsbird]

being a bit dum at times but why would the throttle open change to comp test

as I would have thought all valves would have to be closed at the height of compression, at give or take top dead centre........

so I would have to say check the timing marks first.......h1d1ng2

 

[Jaws]

Sorry Rob, yes mate, you are indeed being a bit dumb ..

You check compression by putting the gauge in to the plug hole, holding the throttle open and then hitting the start button.. You allow the engine to go through approx 6 compression strokes to get the reading you are looking for.

You need the throttle open to be sure you are filling the cylinder with gas ( air in this case ) to compress.
With the throttle closed you form a partial vacuum in the inlet tracts which, when the inlet opens detracts from the compression figure

No idea what you refer to to be honest mate...