View Full Version : 2 stroke emissions testing?
Intruder VS
16th June 2019, 12:00
Hi guys I?m sitting at home bored, sick feeling sorry for myself and started thinking about a old sticker I found on the tail plastic on the 350LC I?m restoring, had little laugh when I read it but the ?produces less pollution? part made me think compared to modern vehicles that?s no where near correct anymore and to add to that I took my 87 RZ for WOF at local testing station a few months ago and everything checked out fine till I started it up to ride down to where they issue the wof and the tester noticed the smoke and said oh dear it smokes a bit that may be a fail, he revved it a couple of times which made it smoke more ,bike was still cold from the short ride to testing station which didn?t help. I explained it?s a 2 stroke and smokes a bit more when cold and if it didn?t smoke at all I would be very worried which didn?t seem to impress the guy, luckily another tester came over and said to the other guy it?s fine that?s the way they are told me to go to exit and wait while he issued the wof.
So all ended up ok but made me wonder when the greenies will jump on the emissions thing and call for emission testing to be part of wof testing? So what then for our precious 2 smokes will they be outlawed?
Sorry for rambling on boredom will do that I guess.
AllanB
16th June 2019, 12:19
There has been talk of shoving a tester up ya pipe for WOF's for years.
The problem will be exactly what you encountered, a inspector who is applying a modern standard to something made decades ago.
In NZ we are very lucky with our motorcycles - we can get away with a lot of modifications that don't require certification, or probably should but no-fucks are given. Add to that list de-cat of your exhaust system, which appears to be completely overlooked at WOF time (self included on this subject).
A friend of mine took his early 80's Holden for a WOF some time back - the inspector was going to fail it due to excessively heavy steering - until it was pointed out that the car did not have power steering and they was the way it was built. He had to go get a 'older' inspector to verify the way things were.
Old Steve
16th June 2019, 12:33
Smoke-free 2-stroke motorbike oil is available, in fact most 2-stroke motorbike oils should now be smoke-free. The formulators use poly-iso-butane (PIB) as the base fluid and this totally decomposes into CO2 and H2O in the combustion chamber, eliminating exhaust smoke and fouled exhaust ports. From memory PIB decomposes at 185 deg C, so even a cold motorbike engine shouldn't smoke much/for a very short time/at all.
Navy Boy
16th June 2019, 16:36
I guess next time you'll just need to take the long route to the WOF centre so that it's properly warmed up. Bike emissions testing is something that will come to us sooner or later. Bike fuel consumption has long been something that most of us don't really talk about but it's now starting to become rather more important to the manufacturers what with Euro 4 and 5 regs all but upon us. :yes:
george formby
16th June 2019, 17:12
Smoke free 2t oil? Intrigued I am.
I use Motul 700 (maybe) and it is low smoke. I think this applies to how far it floats before coming back down again.
My 2t's are still original and running the factory oil system which is probably leaning towards longevity but they do like to puff cold, at low revs and high torque situations.
Last time I got a WoF, after filling the shop with blue smoke, the only comment I got was how nice the smell was.
Hopefully some sense will prevail with older vehicles, unlike older houses, that you can't make an old vehicle 21st century compliant.
The only new 2t's available now are dirt bikes and possibly scoots. With FI on 2t's, emissions will come down, I'm reading 100:1 ratios at certain revs..:shit:
Navy Boy
16th June 2019, 17:18
Smoke free 2t oil? Intrigued I am.
I use Motul 700 (maybe) and it is low smoke. I think this applies to how far it floats before coming back down again.
My 2t's are still original and running the factory oil system which is probably leaning towards longevity but they do like to puff cold, at low revs and high torque situations.
Last time I got a WoF, after filling the shop with blue smoke, the only comment I got was how nice the smell was.
Hopefully some sense will prevail with older vehicles, unlike older houses, that you can't make an old vehicle 21st century compliant.
The only new 2t's available now are dirt bikes and possibly scoots. With FI on 2t's, emissions will come down, I'm reading 100:1 ratios at certain revs..:shit:
Blimey - 100:1. Our old off road 2 strokes used to run 35-40:1 if memory serves...
george formby
16th June 2019, 17:45
Blimey - 100:1. Our old off road 2 strokes used to run 35-40:1 if memory serves...
Exacary.
With correctly mapped FI you could ride 90 Mile beach tapped oot and not have a seizure when you shut the throttle, the mapping would allow overfuelling to cool off the head. Just a thought and not emissions friendly.
Potentially, if exhaust emissions are measured by the same parameters as noise, a certain (relatively low) rev range, the bikes could be running pretty clean.
IIRC Aprillia showcased a 2t scooter engine a few years ago with an injection system like a common rail diesel. It was Euro 4 compliant. Dunno if it went into production.
AllanB
16th June 2019, 18:00
Old vehicles will get exemptions of some form - may be km limited or with the current government more likely you'll be taxed higher if you own a pre XX vehicle.
F5 Dave
16th June 2019, 21:22
At least 2 bikes past me in the forest today and smelt of Castol R30. It was great.
Ixion
16th June 2019, 23:20
First registered before 1 January 1960 with four-stroke engine manufactured before 1 January 1960, or
Vehicle with two-stroke engine or rotary engine.
The smoke produced is not noticeably and significantly more visible than it would have been when the vehicle was manufactured and supplied with the fuel recommended by the manufacturer (Note 4).
Note the above quote from the VIRM manual ( the WOF rule book). Two smokers are ok so long as they don't produce significantly more smoke than when new. This I know, because I was the guy who spoke with LTSA as they were then, when the emissions rules were first proposed,and explained about two strokes. After a high level discussion at LTSA they agreed that two strokes should, effectively, be exempt.
The government have had a problem with emissions testing as part of WOF, because for years NZ had a motor assembly industry. But the vehicles we assembled here had the emission control stuff left off or ineffective, it was cheaper. so. Having allowed these vehicles initially, it is difficult to now turn round and say they are illegal. aNd since vital parts of the emission control hardware were often simply left off, those vehicles never be made compliant.
So if a WOF inspector tries to fail your ring-a-ding-ding on the grounds of smoke, just tell him To read his manual
rastuscat
17th June 2019, 08:59
Bikes appear to be smokier because you can see the smoke. Thing is, emissions aren't just the smoke you can see. For this reason, a 350cc bike emits less hydrocarbons than a 1600cc car despite appearing to be a lot worse.
I'm not sure about this, but it kind of makes sense. Any of you scientist types care to advise?
Navy Boy
17th June 2019, 14:26
In basic terms the nasties emitting from the exhaust are directly proportional to the amount of fuel the bike/car uses. Hence my comment earlier about bikes' fuel consumption figures and how the manufacturers are having to pay more and more attention to this area.
Bikes tend not to sell on account of how efficient they are but this needs to start figuring in buyers' minds a lot more. Especially if bikes are to be taken seriously as an ecologically-friendly alternative to other forms of transport.
The nice bit to this is that Euro 3/4 and soon-to-come 5 rules tend to make engines more efficient and hence better on fuel anyway. My 1995 Triumph Thunderbird and 2017 Thruxton are prime examples of this with the Thunderbird giving 15-16 km/litre and the Thruxton some 20-22 km/litre. This still being possible despite the Thruxton generating significantly more power and being rather nice and responsive to ride.
A bit like the noise aspects of the Euro 4 regs when a lot of people, myself included, were concerned that the new regs would stifle bikes' exhaust notes even more. However the reverse appears to be true (Owing to the way in which the sound is now measured apparently) with many Euro 4-compliant machines being more pleasing to the ear in standard trim.
So - It's not all bad news - Especially when older machines are effectively exempt as described above.
We live in a golden age of bike design and capability.
rastuscat
18th June 2019, 14:28
In basic terms the nasties emitting from the exhaust are directly proportional to the amount of fuel the bike/car uses. Hence my comment earlier about bikes' fuel consumption figures and how the manufacturers are having to pay more and more attention to this area.
Bikes tend not to sell on account of how efficient they are but this needs to start figuring in buyers' minds a lot more. Especially if bikes are to be taken seriously as an ecologically-friendly alternative to other forms of transport.
The nice bit to this is that Euro 3/4 and soon-to-come 5 rules tend to make engines more efficient and hence better on fuel anyway. My 1995 Triumph Thunderbird and 2017 Thruxton are prime examples of this with the Thunderbird giving 15-16 km/litre and the Thruxton some 20-22 km/litre. This still being possible despite the Thruxton generating significantly more power and being rather nice and responsive to ride.
A bit like the noise aspects of the Euro 4 regs when a lot of people, myself included, were concerned that the new regs would stifle bikes' exhaust notes even more. However the reverse appears to be true (Owing to the way in which the sound is now measured apparently) with many Euro 4-compliant machines being more pleasing to the ear in standard trim.
So - It's not all bad news - Especially when older machines are effectively exempt as described above.
We live in a golden age of bike design and capability.
I tend to take the car to work, despite it using more fuel. Not a lot more, but more. My car is a turbo 1000cc, 3 cyl rocket ship. My bike is a 6 cyl, 1600cc rocket ship.
The car uses tyres every 40 - 45 thousand km. The bike every 12000 km. The 10K service on the car is way cheaper than the 10K service on the bike.
It's not just about the petrol.
Navy Boy
18th June 2019, 15:18
I tend to take the car to work, despite it using more fuel. Not a lot more, but more. My car is a turbo 1000cc, 3 cyl rocket ship. My bike is a 6 cyl, 1600cc rocket ship.
The car uses tyres every 40 - 45 thousand km. The bike every 12000 km. The 10K service on the car is way cheaper than the 10K service on the bike.
It's not just about the petrol.
Very true Rastuscat. Bikes' running costs are one of those things that it pays not to pay too much attention to in my experience. :shit:
However from an emissions and hence economy perspective bikes have been needing to do a lot better for many years now. Plus - And this isn't intended as any sort of dig (I rather like the K1600 models) most people aren't going to be looking at a K1600 Beemer as an everyday commuter. Not unless you compare it to the BMW car equivalent. Something like say a high end 5, 6 or 7 series at any rate. :yes:
george formby
18th June 2019, 17:38
Very true Rastuscat. Bikes' running costs are one of those things that it pays not to pay too much attention to in my experience. :shit:
However from an emissions and hence economy perspective bikes have been needing to do a lot better for many years now. Plus - And this isn't intended as any sort of dig (I rather like the K1600 models) most people aren't going to be looking at a K1600 Beemer as an everyday commuter. Not unless you compare it to the BMW car equivalent. Something like say a high end 5, 6 or 7 series at any rate. :yes:
Kinda wandering off topic but the new T7 Yamaha, CP2 parallel twin motor, has a 16ltr tank and is taking a big shot at the adventure bike market which demands big distances between fills. Yamaha claim 350kms to a tank, summit like 4.6ltrs / 100km. That strikes me as reasonably efficient considering it has the aerodynamics of a trampoline. I suspect it will only see the dealer for it's service.
Bikes designed purely for commuting are far more frugal.
One thing I've noticed wid 2t's, which abandons any emissions arguments, they love petrol! The more you stick in, the more they seem to like it. My DT230 is re-jetted (WR 200 jetting), goes like a cut cat and will slurp 11ltrs in less than 150km of grins.
rastuscat
18th June 2019, 19:41
Kinda wandering off topic but the new T7 Yamaha, CP2 parallel twin motor, has a 16ltr tank and is taking a big shot at the adventure bike market which demands big distances between fills. Yamaha claim 350kms to a tank, summit like 4.6ltrs / 100km. That strikes me as reasonably efficient considering it has the aerodynamics of a trampoline. I suspect it will only see the dealer for it's service.
Bikes designed purely for commuting are far more frugal.
One thing I've noticed wid 2t's, which abandons any emissions arguments, they love petrol! The more you stick in, the more they seem to like it. My DT230 is re-jetted (WR 200 jetting), goes like a cut cat and will slurp 11ltrs in less than 150km of grins.
I've had 3 F800STs, BMW parallel twins. All were fuel misers, with good range from a 17 litre tank. About 4.6 l/100. It's been around long enough to be a good idea.
Navy Boy
19th June 2019, 10:38
It does make you wonder (And kind of getting back to the point in the OP) just what 2-strokes would be capable of consumption/emissions-wise if the manufacturers had been able to persist with them and thrown R+D time and money at them over the past 20+ years.
Direct injection (Such as Piaggio's idea) would be great to see - I'd be fascinated to see just what the art of the possible is with such a set up.
As for the F800 series Beemers - Great bikes that happened to be crackingly good on fuel too. From what I can see the only big (Over 500cc) mainstream bikes that focus on this aspect now are the NC 750 Hondas though I'm not sure what the latest F850 series Beemers are like. :scooter:
george formby
20th June 2019, 18:47
It does make you wonder (And kind of getting back to the point in the OP) just what 2-strokes would be capable of consumption/emissions-wise if the manufacturers had been able to persist with them and thrown R+D time and money at them over the past 20+ years.
Direct injection (Such as Piaggio's idea) would be great to see - I'd be fascinated to see just what the art of the possible is with such a set up.
:scooter:
Tell me about it!
I suspect road going 2t's were canned, not due to emissions, but the realisation that advancing the technology would cut into profits. The CRM Active Radical, fuel injection, computer engine management, CAT's, performance and a dearth of moving parts would be less profitable than 4t's which require a higher capacity for the same bang and higher maintenance costs.
I don't really smell a conspiracy <_< but I do wonder what might have been. Quite often.
F5 Dave
21st June 2019, 07:27
Don't write that off too quickly . On another thread apparently the Obama administration were responsible for marxists popes, so maybe they, or the shape shifting lizard people killed off the blue smokers.
It's all making sense now:confused:
Best I get up and go earn some more taxes.
george formby
21st June 2019, 14:23
Don't write that off too quickly . On another thread apparently the Obama administration were responsible for marxists popes, so maybe they, or the shape shifting lizard people killed off the blue smokers.
It's all making sense now:confused:
Best I get up and go earn some more taxes.
David Icke blamed the shape shifting lizard people for the demise of the 2t and chocolate bars getting smaller in one of his podcasts. He's an authority on these matters so you must be correct.:wacko::)
It would be interesting to compare the emissions of carbie v FI 2t's. The KTM Enduro models come road legal in some countries and US states. Apparently.
F5 Dave
21st June 2019, 21:20
Well I've just had a piss off the balcony and it was quite glorious. Got some fair distance which isn't always apparent standing at the bowl.
Maybe this is more of an Instagram thing. Not sure how that works. Can I post a video?
lozz900
7th August 2019, 23:29
Old vehicles will get exemptions of some form - may be km limited or with the current government more likely you'll be taxed higher if you own a pre XX vehicle.
I think so too . A 40 buck rego for an old clunker is to good to be true..
OddDuck
10th August 2019, 11:26
Bikes appear to be smokier because you can see the smoke. Thing is, emissions aren't just the smoke you can see. For this reason, a 350cc bike emits less hydrocarbons than a 1600cc car despite appearing to be a lot worse.
I'm not sure about this, but it kind of makes sense. Any of you scientist types care to advise?
Well... it's not straightforward and it certainly isn't as simple as emissions are in proportion to engine size. There's emissions from unburnt fuel (vapour out of the tank or intakes), emissions from high combustion temperatures like nitrogen oxides, sulphur emissions from nasty fuel, and things like soot and particulates which is not good to breath in. Then there's the noise emissions, Harley rally anyone?
The bit that's a surprise is that you can get small engines that are dirty and large engines which are relatively clean. Small displacement two-strokes are among the worst because there's a lot of mixing of exhaust and inlet charges. High performance 4 strokes which use valve overlap and exhaust resonance will have a similar issue, it won't be as bad per cc but since there are so many more of them... But yeah, nothing's more obvious than a worn out diesel.
OddDuck
10th August 2019, 11:35
Just reading the posts above...
Fuel consumption is helped by ratio of cylinder volume to surface area. A high volume to low area means low radiation heat loss to head and piston. There's also inertial loss, pistons and conrods being thrown back and forth does require energy. So does bearing and ring friction. The most fuel efficient engine is large displacement, limited number of cylinders, low revving, square or undersquare bores. This is exactly not what racing competition, where it's all about HP / cc, has given us... thirsty engines that rev like hell and are all about throwing air and fuel through as fast as possible.
Two strokes: a really interesting type was opposed piston, uniflow, positively scavenged by blower. By the time you've done all that though you might as well make a 4 T. Would be really interesting to see what a modern, direct injection version of that could do.
Navy Boy
10th August 2019, 19:06
Just reading the posts above...
Fuel consumption is helped by ratio of cylinder volume to surface area. A high volume to low area means low radiation heat loss to head and piston. There's also inertial loss, pistons and conrods being thrown back and forth does require energy. So does bearing and ring friction. The most fuel efficient engine is large displacement, limited number of cylinders, low revving, square or undersquare bores. This is exactly not what racing competition, where it's all about HP / cc, has given us... thirsty engines that rev like hell and are all about throwing air and fuel through as fast as possible.
Two strokes: a really interesting type was opposed piston, uniflow, positively scavenged by blower. By the time you've done all that though you might as well make a 4 T. Would be really interesting to see what a modern, direct injection version of that could do.
In a way that explains why my H-D 48 does quite well on fuel, as does my wife's Sportster 883. The bore and stroke of the motor as well as it being low revving are all in its favour with regards to this particular argument. I guess that's partly the reason why the Honda 750NC motor does so well too.
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