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Post by hypojam on Dec 26, 2005 1:16:06 GMT
www.ebay.co.uk - Item number: 8023151003 Small electric turbo charger Probaly a load of crap but it appears to be able to fit our scoots ;D
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Post by Badobsession (the real one) on Dec 26, 2005 9:33:49 GMT
Yep looks a load of crap to me #rofl#
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Post by BillyGreen1973 on Dec 27, 2005 13:15:13 GMT
The theory is good, works like a supercharger, rather than a turbo, but like you said probably pants!
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Post by r08813 on Dec 27, 2005 18:05:35 GMT
No. They are crap - superchargers produce large volumes of air under pressure, electric motors cannot do this, they can provide more air, or some pressure, but not both. these produce a bit more air, but really disrupt the airflow.
Ask yourself why a supercharger, new, costs at least a grand. if they had cracked a method of doing this with an electric motor, all cars and bikes would be fitted with them.
don't waste your money, free flow air filter and re jet would have better results for less money.
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Post by Botanic on Dec 29, 2005 12:46:52 GMT
don't waste your money, free flow air filter and re jet would have better results for less money. Free air flow filters does not produce anything else but noise. Sometimes they even degrade the performance. Removing the restriction in the air box gives better results than a noisy free air flow filter.
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Post by r08813 on Dec 29, 2005 14:29:48 GMT
No, you missed the point "Free flow air filter AND Re jet", not one or the other, but both. Just air filter is going to weaken the mixture, just jet is going to not get enough air.
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Post by Botanic on Dec 30, 2005 15:35:28 GMT
No, you missed the point "Free flow air filter AND Re jet", not one or the other, but both. Just air filter is going to weaken the mixture, just jet is going to not get enough air. No, you missed my point. Free flow filter is useless whatsoever. Free filter is very bad with original jet. Free filter with bigger jet is not as good as original filter derestricted with bigger jet. Free air flow filter is for more sound ONLY!
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Post by hypojam on Dec 30, 2005 16:07:05 GMT
A freeflow filter must let air into the engine easier than the bike sucking air through the long pipes of the air box.
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Post by r08813 on Dec 30, 2005 17:42:51 GMT
Ah, botanic, I see what you are saying. My bike is not restricted (125cc) I think you are referring to restricted bikes.
The restriction is designed to stop the engine from revving too high and the gears from allowing the bike above a certain speed. This is mechanical, so ajusting the power of the engine would really be a waste of time( may accellerate a little quicker - but that's all)
Assuming the restriction is out of the way, the more air and fuel you can get into the engine, the more powerful it is (i.e. more torque and bhp etc). The easier it is to get the exhaust gases out, the better it is.
Engines require a mixture of air (preferably cold) and petrol to run. As long as the proportions are right the engine will run fine.
Standard air filters are made from paper (usually in a concertina format) and they trap dirt, whilst allowing the air to pass through. This dirt sticks to the paper and eventually blocks the holes the air passes through and restricts the air. This is bad, because, as the air cannot get into the engine as easily, the engine loses efficiency.
Free Flow air filters use a different principle, usually foam or metal mesh. The design of the material is such that the dirt does not stick in the same way and block the path for the air. Generally, they are set up to restrict the air much less than paper filters in the first place. So the airflow remains at it's peak for much longer.
That is why during a service, the paper air filter needs changing and a freeflow one doesn't.
The problem on bike engines with carburetters is that, the air, passing across the main jets collects a mist of petrol. The proportion of petrol to air needs to be at a specific value for the engine to be efficient. The movement of air across the jets causes a vacuum, which sucks the required petrol out of the jets (fuel injection is different). The size of the jet restricts how much petrol can come out and is set to create the correct proportion of fuel air. On a small engine such as a bike, If you have too much air going through, the jet becomes starved of fuel and the mixture is all wrong.
So a larger jet will cope with a greater airflow and allow more petrol to be available when the airflow demands it.
But, if there is more air and petrol, in the correct proportions, there is more power generated by the engine. There is a maximum before other mods are needed, but it's way above what the standard engine is capable of on normal air/fuel quantities.
It is easy to get wrong - too bigger jet means there is not enough air in the mixture, too smaller jet means that there is not enough petrol. The mixture must be correct.
The sound is caused by the extra air rushing in. (and no plastic surround to muffle it!!)
Where you may be a little confused is that, on a fuel injected engine, the computer adjusts the mixture on the basis of sensors matching the air flow and will often 'correct out' any extra air, to keep the engine within specified performance parameters.
So, as you can see, without question, A free flow air filter and a bigger jet suitable for it, definately increases the performance. And, it's a really cheap way of doing it too.
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Post by Botanic on Dec 30, 2005 19:28:08 GMT
Well, I had this same discussion before on another thread here somewhere. I am not trying to be a smartass or anything. I just try to help fellow scooterists to save money. How many reading this forum has a free air flow filter and a bigger main jet? I know that in theory the idea of a free air flow filter should be better than anything else. I have understood that it is hard to get hold of bigger main jets for our 50 cc scooters in the UK for some reason. I live in Sweden. Here it is not a problem to get bigger main jets. It seems to be a lot easier over here to get spare parts generally for these scooters. To me it seems strange that you don't have more over there. I visit two swedish forums and one finnish regurlary. Sometimes I even check out a good danish forum about these scooters. The general opinion over here in scandinavia is that a free air flow filter does nothing but sound. I have never owned such a filter, so I don't have personal experience about this subject. Most people get best performace by having a main jet that is either 0,90 mm or 0,88 mm. Bigger than that is no good, mostly just waste of fuel. The original main jet is slightly smaller than 0,88 mm. I haven't seen any good measurements of it. If you just change the main jet to a bigger one, there will not be enough air in the mixture. No matter how much you screw the air/fuel screw. What you can do in this situation is to get a free air flow filter or remove the air restriction. If you get a free air flow filter, you will get a lot of noise. Also all the people on the other forums seems to agree that the performance is not as good with the free air flow filter as the other method. In the air box, there is a small piece of plastic around the intake. This is the "air restriction" that I mentioned earlier. Usually if you remove this piece of plastic without changing the main jet, the mixture will get too thin. But in some rare cases it gets better. My scooter is one of these rare cases. I have read only of Baotian Sport -05's having this. It seems as if some scooters are wrongly adjusted from the factory. I don't know what makes it behave like this. Anyways, my guess is that the air channels in the carburetter and engine are too small to handle the extra air, or something like this. If you fit a 0,90 main jet and remove the air filter completely, you will probably get the same result as having the original filter without the air restrictor.
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Post by r08813 on Dec 31, 2005 0:01:07 GMT
Not sure where you get your facts from. If you run your scoot with no air filter - what ever size jet, you WILL ruin your carb and have to clean it. NEVER EVER suggest running with no filter (I wrecked a ford escort carb once by trying that!!)
Also, I have free flow filters fitted on my Lotus, which has carburettors, Dyno shows 8% increase in BHP at flywheel. Thats how I know it does work.
On the scooter, The GY6 engine fitted to your bike in it's standard form is designed to have more power, If you look at the honda or yamaha model it was licensed from, you will find the output was quite a bit higher when honda/yamaha made it originally (Chinese ones are tuned down slightly for emission reasons). It can easily cope with bigger jet and filter.
You may find that it isn't that noticeable though on a 50cc - they are not really that powerful that 10% would be a noticeable difference. On the 125 it is noticeable, but not much - still not really a powerful engine.
There are better ways of tuning, but Jet and free flow are the cheapest guaranteed to give results.
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Post by hypojam on Dec 31, 2005 0:28:31 GMT
I agree with r08813, everything i see and know shows that a freeflow filter is a better on pretty much any engine and generally gives more power when rejetted/fueled correctly
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Post by Badobsession (the real one) on Dec 31, 2005 0:44:55 GMT
My last sports bike was an R1 i fitted dynojet and k&n filter, and as a fully qaulified motorcycle mechanic since 1988 i do know how to fit them BUT you can hardly notice the difference on this bike so it wont do a lot for a 50. Save your money and buy a pint. If anyone tells you different they are either WRONG or a boy racer
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Post by Badobsession (the real one) on Dec 31, 2005 0:46:20 GMT
BEEN THERE DONE THAT #thumbs_up#
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Post by hypojam on Dec 31, 2005 0:51:08 GMT
Im a mechanic with a worthless NVQ, does that count for anything?
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Post by Botanic on Dec 31, 2005 1:08:40 GMT
To me it seems that you are comparing apples and oranges here.
I wrote that I know in theory there should be a difference. But according to all the people that I have read about that have been testing these filters together with a bigger main jet, there is no difference.
This is true. BUT it is even cheaper to just remove the air restrictor instead of buying the filter. Who wants the noise anyway, if you can get the same result without it?
I'm just trying to say that you should save your money.
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Post by Badobsession (the real one) on Dec 31, 2005 1:14:14 GMT
Im a mechanic with a worthless NVQ, does that count for anything? Why is it worthless??? must count for something #thumbs_up#
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Post by Badobsession (the real one) on Dec 31, 2005 1:27:34 GMT
From my experience of these type of filters they are more likely to make things worse than better regardless of what jets you put in These filters were designed a lot of years ago and have never changed, airboxes are there for a reason and not just to hold a filter. Look at valentino rossi's yamaha, what do you think he uses? a modern airbox? or a piece of junk which would be more suited to a boy racers 4 wheeled death trap fitted with a 3 foot diameter exhaust which obviously produces more power because of the noise it makes?
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