icedragon Posted May 2, 2012 Posted May 2, 2012 Im just after some advice on Air Filters. All i can find is conflicting arguments when looking up replacement air filters. Some people say a new filter is a MUST DO Some people say dont bother its a waste of time and causes tons of mixture problems and only eats more fuel and makes a noise. Ta people
Moderator Cynic Posted May 2, 2012 Moderator Posted May 2, 2012 If your fitting it to a sub 10 second quarter mile bike fine, otherwise your right mixture etc goes to pot. Years back i had a Suzuki tuned by TTS (google em) and they will not without specific instruction from the owner remove the stock airbox. Cos of the hassle it causes.
icedragon Posted May 2, 2012 Author Posted May 2, 2012 Ok I feel silly now. Obviously it's a bike that does quarter of a mile in 10 seconds. It's a tzr50 so that's a noooo
2 Wheels Posted May 2, 2012 Posted May 2, 2012 Im not a fan of them either. Its a 50cc bike,,,,, youll be ringing its neck to try an get her to go fast,,,,,,,if you dont set up cone filter/ carb propperly then when your screaming her down the road the bike will run lean,,,,get hot,,,burn a hole in piston head,,,,,then she will have a slight heartatack,,,,, lie down and rest,,,,,,,, she then wont get up again till you take her in your arms to your garage,,,,,, it is here that you will have to do some surgery on her,,,,,, dont worry though, she will live to ride another day, but it will be costly
Morpheuz Posted May 2, 2012 Posted May 2, 2012 Recently did up a mates 50cc, carbed 50cc bikes are easy, if you bang a cone filter on, its only worth it, if you make sure there are no restriction washers, (making the intake hole smaller). If its all open from the carb to the engine, then a cone will help, only if you up the fuel slightly, if not, it will run hotter and may stumble at times, and have little power increase. To up the fuel, its the jets in the carb, you may already know this, the idle mixture may need upping, it will be a screw located in the casing of the carb, outward turn, will keep it ticking over and starting fine. Then the main jet, up about 5-10 sizes, you'll have to check different sizes and see which is best, that should richen up midrange slightly too. 50cc's spend most of their time at wide open throttle due to their small power output, thats where the main jet is flowing, on any engine, wide open throttle shouldn't be lean.
icedragon Posted May 4, 2012 Author Posted May 4, 2012 Ok well my cone air filter came at the same time as my technigas Exhaust. I fitted them both together and the bike run really well (besides the noise out the cone). I decided the noise was too much and fitted the old air box back. Now the bike splutters with anything less that full throttle. There are 2 screws on the carb. One Definatly adjusts the idling but im not sure of its a mixture one or not the is a second screw next to it but not sure what it is. As standered they Usualy have a #88 main jet but mine already had a #125 fitted. just to clarify. Standered exhaust with standered airbox the bike Run fine. Performance exhaust and cone filter the bike run far better. Porformance exhaust and standered box the bike runs really poor. I suppose it's obvious by that the bike needs more air or less fuel but can this be done by a mixture screw or a lower jet.
Ryan09 Posted May 4, 2012 Posted May 4, 2012 Youll probably have to up jet the carb to get it running properly with the exhaust, if it runs better with the cone filter why not leave it on? All youre hearing is the induction noise.
icedragon Posted May 4, 2012 Author Posted May 4, 2012 I think I will for now. I have a 90cc bore kit to fit soon. Just need the time to do it. I wanted it running right first instead of doing everything at once.
Ryan09 Posted May 5, 2012 Posted May 5, 2012 Id still recomend checking your spark plug to make sure its running right as it will probably need up jetting.
Morpheuz Posted May 6, 2012 Posted May 6, 2012 Bike wants to take in as much as its kicking out, and it cant with a closed intake, with the cone, it took in what it wanted, then kicked it out, with the bigger jet already in, it loved it. now with the throttle fully open, youre giving it all the air it can get, which is taking it closer to what the cone did, when closing it, the bike still kicks the waste out freely, but cant make up it with the increased intake. Open exhausts, and closed box intake, with bigger jet, maybe affectine the needle too, so could be rich depending on your setup at midrange. If a cone improves it, it suggests too rich. You'd be better off adding a free flow air filter, or lowering the jet and/or closing up exhausts. Simply adding a cone would probs be easier, then just make sure jets are set right. When you alter parts of the engine flow, jetting has to be set up right, or these problems happen. The 2 screws on the carb is one, for idle speed, its on the side and it pushes against a slant on the slide in the carb, same as opening the throttle slightly. The second, (upside down for most, underneath) alters the fuel, for idle speed only.
Moderator drewpy Posted May 6, 2012 Moderator Posted May 6, 2012 with 90cc, you'll need to go pre mix as the oil pump can't handle the flow for the extra cc's
icedragon Posted May 7, 2012 Author Posted May 7, 2012 Morpheus. If both screws do the same what's the point in having 2 then. Drewpy What's the mixture ratio please
Moderator drewpy Posted May 7, 2012 Moderator Posted May 7, 2012 depends what oil you use; 40 - 50 : 1 for synth
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