KymcoForum.com
Scooters - Big Bore => Xciting 500 => Topic started by: guile on March 08, 2010, 07:20:12 PM
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As there is no perfromance airfilter on the (after-)market available, I decided to test if driving without the airfilter would change anything in the performance of the engine. Reason is that with WOT (wide open throttle) the scooter seems to be holding back. So I uninstalled the airfilter and put a nylon stocking of my wife there to prevent damaging the engine. I warmed up the engine and I rode for about 5 km with WOT.
The results are positive:
- no more gap, WOT is WOT;
- acceleration response is better (more hp???);
- heavier sounding (of course).
The results of the test would suggest that an high performance airfilter will definately improve performance. The diameter of the airintake-side of the carb is 55 mm. As there is not much room to install an airfilter I checked http://www.knfilters.com/search/univcone.aspx (http://www.knfilters.com/search/univcone.aspx) to see if there is an K&N airfilter that would fit. Maybe the RC-2340...
What spark is needed after installing a K&N filter and which jets does one need to change (and where on the carb)?
Finally, would installing an airfilter so close to the tire where all the dirt comes from, be a problem?
I would appreciate some thoughts and suggestions on the matter.
Groet,
Gijs
The Netherlands
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..well, i would think that your experiment indicates that for whatever reason, your fuel mixture with the stock airbox is a bit rich...
..is your scoot new?..
..what is the condition of your stock filter element..may need cleaning or replacing...
peace
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..well, i would think that your experiment indicates that for whatever reason, your fuel mixture with the stock airbox is a bit rich...
..is your scoot new?..
..what is the condition of your stock filter element..may need cleaning or replacing...
My scoot has 9000 km on it. I bought it second hand. The filter is clean; looks almost new.
Tell me, how can I adjust it. Adjusting the jet that is sticking out from under the carb makes no difference (after full warm up and reving stationary at about 2000).
Thanks.
Gijs
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..i'm not personally familiar with the X500..however, the screw on the carb should only adjust your idle, and just off idle mixture..
..to get to the jet that regulates WOT, you gotta remove and dis-assemble your carburetor..the "bowl" on the bottom is where you will be able to access the main jet..
..the main jet is directly inline with the needle...a smaller diameter jet there would reduce the amount of fuel that gets diffused into the airstream, by the needle...
..however, if you can increase your performance by installing a high-flo air filter, then that would be the easiest way to go...you just want to be sure that the fuel mixture does not become too "lean"...
..hang out here, and i'm sure that some ppl with more experience than i will offer some more advice..
peace
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Thanks Wordslinger for your replies.
If I were to install a high-flo air filter, does this mean you have to install another mainjet and if so which one/what size and brand?
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What Make is the Carb? WE can help you find the jets for it.
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This should be it:
Type CVK
Main jet NO. 98
Venturi dia. φ36 mm (φ1.44 in)
Throttle type PISTON
Carburetor identification number 15F8 SD8
Size of bore (mm) Ø36
Main jet #108
Slow jet #38
Idle speed 1400±100
Pilot screw opening 3½ ± ½ turns out
Fuel pump flow (at 12V) 370 ml (12.6 US oz, 13 lmp oz)/min
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That's a Keihin carb. Bike bandit has a kit for them. http://www.bikebandit.com/keihin-main-jet-kit (http://www.bikebandit.com/keihin-main-jet-kit) I have dealt w/ them 4 times, and have been very happy. They will spam you to death tho. I think the kit has 3 or 6 jets depending on what you want. I'm sure you can find them cheaper w/ a little looking around.
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did your wife notice one of her stockings went missing?...on no account tell her where it went...you are some hero using the wifes nylons for an air filter...you could substitute fishnet type and open up the flow even more ;D
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I cut out the paper baffles in the center of the OEM air filter and inserted Unifoam as the filter. Works well.
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Great guys. What sizes of jets do I need? There are many kits around, so choosing one is difficult.
Bongoman, where did you get this 'unifoam'. Here in The Netherlands it's not for sale...
The wife says: :-*
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For JUST a filter I would pick up #110, 112, and 114. That will get you set up. Pick up 2-3 new plugs as well. Maybe 1 step colder on one of them. Especially if you use regular pump gas.
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Just a thought, wouldn't drilling holes in the airbox-intake be a way to provide more airflow?
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...it warms my heart to see some of you X500 guys talking about mods.......
:D
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Opening the box up w/ several 1" holes is the Poor Mans way of doing it. The biggest restriction is the water baffels, then the element, then the plumbing to the carb itself. The 500 has a fairly straight shot to the carb from the box. so the plumbing is ok. Open the box, add the unifoam, and you will get some of the pep an aftermarket set up will deliver. My stock air box looks like it was used for target practice! The K&N looks better, works better, and will last for several years. (2+ so far on mine)
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Bongoman,
you talk about 'unifoam' you put in the original filter. As there is nothing to hold the foam after the paper is cut out, how does the foam stay stuck?
Btw, unifoam is not known here in Holland.
Could you make a photo of the filter?
Thanks.
Groet,
Gijs
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I found this : http://www.ibmwr.org/otech/airfilter.html (http://www.ibmwr.org/otech/airfilter.html)
It's fairly informative, although I don't know quite what to make of it all.
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I'll post a photo soon.
After I cut the carboard baffles out, I stuffed the unifoam in tight around the edges. There is a sort of lip. Since the engine sucks the Unifoam down anyway, I have had no problem. And it's cheap. $7 bought enough for two filters.
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Thanks. Let the modding begin! ;D
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Does anyone have any photos of the KN filter in use in an Xciting or a P250. I was thinking I would like to do this.
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Kymco 250 test drive and upgrades (http://www.youtube.com/watch?v=8iTt6o68sc4&feature=related#normal) This is one of those Martin Racing posts. I didn't get to watch it but it was labeled Test ride and up grades.
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Moded my airfilter, removed the cardboard element and replaced it with the racing air filters for cars.