More air !
- Thread starter Gulu73
- Start date
This is going to sound totally crazy coming from me (& all I've said in the past), But I recently totally hot rodded one of my bikes & couldn't figure out why it wasn't going any faster!?!?, So I took off the K&N style filter & ran it without a filter & the thing was stoopid fast!!!
So I did several experiments with other filters (including a stock filter) & I concluded that a stock filter with large holes drilled in the face was the best for air flow!!!
Everyone on the last LA night ride knows how fast my blue boardie was!!!
Here's a pic of how it is now with a stock (drilled) air filter!!!
So I did several experiments with other filters (including a stock filter) & I concluded that a stock filter with large holes drilled in the face was the best for air flow!!!
Everyone on the last LA night ride knows how fast my blue boardie was!!!
Here's a pic of how it is now with a stock (drilled) air filter!!!
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first thing is to check is your needle setting and fuel ratio.
move the clip up on the needle to lean it out, but check your plug after a run to make sure it's not too lean.
move the clip up on the needle to lean it out, but check your plug after a run to make sure it's not too lean.
holes in the filter face does indeed help a little bit (While making it more prone to dirt), But proper fuel mix is set by the clip on the needle in the carb.
I did much the same to my first bike. Multiple holes I cut the whole back end open of the plastic filter housing. . It was because of frame clearance tho. What I did was stretch tight over the outside 4 plies of black Nylon stocking [panty hose] Just neatly plastic cable tied. It worked great as a filter medium. I had the fastest bike out of every one here where I live.
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A problem with some of the cloth-pleated K&N style filters is they are made in such a way it blocks the air getting in. The "W" fold when it's formed in a circle can block itself off from air, instead of a nice "W" it looks more like "\l/" with the inside bottoms of the "W" closing off flow. Pinching the top off for a tapered cone makes matters worse. The older CNS aircleaners are really bad about that.
American Power Sports has a filter that's under $13(not including shipping) K&N's the same size are $30+. The pleats are shallower and spread out more so when the filter material is formed round the pleats stay open.
APS shows 2 filters to fit the CNS carb with it's 1 1/4" opening. They are 3"x4" and 3"x5". The filter is set on a 20 degree angle from the inlet. Still not enough cleaning for you? You can add a foam pre-filter for around $3. The prefilter should help to dampen the carb intake moan somewhat, too.
I see that the OP has a stock filter. APS has adapters for adding filters to carbs without a mounting flange. APS shows an adapter for a Tillotson carb with a screw spaceing of 1.370. A rat tail file can slot the holes the 1/8th" or so needed to bolt this up. These adapters will fit the filters with a 2 1/2" opening. Just make sure you give them all the part number they need to send you the right parts
American Power Sports has a filter that's under $13(not including shipping) K&N's the same size are $30+. The pleats are shallower and spread out more so when the filter material is formed round the pleats stay open.
APS shows 2 filters to fit the CNS carb with it's 1 1/4" opening. They are 3"x4" and 3"x5". The filter is set on a 20 degree angle from the inlet. Still not enough cleaning for you? You can add a foam pre-filter for around $3. The prefilter should help to dampen the carb intake moan somewhat, too.
I see that the OP has a stock filter. APS has adapters for adding filters to carbs without a mounting flange. APS shows an adapter for a Tillotson carb with a screw spaceing of 1.370. A rat tail file can slot the holes the 1/8th" or so needed to bolt this up. These adapters will fit the filters with a 2 1/2" opening. Just make sure you give them all the part number they need to send you the right parts
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with my first engine i just used half a spray paint cap to scoop air in to the carb at higher speeds. it made a huge difference even better than running without a filter... would be bad if you were on a dirt road i guess... oh and make sure your design is strong after i did that i broke a motor mount from extra power/speed not sure which
Do this!This is going to sound totally crazy coming from me (& all I've said in the past), But I recently totally hot rodded one of my bikes & couldn't figure out why it wasn't going any faster!?!?, So I took off the K&N style filter & ran it without a filter & the thing was stoopid fast!!!
So I did several experiments with other filters (including a stock filter) & I concluded that a stock filter with large holes drilled in the face was the best for air flow!!!
Everyone on the last LA night ride knows how fast my blue boardie was!!!
Here's a pic of how it is now with a stock (drilled) air filter!!!
Match up the shape of your intake manifold to your intake port, Make sure there aren't any casting flaws or other gnarly slag in any of your engine's porting (Check those transfer port ceilings! They must be smooth!) Match and polish your exhaust port and exhaust bracket's opening. Make Certain all your gaskets are relieved to match your ports as well.
After that, make Certain that at Bottom dead center (BDC) your piston's crown comes down level with the exhaust port's floor. Mine was .25" too high, I had to make a spacer to raise the cylinder. Now check Top Dead Center at your intake port. You're probably going to see some piston skirt blocking your intake. Scribe a line on the piston the shape of the intake port at TDC, and releive that with a dremel or file. While you're at it, match your piston skirt to the transfer port openings. This all requires removal of the piston.
Now that you've fixed the Real reasons your engine isn't breathing, You can look at your air filter. the Good news is this sort of performance improvment only costs money if you ruin parts. And even then, it only costs the cost of stock parts!
After that, make Certain that at Bottom dead center (BDC) your piston's crown comes down level with the exhaust port's floor. Mine was .25" too high, I had to make a spacer to raise the cylinder. Now check Top Dead Center at your intake port. You're probably going to see some piston skirt blocking your intake. Scribe a line on the piston the shape of the intake port at TDC, and releive that with a dremel or file. While you're at it, match your piston skirt to the transfer port openings. This all requires removal of the piston.
Now that you've fixed the Real reasons your engine isn't breathing, You can look at your air filter. the Good news is this sort of performance improvment only costs money if you ruin parts. And even then, it only costs the cost of stock parts!
Allow me to put it this way: I had to cut a spacer from 3/16" aluminum plate by drilling around an outline, then chiseling out the web between the holes. That, and two copper foil gaskets later and the piston just bottoms out at the floor of the exhaust port now. There's a high compression head on order to correct the compression ratio, since now I have far too much headspace.
The motor I have is an old bikeberry 58CC, probably an off brand starfire or something like. It's decidedly first gen.
The motor I have is an old bikeberry 58CC, probably an off brand starfire or something like. It's decidedly first gen.
no inline fuel filter ? and what is that white thing connected to your cdi ?This is going to sound totally crazy coming from me (& all I've said in the past), But I recently totally hot rodded one of my bikes & couldn't figure out why it wasn't going any faster!?!?, So I took off the K&N style filter & ran it without a filter & the thing was stoopid fast!!!
So I did several experiments with other filters (including a stock filter) & I concluded that a stock filter with large holes drilled in the face was the best for air flow!!!
Everyone on the last LA night ride knows how fast my blue boardie was!!!
Here's a pic of how it is now with a stock (drilled) air filter!!!
That's not the stock CDI, it came from a member in Ecuador and is a high performance upgrade. He makes the electronic box and then you get an ignition coil from a honda or something like that on ebay to use with the box. That's what "that white thing" is
lol I must sound like a complete beginner ( which I am ) with lingo like that haha ... thanks for the response ... do you know which member in Ecuador and if he still makes and sells them ? also how does it increase performance ?That's not the stock CDI, it came from a member in Ecuador and is a high performance upgrade. He makes the electronic box and then you get an ignition coil from a honda or something like that on ebay to use with the box. That's what "that white thing" is