candle holder velocity stack

went to the swap meet today and found a cool stainless steel candle holder.

with a few easy mods, i made a velocity stack out of it.

still has the sponge in there, so it's not wide open.

it's a little louder, but so what.

here's some pics:

it's not a "true" velocity stack. it's still basically an air filter. haven't noticed a need to mess with the carb at all.

i didn't think about making a "how to" because it's so simple i didn't take pictures, but all i did to make it was... uh...

think of it like a metal shot glass. i just cut off the bottom, but left some metal on the sides, so i could bend the tabs over and drill holes to mount it.

then i took my old air filter apart, and used the plastic mounting ring and the sponge. i had to shave the ring down to match it up, you can see the black plastic in between the carb and the "stack."

i made another plastic ring out of some, well, plastic, and used that on the inside.

there's two small spacers inside that the sponge sits in, so it's not all compressed.

so you've got the carb, then the plastic ring, then the stack, the sponge and spacers, and the other plastic ring all sandwiched together.

the candle holder already had the cool flared out wings, which make it look like it was designed to wrap around the seat tube.

only problem i can forsee is if i park the bike next to some sprinklers, the sponge will fill up with water.

don't plan on riding in the rain much, and i've got a fender for puddles, so it should be fine.

it's mostly cosmetic. any performance gains by it breathing better than stock will probably be immeasurable. if i notice anything, i'll update this.

i'll probably add a piece of screen in there, and maybe re-do the element, but for now, it was just a lazy saturday project...

ok, so i rode about 50 miles today, almost all of it at WOT. there's a definite increase in top end power. probably gained a coupla miles per hour.

it cruises good in the low and mid range, but if you open it up off the line, it burbles and 4 strokes a bit till you get up to speed. not enough to bother me though, 'cause i do most of my riding winding it out.

gonna try spark plug gap and needle-clip settings (the basics) before i start messing with the jetting. i think i can fine tune it without having to drill and solder jets. might just be a matter of getting the filter breathing better.

the power and the fuel are there, i just gotta play around with it.

noise-wise, it's louder, and it amplifies the clangs and bangs of the motor, giving me that impending explosion feeling, but it's psychological, i hope.

i figured if it was gonna blow, it woulda done it today. one stretch of road i went at least 5 miles full throttle, without catching a red light. speeds approx 40mph.

i've got a stewart warner speedo coming, and after i calibrate it, i'll do some real speed runs, and post proof.

and damm, it sure looks cool compared to a crappy plastic box with oil and gas dripping out of it...

nope. i got a vintage bicycle speedo off ebay. it's a "cadet" model, made by S.W.

i don't think adapting a car speedo would be easy. you'd have to find one that's cable driven, and then somehow calibrate it for your wheel.

the bike speedos use a cable and a little drive gear that attaches to your front wheel. it's a pretty basic design, but it's prone to inaccuracy. they make one's with rpms, but with a little bit of math, you can tell it's not correct.

i've got a plan to calibrate mine, but i'll save that thread till i do it.

anyone notice how old this thread was?

i made that a long time ago. i still have it in a box somewhere. i used it on a backwards engine bike and it looked cool with the carb facing forward. and it worked pretty well. that bike needed more air for some reason...