Topic: Velocity stacks????

[Matt Hubbell]

My stacks from Japan.

[lucky]

the site says they come with screens, so would these be safe enough to run on a near daily driver??  or should i stick with looking for some pods?

i had an idea that if you could attach a filter material to the outside of the screen it would help out a lot more for filtration and wouldn't get sucked into the engine...

No problem. Filter material cut and fitted on the outside of the screens on my 1978 CB750 with Steel Dragon velocity stacks.
You cannot see the filter because it is inside the stack.

BTW the screen goes over the carb then the velocity stack goes over the screen. Make sure one of the set screws faces straight down so that the other two screws end up in a position on the carb outlet that is strong.
If you have one of the three set screws facing straight up that is the weakest area and you can dent the rim of the carb outlet if you tighten the set screw too much.
The set screws just need to be tightened until they touch and thats it. There is a raised lip on the carb outlet that will prevent the stack from coming off. Also make sure to put Locktite on all of the set screws.

[lucky]

What about just cutting some foam out of another aircleaner and putting it inside the stack to use as a filter?

Yes I did exactly that. No problems.
Filter cannot get sucked in, because the screen is in place.

BTW...A pod filter will have the same jetting requirements as a POD, because a pod filter has almost NO restriction of the air. If you do not believe me take a pod filter and breath in and out of it. See what I mean?

[lucky]

My stacks from Japan.

Very fine look'n bike!!

[lucky]

Last week, just before i put the bike away for the season i put on the stacks to see what kind of difference they make.

Bike is tuned for pods and runs excellent.  Threw on the stacks and it immediately felt lean.  I wonder how much more fuel i would need and how much more power it would make?  There seems to be some potential there.  On the other hand i spent the summer tuning for the pods.... , don't really want to go thru that again for a while.

PODS have almost NO air restriction.
Take a POD and breath in and out of it. See what I mean?

[TwoTired]

Last week, just before i put the bike away for the season i put on the stacks to see what kind of difference they make.

Bike is tuned for pods and runs excellent.  Threw on the stacks and it immediately felt lean.  I wonder how much more fuel i would need and how much more power it would make?  There seems to be some potential there.  On the other hand i spent the summer tuning for the pods.... , don't really want to go thru that again for a while.

PODS have almost NO air restriction.
Take a POD and breath in and out of it. See what I mean?

When you are able to breathe at 500 CFM, that test will have some meaning.  Any filter membrane has restriction and a pressure drop across it.  The magnitudes are related to velocity.

[Tintop]

What about just cutting some foam out of another aircleaner and putting it inside the stack to use as a filter?

Yes I did exactly that. No problems.
Filter cannot get sucked in, because the screen is in place.

BTW...A pod filter will have the same jetting requirements as a POD, because a pod filter has almost NO restriction of the air. If you do not believe me take a pod filter and breath in and out of it. See what I mean?

I'm sure they look good, but with filter material stuffed down them they are no longer stacks.  Just x4 seperate filters.

[Sam Green Racing]

Listen to the last two posters, are you looking for performance or cool.
I know a person that has the best of both worlds, he has an ARD mag fitted with an electronic ignition hidden away underneath, It's cool and performs as well the stacks with fillters will kill them performance wise and anyone that knows what they are talking about will know that you are bulling them, it's hard to hide fillters.

Sam

[Sam Green Racing]

I'll have to read all of this thread tomorrow, seems the starter has not been involved since page two.

Sam.

[lucky]

just order some Honda CB750 Bell velocity stacks from Speed Dragon good customer service so far let's see how the stack shine and fit.

That was Steel Dragon.

[lucky]

What about just cutting some foam out of another aircleaner and putting it inside the stack to use as a filter?

Yes I did exactly that. No problems.
Filter cannot get sucked in, because the screen is in place.

BTW...A pod filter will have the same jetting requirements as a POD, because a pod filter has almost NO restriction of the air. If you do not believe me take a pod filter and breath in and out of it. See what I mean?

I'm sure they look good, but with filter material stuffed down them they are no longer stacks.  Just x4 seperate filters.

Yes...but they still look like stacks. The bike runs good and puts out 50 HP.

[cwchan]

PODS have almost NO air restriction.
Take a POD and breath in and out of it. See what I mean?

When you are able to breathe at 500 CFM, that test will have some meaning.  Any filter membrane has restriction and a pressure drop across it.  The magnitudes are related to velocity.

2X.  I was going to comment but i thought lucky was being sarcastic

[TS250]

What about just cutting some foam out of another aircleaner and putting it inside the stack to use as a filter?

Yes I did exactly that. No problems.
Filter cannot get sucked in, because the screen is in place.

BTW...A pod filter will have the same jetting requirements as a POD, because a pod filter has almost NO restriction of the air. If you do not believe me take a pod filter and breath in and out of it. See what I mean?

I'm sure they look good, but with filter material stuffed down them they are no longer stacks.  Just x4 seperate filters.

Yes...but they still look like stacks. The bike runs good and puts out 50 HP.

Huh???  Just for kicks, I gently inserted (read: didn't stuff/cram/wad-up) some filter foam into the stacks on my 550.  The carbs are jetted for the stacks, and with the foam, ran horribly above 3000rpm.  Imagine that, the foam actually does significantly restrict!