Author Topic: Who has pics of velocity stacks (Read 7382 times)

aussie · « **on:** May 11, 2009, 02:49:12 AM »

Anybody have some pictures of velocity stacks on there bike?. More importantly what did you use to hold them on?.

hymodyne · « **Reply #1 on:** May 11, 2009, 04:00:07 AM »

most come with their own clamps.
hym

aussie · « **Reply #2 on:** May 11, 2009, 04:03:23 AM »

Quote from: 1jbooher on May 11, 2009, 04:01:29 AM

S.S. clamps hold on my Velocity stacks

Would you have a photo available, and what size did you get for your 550?

Retro Rocket · « **Reply #3 on:** May 11, 2009, 04:07:56 AM »

Hi Aussie, I have a set of sandcast CR31's but they have screw on stacks so that will be totally useless to you....

Mick

scunny · « **Reply #4 on:** May 11, 2009, 12:58:19 PM »

stainless clamps on my old 500, sorry about bad pic quality

martino1972 · « **Reply #5 on:** May 11, 2009, 03:15:13 PM »

is sand and dirt not a problem with those things..

Toxic · « **Reply #6 on:** May 11, 2009, 03:24:17 PM »

Short answer ... yes.

Ride one at wide open, reach down with your hand and feel the amount of air getting sucked in... it's astonishing.

mcuozzo · « **Reply #7 on:** May 11, 2009, 03:28:47 PM »

If you run them wide open - Yeah, dirt etc. is a problem.

It's possible to have filter material across the opening though. No difference than having an airbox then is it???

If you search around the net there are plenty of pics (cars and motorcycles) where the stacks have filters on/across them. I'm on my way out to dinner, I'll search and find some later (if no one beats me to it).

Matt

mystic_1 · « **Reply #8 on:** May 11, 2009, 08:59:30 PM »

Quote from: mcuozzo on May 11, 2009, 03:28:47 PM

It's possible to have filter material across the opening though. No difference than having an airbox then is it???

Actually it is, and having anything in front of the stacks sorta defeats their purpose (excluding cosmetics).

mystic_1

754 · « **Reply #9 on:** May 11, 2009, 10:49:07 PM »

I had trouble finding aircleaner foam on my 836.. so I ran them open for a few years, even on the dirt oval..

And EVERONE told me it was bad for my motor and would wear it out, and that THEY would NEVER do that to theirs..

and I got to admit, THEY were right...

That damn 836 motor I beat on so many times, only lasted 25 years.. when it really should have gone 27 years...

martino1972 · « **Reply #10 on:** May 11, 2009, 10:52:56 PM »

Quote from: 754 on May 11, 2009, 10:49:07 PM

I had trouble finding aircleaner foam on my 836.. so I ran them open for a few years, even on the dirt oval..

And EVERONE told me it was bad for my motor and would wear it out, and that THEY would NEVER do that to theirs..

and I got to admit, THEY were right...

That damn 836 motor I beat on so many times, only lasted 25 years.. when it really should have gone 27 years...

Well,I gave it some thought,like I do believe it will suck in dust etc... but really,how much harmful sand etc. is there on a paved road...

and even if it shortens it's life by a few years,still nothing to really worrie about.....
I checked my airfilter after a year of riding,it's still clean,hardly anything came out of it when I blew it out....

heffay · « **Reply #11 on:** May 11, 2009, 10:59:32 PM »

here's my theory... if you're willing to run the risk of stacks... you're probably willing to run the risk of having to clean your carbs.

damage? no, not normally?
more periodic checking and cleaning? yes, possibly.

lordmoonpie · « **Reply #12 on:** May 12, 2009, 05:26:07 AM »

+1 Heffay

I run open velocity stacks on my race bikes - OK so mileage is less but the tracks are no cleaner than the roads (Tonfanau even has sheep sh1t to contend with :-)) and I've run them like this for 8 years with no issues.

fishhead · « **Reply #13 on:** May 12, 2009, 06:23:24 AM »

I made a set for my Kawasaki Z-1 900 carbs. I needed a place to mount the nozzles for the aftermarket accelerator pump nozzles (the carb bells were thin and I needed a more secure mounting point for the nozzles) and the velocity stack were machined to have pod filters mounted to the ends. They worked fine on paper and on the bench, but when mounted on the bike, the accelerator pump arm hit the cam chain adjuster and couldnt be used anyhow (on the Z1, they fit on the CB 750, but filters wouldnt fit on the stacks).
FBTFFOF!!!!
(Foiled By The Fickle Finger Of Fate)

ryder60 · « **Reply #14 on:** May 12, 2009, 09:23:18 PM »

How long are the stacks? It looks to me that anything longer than 3 inches will contact the frame of my 550. Where would you get them?

mystic_1 · « **Reply #15 on:** May 13, 2009, 08:51:36 AM »

Quote from: fishhead on May 12, 2009, 06:23:24 AM

I made a set for my Kawasaki Z-1 900 carbs. I needed a place to mount the nozzles for the aftermarket accelerator pump nozzles (the carb bells were thin and I needed a more secure mounting point for the nozzles) and the velocity stack were machined to have pod filters mounted to the ends.

Heh, well now you're just plain cheating, adding extra fuel circuits!

I love it!

Too bad about the interference issues. Did you ever run them on a 750, or just test fit them, and if so how'd they run?

mystic_1

fishhead · « **Reply #16 on:** May 13, 2009, 04:02:06 PM »

Quote from: mystic_1 on May 13, 2009, 08:51:36 AM

Quote from: fishhead on May 12, 2009, 06:23:24 AM
I made a set for my Kawasaki Z-1 900 carbs. I needed a place to mount the nozzles for the aftermarket accelerator pump nozzles (the carb bells were thin and I needed a more secure mounting point for the nozzles) and the velocity stack were machined to have pod filters mounted to the ends.

Heh, well now you're just plain cheating, adding extra fuel circuits!

I love it!

Too bad about the interference issues. Did you ever run them on a 750, or just test fit them, and if so how'd they run?

mystic_1

I test fit them but never ran those carbs on the 750. I ended up pulling the accel pump mechanism off those carbs and selling the carbs. I'll probably end up putting the accel pump on some other carbs in the future.
I did run the later Mikuni VM 28 SS Accel pump carbs for a short while on my 750, but went to Webers (with velocity stacks) instead .
The later 28's ran real good but don't compare to the Webers (ask 754

)

aussie · « **Reply #17 on:** May 14, 2009, 01:19:06 AM »

You gotta be lucky sometimes

, the dyno boys had this set of factory Honda HRC tuneable velocity stacks laying around and were a peferct fit. They slide in and out on them self.

moham · « **Reply #18 on:** May 14, 2009, 06:21:59 AM »

Quote from: 1jbooher on May 13, 2009, 03:35:01 PM

Here are the NOS stacks I got from Cycle exchange

Are those from www.cyclexchange.net ? What did you pay? I didn't see them listed on their site...

Hondell · « **Reply #19 on:** September 17, 2009, 12:16:08 PM »

Here's a set I made with our rapid prototyper.

moham · « **Reply #20 on:** September 17, 2009, 04:32:40 PM »

Quote from: Hondell on September 17, 2009, 12:16:08 PM

Here's a set I made with our rapid prototyper.

Hondell, what's the story with these? For what carbs, etc?

davesprinkle · « **Reply #21 on:** September 19, 2009, 04:08:08 PM »

CR26 with stacks cut from billet.

bwaller · « **Reply #22 on:** September 19, 2009, 05:21:36 PM »

Nice work Dave and it's obvious you know your stuff, but I gotta ask, have you done any dialing in on a dyno to see if that length is optimal for a performance increase?

davesprinkle · « **Reply #23 on:** September 19, 2009, 05:34:03 PM »

Quote from: bwaller on September 19, 2009, 05:21:36 PM

Nice work Dave and it's obvious you know your stuff, but I gotta ask, have you done any dialing in on a dyno to see if that length is optimal for a performance increase?

Thanks for the kind words, BW. Nope, didn't iterate on stack length.

turboguzzi · « **Reply #24 on:** September 19, 2009, 06:03:53 PM »

Quote from: davesprinkle on September 19, 2009, 05:34:03 PM

Quote from: bwaller on September 19, 2009, 05:21:36 PM
Nice work Dave and it's obvious you know your stuff, but I gotta ask, have you done any dialing in on a dyno to see if that length is optimal for a performance increase?
Thanks for the kind words, BW. Nope, didn't iterate on stack length.

nice indeed Dave, cost involved?

I went through some heavy pain due to the effect of untried velocity stacks, but those were put on 26VM which originally hava a big step in the bore.

whoever wants is invited into this stacks thread in the perf forum

http://forums.sohc4.net/index.php?topic=58658.0

to the rest of you guys, I have to wnder about the shapes and sharp edges in some of the stacks you posted. Gordon Blair claims that this is the single most important factor, taper is only secondary ....

http://www.profblairandassociates.com/pdfs/RET_Bellmouth_Sept.pdf

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Author Topic: Who has pics of velocity stacks (Read 7382 times)