Sadlsor
Site Supporter
- Joined
- Jan 15, 2020
- Messages
- 4,284
- Age
- 66
- Location
- Birmingham, Alabama
- Bike
- 2008 ST1300A
- STOC #
- 9065
Thank you.
Air inlet tubes - do I need them?
- Thread starter DONCZ
- Start date
We’re a peaceful bunch. Share lots of info, some fun and a safe space to learn and ask questions. That’s always a great way to behave in life. People don’t have to be an enemy just because they’re different.
Best wishes, really!
Best wishes, really!
amen, I know I have and probably will say something that offends. I am not intending to say get anyone off track and I am giving a preemptive apology.
"With all due respect, . . . " or "No offense intended, but . . . "
Sadlsor
Site Supporter
- Joined
- Jan 15, 2020
- Messages
- 4,284
- Age
- 66
- Location
- Birmingham, Alabama
- Bike
- 2008 ST1300A
- STOC #
- 9065
I know you think you understand what I said, but I'm not sure you understand that what I said is not what I meant.
Here’s some background info on how velocity stacks work:
Ninja 400 is currently hottest racing market with more new racers entering than any other. Really driving aftermarket to develop performance parts for this bike. Before & after dyno-charts showing results of various mods, including velocity stacks.
1. baseline bone-stock bike = 45.42hp
2. full-exhaust and dyno-tuning = 48.27hp, +6.27%
3. add velocity stacks and dyno-tuning = 52.67hp, +9.12%
From quoted articles, we see that stacks are optimised for specific frequency and maximises flow at specific RPM. In this case, velocity stacks are tuned for top-end power (with slight loss in mid-range torque).
Now it typically takes at least 10% increase in power for butt-dyno to registre differences. So yes, on ST, no discernable power differences can be felt with stacks removed. But it’s really there.
May need stopwatch to tell. That 9.12% HP increase or loss can be detected by stopwatch on track. It’s worth 0.7-0.9s per lap on most tracks. At end of race, that’s difference of several football pitches!!! Or difference between 5th or 2nd place!!!
Ninja 400 is currently hottest racing market with more new racers entering than any other. Really driving aftermarket to develop performance parts for this bike. Before & after dyno-charts showing results of various mods, including velocity stacks.
1. baseline bone-stock bike = 45.42hp
2. full-exhaust and dyno-tuning = 48.27hp, +6.27%
3. add velocity stacks and dyno-tuning = 52.67hp, +9.12%
From quoted articles, we see that stacks are optimised for specific frequency and maximises flow at specific RPM. In this case, velocity stacks are tuned for top-end power (with slight loss in mid-range torque).
Now it typically takes at least 10% increase in power for butt-dyno to registre differences. So yes, on ST, no discernable power differences can be felt with stacks removed. But it’s really there.
May need stopwatch to tell. That 9.12% HP increase or loss can be detected by stopwatch on track. It’s worth 0.7-0.9s per lap on most tracks. At end of race, that’s difference of several football pitches!!!
Or difference between 5th or 2nd place!!!
Last edited:
wjbertrand
Ventura Highway
Ridden normally on the road for a short distance, one might not notice the difference at first, but if you put the bike on a dyno, I’ll bet there’s measurably less power and likely some flat spots and drop outs along the power curve compared to with the intake cones in place. I’d bet there’s also a drop in MPGs, but that would take a longer ride to detect. Ridden on a backroad with some aggressive throttle inputs and exploring the entire RPM range, I have trouble believing any rider familiar with the bike wouldn’t notice the difference.
One should not consider a 30 mile ride without the intake cones in place as empirical evidence that Honda doesn’t know what they’re doing…
So mid-winter finds me crazy busy in the ski industry,,, but I was actually out for a short ride on my bike today. Between that short ride (dirty and salty dust on the roads),, and this threads topic being of personal interest to me,,, I gotta step in with a comment or 3. I made the above quote in 2017,,, but I have had some relevant actual experience with the intakes since then. I reported it in my thread on the "the Bazzaz bike", on which I made many mod's,,, including removing the upper velocity stacks (as a trial). The lower portion (about 1.25 tall) of each stack is still in place, and they need to be,, to secure the airbox. I have spent hours reading and watching test video's on the topic of velocity stacks,, and my opinion of the out come of their removal was that, it had to be a bad idea. But then I actually did it,, and tested it that way all last season. I tried it because I could easily un-try it by replacing the upper stacks. Longer story short,,, in combination with the other rather extensive intake and exhaust mod's that I made acceleration was definitely increased. I don't doubt that the removal is costing some fuel efficiency at faster cruise speeds. But, since I mostly ride the '04 locally,,, and tour longer distances on my '12,,, I do enjoy the extra torque that Blue STar has now,,, and won't be putting the upper stacks back on. Okay,, enough for now,,, flame away,,, I am off skiing for a week,,,, but I look forward to reading comments from members who have actually tried a mod',, and are not just offering untested opinions (like I did back in 2017),,, best, CAt'
I wasn't trying to make enemies i just took Umbridge at being told i wasn't in touch enough to notice how poorly my bike is running. My bike runs sweet at slow speed and when I twist the throttle it hitches up its skirt and gets some. On the m4 sitting at high speeds the bike purred all the way to Peterborough and back last month. There is a reason for them
Yeah its probably my riding style i dont ride aggresive there is never a time when im gunning it all the way through the gears. On a 300 mile ride to peterborough and back at triple digits it was golden but under very fast accelaration up through the gears it would probably be noticeable i just dont ride like that i tried it once on a group ride with some people doing some knarly moves but after one guy dropped back we went round a corner and hit roadworks he came in super hot and just managed to swerve 6 of us but nearly didnt.
Its interesting to hear from people who have tried different mods or ideas regardless of what they are. Im in a FB group and when the discussions come up about LED headlights you often get people saying LED headlights are crap its impossible to get the correct beam pattern they blind everyone etc Yet phillips sell LED headlights. Once put up a before and after picture of the beam pattern and was told i photoshopped it. LIke i have any idea how to photo shop anyway.
On paper they are there for a reason and as another person stated they may affect aggresive riding. To me the bike feels very quick on accelaration but i dont ride aggresively so cant comment on that. Maybe some people that do may remove them and then post up how that went. There are people that have been riding a ton longer with way more experence than me it would be interesting to get some more feedback onthe matter
Didn't mean to offend you by pointing out that you may not be aware or notice the difference in the way the bike ran without the snorkels in it.
I guess maybe I should have pointed out that you were not attentive enough to put all the parts back in
Last edited:
Well that changes everything....FB groups are so much higher skilled and trained than folks who are trained and skilled to work and build motorcycles
Yes, I have tested/ridden bikes with more modifications that you could imagine, including removing snorkels etc.
Had access to a dyno very close to where I worked as well.
And yes, I did notice a difference ridden hard, or on a track.
But then again, I notice tire pressure just by rolling a bike onto the table lift, that was down 10 psi and the guy riding the bike never noticed it.
I just pay attention to details....like Reacher says...Details matter.
In the 70's I used to build drag bikes with big HD engines in them, and used velocity stacks even
This forum is a wealth of information, and folks are very willing to share ideas and comments, relax a bit, share your thoughts and comments, and don't be so easily offended.
Cool. I don't really need your life story but If you have any hands on experience running the pan with and without funnels I would be interested on what you found the difference to be. Cheers
I totally agree about the velocity stacks. The early (50s and 60s and 70s} benefit was about the straightened air gave a better signal to the carbs for mixture control. For instance I built a 302 with some serious high RPM equipment on it which made low speed driving poor. What I did was put a 4 hole spacer underneath the carb that cleaned the slower air flow beneath that changed the air flow above.
On the fuel injected engines as well as the carbed engines the benefit of a "velocity" stack is in the name. More air with the mixture means better performance, If you look at the cam timing you will see that the overlap is designed for a charge of high speed fuel air mixture induction.
Cleaner airflow means better fuel air control which translates to better fuel air mixture which gives better throttle control with fewer emissions which gives better milage and a happier engine that lasts longer.
Love the word "which"
On the fuel injected engines as well as the carbed engines the benefit of a "velocity" stack is in the name. More air with the mixture means better performance, If you look at the cam timing you will see that the overlap is designed for a charge of high speed fuel air mixture induction.
Cleaner airflow means better fuel air control which translates to better fuel air mixture which gives better throttle control with fewer emissions which gives better milage and a happier engine that lasts longer.
Love the word "which"
"I'll get you my pretty!"
oh, wrong witch...
oh, wrong witch...
The engine was designed by Honda to use them.
The bikes run better in all aspects with them installed as intended.
It comes down to a choice I guess, operate the engine as it was designed and built by Honda, or trust some FB group or YouTube video’s and believe you know more than the research folks who build them.