carb air flow technical question

[Agemax]

ok, so i have standard VM26's with stage 3 dynojets and bellmouths on a 1085cc motor. i now have a stainless plate covering the gap in the frame where the airbox used to fit. see old photo with pods, but plate is the same.



question is bearing in mind my knees/boots will be covering up most of the side area behind the carbs, will the plate assist in flowing air into the carbs as i am moving forward or will it disrupt the air flow, or should i remove the plate?
technical advise/ criticism accepted thanks

[hampshirehog]

You won't be able to notice any difference. You won't get any ram air effect or anything like that. I suspect that if you got up to maybe 100+ mph then pulled the clutch in and let the bike tickover you might notice some fluctuating.

[Big T]

That air is so turbulent from the front of your bike that it really won't make a difference

[TheCafeKid]

Age mate if ya look at some photos of old race bikes you may see a similar contraption used. The ones I've seen actually radius around the carbs and for a sort of "side-less" air box. I asked Dave who used to build old race bikes in SA and he said they're used to restrict turbulence in the air being sucked into the bellmouths to assist in creating a nice smooth flow.
This all goes back to the merits of polishing your intake runners. On a race bike it's done to acheive smooth flow. On a street bike, being as they're generally not run at the ragged edge of RPMs the imperfections in the runners aid in atomizing the air fuel mixture. So a polished head on a street bike might make for a odd throttle response. Flat down low and then peaky high up maybe.
I dont think you'll find any difference in your set up, although I'd maybe watch and see what your plugs look like as you go on. That'll be a tell, if you've set your carbs up similarly, whether the inner two arent getting as much air as the outers, but I doubt it.

[tkent02]

I think you should cut a clear (or blue) window in the side of the Venturi so you can see the airflow.

[Agemax]

I think you should cut a clear (or blue) window in the side of the Venturi so you can see the airflow.

lol you design one then! and ill build it

[KEITH KRAUSE]

Don't be concerned with it. The pods will breath fine. I have a black/mirrored plastic piece that covers the battery and stuff too.
And on the subject of flow, be sure to remove the two floatbowl vent lines and leave the ports open to breath better. Fuel starvation, at varying levels, will result if you leave the vent lines on.
What jetting did you decide on? (Main jet, jet needle e-clip position, pilot jet, pilot fuel screw and side air screw settings?)

[Agemax]

Don't be concerned with it. The pods will breath fine. I have a black/mirrored plastic piece that covers the battery and stuff too.
And on the subject of flow, be sure to remove the two floatbowl vent lines and leave the ports open to breath better. Fuel starvation, at varying levels, will result if you leave the vent lines on.
What jetting did you decide on? (Main jet, jet needle e-clip position, pilot jet, pilot fuel screw and side air screw settings?)

i am running belmouths now, not pods. it has a dynojet stage 3 kit in. the vent tubes have been removed

[rapidray]

Yoy offer a LOT of "advice" on this site about PERFORMANCE work & have a 1085 motor with WORK done to it, with STOCK 26 VMs on it?!!! You just lost a LOT of my respect! Stick to BOLTING stuff on to your bike! WTF?!!! Is that enough criticism for you? Ray.

[Agemax]

Yoy offer a LOT of "advice" on this site about PERFORMANCE work & have a 1085 motor with WORK done to it, with STOCK 26 VMs on it?!!! You just lost a LOT of my respect! Stick to BOLTING stuff on to your bike! WTF?!!! Is that enough criticism for you? Ray.

thanks Ray. it actually runs fine with the 26's. i plan to get some bigger carbs when i can afford them but being unemployed makes it a bit tricky.

as for "bolting" stuff on, take another look and see what has been MADE, or modified to fit, by me. i dont just sit here and flick through a catalogue and buy stuff to bolt on, i use my imagination and ingenuity to personalise my bike the way i want it

[rapidray]

A set of CR 31s would be a BIG change in power!! You aren't afraid of POWER are you? LOL! Good work! Let me know when I can get clutch covers for 16 valve 1100s! Ray.

[Agemax]

A set of CR 31s would be a BIG change in power!! You aren't afraid of POWER are you? LOL! Good work! Let me know when I can get clutch covers for 16 valve 1100s! Ray.

id love more power but power costs money, how much we talking for a decent set of 31's? plus new inlet rubbers, plus new filters? lots me thinks

working on a gsx1100 clutch cover now

[KEITH KRAUSE]

Agemax, sorry about the reference to pods. I guess the pic confused me even though you did say bellmouths.
I have to doubt the plate will interupt flow but couldn't say for sure. If it's an issue then I suppose you could cut a hole out for each bell or one oblong hole for the whole set. Still would hide the batt' and stuff and eliminate any chance there is of a flow issue.
29 smoothies fit the 1000 perfectly but as you said we're talking some money and possible jetting and parts headaches. Too easy to get an abused set these days with all kinds of incorrect parts. Maybe pick up 3 or 4 tenths in the quarter? The 26's work fine and are much easier to live with. I've ran the 26's all these 32 years and I have a V&H pipe, K&N pods and 1085 kit. I KNOW the stockers partly restrict the added flow of pods/pipe but I can enjoy what I have and don't need headaches anymore.
As for the bellmouths, they MIGHT add 1 more HP at about 8K rpm but that's it. I've seen tests done long ago by a respected source that was posted here before too. GS1000 with stock intake vs pods vs bellmouths, vs wide open carbs... Only 1 HP difference from the pods and wide open.
I'm not knocking your set up but if you keep the bike long term then bellmouths aren't a good choice. Very minimal power pick up and only at optimum rpm. Filtration is very poor even if you have screens. They look cool but quality pods are a better choice especially if you have a set up that may be compromising the bell's flow.
I figured you had a stage 3 DJ kit but was just wondering what final jetting you chose.

[Agemax]

Agemax, sorry about the reference to pods. I guess the pic confused me even though you did say bellmouths.
I have to doubt the plate will interupt flow but couldn't say for sure. If it's an issue then I suppose you could cut a hole out for each bell or one oblong hole for the whole set. Still would hide the batt' and stuff and eliminate any chance there is of a flow issue.
29 smoothies fit the 1000 perfectly but as you said we're talking some money and possible jetting and parts headaches. Too easy to get an abused set these days with all kinds of incorrect parts. Maybe pick up 3 or 4 tenths in the quarter? The 26's work fine and are much easier to live with. I've ran the 26's all these 32 years and I have a V&H pipe, K&N pods and 1085 kit. I KNOW the stockers partly restrict the added flow of pods/pipe but I can enjoy what I have and don't need headaches anymore.
As for the bellmouths, they MIGHT add 1 more HP at about 8K rpm but that's it. I've seen tests done long ago by a respected source that was posted here before too. GS1000 with stock intake vs pods vs bellmouths, vs wide open carbs... Only 1 HP difference from the pods and wide open.
I'm not knocking your set up but if you keep the bike long term then bellmouths aren't a good choice. Very minimal power pick up and only at optimum rpm. Filtration is very poor even if you have screens. They look cool but quality pods are a better choice especially if you have a set up that may be compromising the bell's flow.
I figured you had a stage 3 DJ kit but was just wondering what final jetting you chose.

thanks, im running the 142 dynojet mains at the moment. the bike seems to pull a lot harder with the belmouths but i think i will revert to the pods for street use, for obvious reasons(flies,bees,children, young mothers etc,etc)

[KEITH KRAUSE]

thanks, im running the 142 dynojet mains at the moment. the bike seems to pull a lot harder with the belmouths but i think i will revert to the pods for street use, for obvious reasons(flies,bees,children, young mothers etc,etc)

OK. Most 1000 owners run the 138 mains but that's with the pods.
My bike would accept the 142's but it did feel just a tad on the rich side but the biggest issue was a moderate bog during roll on's such as typical passing. I KNEW I had the jet needles set right and I guess the momentary overlap of the two circuits while opening to 3/4 and full throttle created a bog. No way I was going to compromise the jet needle since that's the circuit you ride with most of the time. So I went to the 138's and it runs well. Maybe a 140 if available would be perefect but I'm good with it.
Most owners end up with the jet needle e-clip in position 4 from the top, just to let you know. Each bike can vary a bit but that's by far the most common setting I've found over the years in combination with a quality pipe and K&N pods.