anyone running pods on their 1st/2nd gen?

i bought some filter pods for the carbs. well its so tight in there i'll need to adapt them to fit. im thinking i'll need some 90degree bend tubing for 2 and 4 and a straight adapter for 1 and 3. or will it just run like poop if i do this? its all apart so i cannot run it to test it out right now


any help/ideas?

 

I cannot imagine it will run well without a lot of experimenting with jets and some dyno action.

 

It'll run like poop.

 

Actually, this is a great setup on the early V4's. You'll need to fabricate a spigot of sorts that mounts to the top of the carb body which will allow you to clamp the filters to them. There is some power to be gained by this, so if you are willing to do the work it will be worth it. There will be some jetting work needed (probably will want a Factory Pro jet kit) but you should be able to do this without a dyno.

What kind of exhaust are you running?

 

Hi Vernk; My experience with hood scoops , ram air and cold air induction on race cars tells me that it may be nearly impossible to make this system work effectively. My reasons are as follows,each of these carbs are located in a different area of the bike. When the bike is running at speed there are different amounts of pressures and turbulence at each
carburetor intake point,meaning each carb will be experiencing different amounts of
air volume. Some of the carbs may even be experiencing a vacuum condition or air starvation. So the fuel jetting would have to be all over the place to get an equally
proper or optimum mixture so as to make good effective power.
Now lets say after many track tests we were able to make this unequal system work,
Once we increased or decreased road speed we would need to make additional jetting changes because the pressure and turbulance that the air intakes are seeing are not linelar, so we would have to continue to reevaluate for different circumstances. Like chasing ghosts!
So what I believe we really want is the stock or close to stock air box back on the motorcycle. Possible we could try and open up the intake path slightly,but I believe
the bike will produce much more consistent power with an air box with a commom air
intake point. Jamie ,sorry to rain on your parade, I know you have considerabily
more knowledge concerning racing and tuning these machines, but I have spent
countless hours working on and sharing data regarding situations like this. Thanks for
hearing me out . eddie

 

I heard you out Eddie, but this was a standard setup on race bikes from that era. It is not anything that hasn't been done successfully before. Race bikes used to run with just screened velocity stacks and no air filter at all. You could actually tune the intake tract by lengthening or shortening the adapters. The new Yamaha's actually have movable velocity stacks that lengthens or shortens the tract length via servo's and sensors for optimum power. It will only run like shit if you don't jet it correctly. As for the turbulence argument, I am inclined to respectfully disagree with that too, but that's just my opinion from tuning with K&N filter pods on quite a few different types of bikes, with great success.

 

Way back when, Rad-Induction Air Systems had a kit to use individual filters. I was able to copy the instructions ( not much info on jet sizes) and measure one of the tubes. There wasn't a flange to measure so I'll have to come up with that on my own. I'll try to dig up the pics I took.

 

Whoa! I agree with everything you stated when it comes to cars, but it's a big stretch to apply that to motorcycles. The carbs are under the tank and pretty well shrouded, so the air available to each carb is going to be the same. We aren't taking about a ram-air system or cold air induction - just four cone filters attached to each carb with the airbox eliminated.

This system works and makes good power. The only problem is making the parts needed to mount the filters. I started on a design for this a long time ago but stopped (I can't remember why) and never went back to revisit it. Sure, there will be jetting issues but no more so than tuning for a header or other engine mods.

Vernk - I say go for it man. If you do, be sure to let us know the results!

 

OK use guys; I am not sure why most of you feel that there isn't a direct relationship
between cars and bikes,especially on intake systems. We are still dealing with all the same principles of induction. I am not aware that these principles change between cars and bikes ,or bikes and aircraft or bikes and marine applications. However if alot of you
have worked on individual intake systems like you have explained and have had good success then I feel that I must believe YOU. My knowledge of intake systems is also based on actual practical experience. What I have learned from that is both carbs and injection
systems like a smooth non turbulant delivery of air, where each cylinder can get just what it needs.
Which is the same amount, give +/- a few percent as its companion cylinders.
I believe that alot of you have experienced improved performance with these individual
systems where each carb. is getting various amounts of random air because the origional
air box/ filter was so very restrictive or undersize that anything was better than the orig.system. Thanks for listening. eddie

 

Just a little side note and further food for thought, sort of off topic but since we are talking about this stuff...taken without permission from RC51.org.

BTW because someone always brings up the fact that they use K&N filters in their car or truck & they do work under those conditions I must add that I too use K&N filters in my vehicles & they do show definite increases in power & throttle response, but cars are differerent from current bikes in that they have a closed loop Fi system that can compensate for the air flow variance whereas bikes use an open loop Fi system that cannot automatically compensate. Adding supporting evidence to my theories of airbox turbulence you will be interested to know that K&N has developed many different types of turbulence diffuser inserts for many different makes of cars & trucks that lessen intake turbulence when using their filters to increase performance. So far nobody has developed a way to even test for turbulence on motorcycle induction systems let alone cure it...

 

Thanks NB; My discussion was not about any particular brand of cycle or car air filter.
Nor did I say that I ever increased or decreased engine performance with the use of a K&N filter. My statements were made in the hopes of sharing some of my general test info/data. Many times,I have found that modifications that look straight forward and common sense like really dont perform as we think. Something I know is that air turbulance causes fits when trying to tune/optimize any intake system,I didnt say that I had a cure all for fixing it. Another thing that I do know is a smooth flowing,consistent source of air will always help improve the performance of any intake system,whether it be in the land, sea or air. eddie

 

That is all too true Eddie!

 

All of these points aside, the bottom line is that on the early V4's running individual filters and eliminating the airbox makes more power. You can debate as much as you wish as to why this is the case, but it doesn't change the facts. Many folks have done this and it's proven itself. This was back in the 80's when we had a different magnetic field around the Earth....

 

OK; Enough of my theories, if one makes the modification and it works,then I suppose
that is as far as we will take it. To all who own the early model carburetor type
VFRs,go for it. In doing so, try to keep in mind how todays hi perf bikes get their
air. We have had a little fun with this topic,however as we modify older
machinery lets not forget what we have learned . eddie

 

so how about them eagles?

 

wow, i had no clue this was such a big discussion. i leave you kids alone for a couple days and this is what happens? anywho, i am going through with the modification. i've made plates for the carbs. i still have to trim and shape. i will tack on tubing and either miter cut and weld a bend. or use rubber hose to end attach the filter pods. i will see and report back when she is finished. it will be some time as the bike is pretty much apart at this time. aside from this is the f4i rear wheel and subframe adjustment. i will update as i can with the pods and post up pics.

 

I did this same thing on my '83 vf750f. I plan to create a permanent solution for attaching the filters but I have found that the set up I am running now seems to work fine though I will eventually change it up. I cut up the metal carb holder/air box bottom so that it would still hold the carbs together but have room for the filters. I then put in the plastic intake boots and attatched the filters directly to the boots. I used some hi temp sealant to fill any holes and put it all back together. I need to re-jet badly but I have been running the bike as is for over a year now though I have lost some high end power. A re-jet should fix this. I emailed dave dodge and he told me he ran a similar set up on his old race bike with velocity stacks I believe and he told me the Jet sizes he used but I have since forgotten and lost the email so I plan to email him again. There is a pic in my gallery that gives a rough view of what it looks like with the air box removed and red pod filters attached.

 

some progress

 

Very nice keep up the good work.

 

Nice work, but those sharp 90 degree bends may give you tuning fits at speed. The air is going to be causing a ton of turbulance when it hits the corners. Sweep 90s would be better. Or at least go 45s and shorten them up a bit so the filters are vertical.