Sewer Pipe Ram Air

[Guest tmartin]

The stock V11S rubber intake snorkels, located at the front of the air box, appear to be somewhat restrictive in as much as they have small, narrow openings. I wanted to find a way to increase the size of the air intake for the air box without resorting to drilling holes in the top of the box or buying an expensive air box fix-it kit. Here is my solution.

 

Next time your in Home Depot (or other plumbing supply store) purchase two PVC 1-1/2 inch diameter “long” 90 degree elbows with female ends. Remove the stock rubber snorkels by loosening the hose clamp that secures them to the air box. You will find that the inside 1-1/2 inch inside diameter of the PVC fittings are a perfect fit when placed over the air box inlet openings. Cut the PVC elbows as shown in the photos and file/sand the openings smooth. Position the fittings on the air box inlet holes as per the photos. You may want to do this with the air box installed on the bike to get the angle just right. There is plenty of room under the tank for the new snorkels to fit. Once the PVC pipe is where you want it drill holes (sized for the sheet metal screws that will be used to fasten everything together) through the PVC fitting and the air box. Use three (per snorkel) number 6 sheet metal screws to fasten the sewer pipe to the air box. That’s it--your finished. I choose not to paint the sewer pipe and left it an “industrial” white--most of my motorcycle buddies already say that the Guzzi engine looks like if belongs on a tractor and with the sewer pipe installed it now looks like something from under the kitchen sink. See photo below.

 

This project should take about two hours to complete depending how much one fiddles with the shaping of the elbow inlets. For the budget minded the total cost is around $5.00 including the screws. As far as a performance increase I don’t know how much difference sewer ram air makes as I installed a PCIII and home-made performance exhaust at the same time that I did this modification. The intake noise is slightly louder at WOT. After some MAP tweaking with the PCIII my bike gets 42 mpg and has no flat spots during acceleration. Like a vasectomy the sewer pipe ram air modification is completely reversible should you get tired of assorted wise cracks from the inventively challenged.

[Guest Brent]

It's funny that you should post this now, because I was thinking of doing something similar, but with hoses made for automotive use. (I assume that a hose exists that has the same diameter as the snorkel...) I wonder, did you consider this also, and if so, what made you go with PVC?

 

If I do this, I'm thinking about routing the hoses forward, to just behind the steering damper where the air is probably coolest. But I haven't decided yet whether to do this or to do something with the air box--or do nothing at all...

[Guest Tracy]

I used PVC because the inside diameter was a perfect fit on the air box. Also the bend in the PVC was a good fit with the tank/frame, etc.. I feel that the stock air box volume may be tuned for mid-range power as many are on other brands. Removing the air box or drilling holes would cancel this effect. I have no hard data on a Guzzi to back this up but the theory is solid. The PVC is long enough to have the opening below the tank (unlike then stock snorkels) and I cut the angle, on the end of the pipe, to “scoop” air from in front of the cylinder heads. I posted a picture but I hasn’t showed up yet.

[Guest tmartin]

Here is a photo of the pipe

[Guest tmartin]

Here is the top view

[jrt]

Pretty cool idea, Tracy. I like the industrial look of it.

Have ya'll (best Texas drawl) thought about using radiator hose? It can take the heat better than PVC (PVC has a nasty habit of releasing HCl gas when it gets too hot) and the color is black. I was thinking about the big pre-bent sections that go to/from the radiator.

 

Cheers,

Jason

[al_roethlisberger]

Nice modifications

 

When I first got my LeMans I too had given some thought to modifying the snorkels, and even building a "ram-air" from the snorkels through the fairing behind those black winglets we've got in front of our heads. But feedback from several lists and "tuners" turned me on to the limited, if any, benefits this would provide.

 

Some additional info on modifying the snorkels and any "ram-air" benefits from my thread.....

 

LeMans Ram-Air Thread

 

 

...it seems that ram-air, or even rerouting the snorkels has been extensively discussed since the introduction of the Sport1100 bikes in the 90s(which had the same air-box, but with "real" ram-air through the fairing), and the educated consensus from several "tuners" and aeronautical engineers is that there is no benefit unless you could drive the bike to well over 100Mph.... and even then it would be minimal.

 

The unanimous feedback was that "ram-air" on bikes like many out there was merely marketing.

 

However, it was noted that inducting cooler air from somewhere other than above the cylinders would be desireable, and might improve economy a bit.

 

It's too bad really, as I was pretty excited about giving a try

 

al

[dlaing]

Don't let them stifle your fun, Al!

I too have been procrastinating on building a ram air setup.

I believe that the ram air can be increased at regular highway speeds by increasing the size of the intakes.

An interesting factor about ram airpressure is that there is a stagnation point where the pressure can not be increased unless the wind speed is increased. So, my theory is to increase the air speed by using a megaphone type intake.

Another idea is to keep the stock airbox and forward mount K&N pods. It would be a 2into one into 2 intake system!!!

Thanks for the great tip on the pipe fitting, Tracy!

Yo Brent, do you know if ABS will act differently at high temps compared to PVC?

[Guest J.R.]

How about a little fan at the end of the snorkle to add the needed pressure?

Some what like a mini super charger that decresses the fan speed when the necessary pressure is acheived.

<_<

[Guest Guest]

You'd need a massive high-speed/efficiency fan to make any difference above ambient air-pressure.... an impeller in fact.... no little fan would do. And in fact, if not adequate, the fan would actually impede air-flow.

 

Supercharging is no small feat and a whole other topic , hence the high cost and energy required.

 

al

[al_roethlisberger]

...awww shucks! I thought I was logged-in...

 

Hey Jaap, can you add 2 to my message count?

 

al

[Guest davidb]

kawasaki had stated in a recent article that thier ram air provides 5 to 7 hp on the top end. and the curve starts at 40 to 50 miles per hour. Hold your hand out while going 50 and you see if you had a air horn your intake will be at a positive In WC. where as running a lidless top would probably be at zero and a stock box with the air inlets small and pointing down will have a negative inches of water.

[Guest geno929]

So I too have been thinking about making a "ram air" for my 2000 V11 Sport for a long time. Yesterday we got through rebuilding a 98 Triumph Daytona. Used two bikes to make 1 well running bike. Anyway, we had left over parts, including the ram air tubes that came on the Triumph. The end on the tube fit over the snorkle intake perfectly. Used the same clamps and all. Routed them just under the tank and they ended right behind the steering dampner. I used zip ties to pull them inward a bit. They look excellent. Very subtle. Have yet to take them for a good long ride, but I'll keep ya posted on their effect.

[RonV11]

Pics?

[helicopterjim R.I.P.]

If you want real ram air put a blower on your bike!