Dendrz ref: airbox mods

The mods that have been done to my airbox are in the same place as the Chambon SM bike,

But I have not cut hole's in the side panel, only the airbox, however if its good enough for Chambon its good enough for me!!!

I'll give it some thought first as I am pleased with how my DRZ400S is running at the moment(but if more power can be had, well you know how it is)

I also was advised to run the bike with the airfilter dry(no oil) which would help airflow, but I opted for a compromise by lightly smearing the filter with some 10/40 oil, what do you reckon?



The thought of running the air filter dry sounds scary to me. You would get better airflow, but at what cost? Needing to rebuild the engine in a few months? I don't know what type of conditions you ride in (dust, dirt), but without that oil on the filter there would be a ton of dirt going through my engine. I've used 10/40 motor oil and it seemed to work fine. But in the interest of caution, I'm using Maxima air filter oil now. But whatever you do, use something.

I read your post about the advantage of the side holes in the airbox but after thinking it over i cut the top, i do quite a bit of offroad aswell.

Problem with cutting the holes in the sides for me would be for the offroad forays especially where water crossings came into play, i am the one voted most likely to need waterwings lol.

The holes in the airbox sides and sidepanels would be neat on a motard.

As regards lightly oiling the filter, i always oil them i run some fireroads here summertime and they are dusty.

Have you considered making some sort of a Ram Air?

nothing that would create alot of wind resistance, but something that would bring fresh air into the airbox, maybe even something that could be sealed shut.

just an idea

You can always duct tape the holes up when you go off road. That's what we used to do when we rode MX bikes offroad, and we new it would be wet and muddy. A YZ125 with the airbox taped up is a tank! :)

The condtions I ride in tend to be pretty dust free(pretty damp, but not muddy) it on a old open cast mine where I ride most which is like a shale type ground, plus road condition's,

The mechanic/tunner that told us about running the filter dry reckoned the suzuki filter being a dual filter item had load's of protection and would still offer good protection as such, my father used to run his YZ465 and DT175 with dry filter's to and never experienced any problem's,

However I am not saying this is the way ahead, You guys in the USA,Canada ride in very different conditions to myself(far more extreme I would say, not to many deserts in Scotland!!!) and probarly do a lot more off road riding than myself(and probarly much better too!!!) and agree with what you say with oiling the filter(better safe than sorry)

If I was using my DRZ as a Super Moto I would be out with my tool box hacking more hole's in the airbox/side panel's too see what could be done,

I saw a picture of a supermoto XR650 which also had it's side panel's chopped for more airflow, infact it was on , its got dyno chart's and such(I'm sure thats the web site adderess) maybe worth checking out Gyro?

Ram-air, why not, if it work's on road bikes at high speed it might also work on a supermoto, mind you I think Ram-air only really has an effect at really high speed's(I'm no expert on this so only a guess),



Oil that filter and wring it out. You need the oil to trap the dust etc. The foam just provides the surface area so it dosen't restrict to fast. Clean it and oil it often. It is a nasty job but will extend the life of your engine.

Regarding Ram air. It is not effective untill much higher speeds than we are capable of. $.02 :)

I noticed the snorkel on top is not in a freeflow air area. There are a lot of wires and stuff leaving

the airflow intake ambiguous to and into the box. The bike moves a ton of air and it is smart to unclutter this area. Cool air intake creates horsepower (inner cooler). I am resistant to modify any airbox per say. Viewpoint of past roadracer.

CB :)

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