Ducati Monster Forum

Moto Board => Tech => Topic started by: Graymonster on June 15, 2012, 01:51:53 AM

Title: Cone air filters on M900...
Post by: Graymonster on June 15, 2012, 01:51:53 AM
Hello! Possible I walked into a wasps' nest here, but nothing ventured, nothing gained ...

I'm thinking about mounting cone air filters on my Monster. My plan is to route the crank ventilation hose to end up inbetween the filters. This will (in my head atleast) create enough vacum to suck out the fumes from the crank shaft house.... I did this (successfully) on my -73 Norton Commando.

What do you think of this?

Hope you excuse my spelling, I'm Norwegian and don't trust Google translate....
Title: Re: Cone air filters on M900...
Post by: zooom on June 15, 2012, 04:01:37 AM
I am assuming this is a bike with carbs? Are there any other mods to the machine? Are you currently running an open airbox?
Title: Re: Cone air filters on M900...
Post by: ducpainter on June 15, 2012, 04:16:39 AM
Quote from: Graymonster on June 15, 2012, 01:51:53 AM
Hello! Possible I walked into a wasps' nest here, but nothing ventured, nothing gained ...

I'm thinking about mounting cone air filters on my Monster. My plan is to route the crank ventilation hose to end up inbetween the filters. This will (in my head atleast) create enough vacum to suck out the fumes from the crank shaft house.... I did this (successfully) on my -73 Norton Commando.

What do you think of this?

Hope you excuse my spelling, I'm Norwegian and don't trust Google translate....
Your English is almost perfect...

Your plan for crankcase venting...

not so much IMO. ;D

I don't think enough vacuum will be created to pull anything out.

Crankcase pressure will still push though, so there won't be a pressure issue.
Title: Re: Cone air filters on M900...
Post by: Graymonster on June 15, 2012, 05:37:24 AM
Sorry zooom, my bike is an -98 m900 with Temignoni cans, Dyno stage 2 and (for now) an modifyed airbox (more open than original...)

ducpainter: what is in your opinion not going to happen with to little vacum? Build up of fumes/pollution? I'm asking because I don't know. On my Norton I didn't experience anything wrong with the settup I'm thinking of applying to my Monster. :)
With crankcase pressure, do you mean blow-by?

Wiktor.
Title: Re: Cone air filters on M900...
Post by: motoxmann on June 15, 2012, 06:12:12 AM
the crankcase breather is only there to let crankcase pressure out, so there is never any pressure in the crankcase. as long as the crankcase breather is not blocked, it will operate fine.
the only reason the breather is connected to the airbox is so the semi-dangerous fumes coming out of the crankcase get recycled back into the engine to get burned, and not let into the atmosphere. there is no vacuum above the carbs, only airflow. if there is ever any vacuum, it means the intake is too restrictive, so you don't want vacuum anyways. having the breather connected to the airbox is just a direct path for airflow so the fumes coming out have nowhere to go but back into the engine.

so your idea is perfectly fine, it will not affect how the engine runs at all, and it will not affect how the crankcase vents at all. it just means that not all the fumes will go back into the intake. in fact, most people who alter the breather just eliminate the hoses and tank completely and put a pod filter directly on the breather port, but this tends to cause some oil buildup around that filter
Title: Re: Cone air filters on M900...
Post by: Graymonster on June 15, 2012, 06:23:02 AM
Hmmm.. I'm no expert, but I'm pretty sure there is a smaal vacum were the crank-case hose is connected to the airbox... The engine sucking air and there is a littlebit restrictiom in the filter --> littlebit vacum! :) or am I wrong... The rest motoxmann, I agree in! :)
Title: Re: Cone air filters on M900...
Post by: ducatiz on June 15, 2012, 06:46:59 AM
The factory design airbox has the crankcase vent intake at the bottom of the box, below the filter.

The pod filters are far more free-flowing than the stock airbox setup.  I think the intake hole on the factory airbox lid is about 10x30cm?  This causes the vaccum to seek other air, so creates suction from the crankcase vent line.

Remove the airbox lid and you lose a lot of that vacuum right away.

Pod filters = most airflow is going thru the filter.
Title: Re: Cone air filters on M900...
Post by: ducpainter on June 15, 2012, 05:18:00 PM
Quote from: Graymonster on June 15, 2012, 05:37:24 AM
Sorry zooom, my bike is an -98 m900 with Temignoni cans, Dyno stage 2 and (for now) an modifyed airbox (more open than original...)

ducpainter: what is in your opinion not going to happen with to little vacum? Build up of fumes/pollution? I'm asking because I don't know. On my Norton I didn't experience anything wrong with the settup I'm thinking of applying to my Monster. :)
With crankcase pressure, do you mean blow-by?

Wiktor.
I just think the area at the end of the hose will become messy.

it will do no harm.
Title: Re: Cone air filters on M900...
Post by: Graymonster on June 16, 2012, 02:20:14 AM
Thx! Appreciate your help and the way you welcome me as an new member!  [thumbsup]