Intake hoses - do we need them? Lose or keep?

[AndyH]

The left rubber intake hose fell off the air box recently: it left a melted smear on the cylinder fins.

As it happens, the bike's been running much better recently, better fuel consumption and much better behaviour around town in heavy traffic. The hose, well, the one that's left anyway, are angled down and seem to suck hot air off the cylinders which won't help when at a standstill, I'm sure.

 

I've looked at various posts on the forum and can't find opinions as to what they do to benefit induction.

 

For example, without them, is there a ram air effect? Is this a good thing?

The cross sectional area of the aperture seems smaller than the bit they go onto: good or bad?

Do they cause poor running in traffic as I suspect?

They must have been put on for a reason - to stop crap (insects, discarded cigarette butts, small birds etc.) flying into the air box, perhaps?

 

So, do I lose the other one or replace the lost one?

 

Votes please.

[docc]

My vote: ditch 'em!

 

I suspect they are only to muffle the drive-by intake noise for emissions testing. No question they restrict the intake (bad) and at idle suck the intake air that's rising off the header pipe (extra bad).

 

Probably no significant ram air effect under 135 mph.

[jwh20]

Probably no significant ram air effect under 135 mph.

 

And you know this how?  Your V11 must be setup much hotter than mine as I don't think it will go anywhere near that fast!!  

[docc]

Okay, the key word there was: 

[PDoz]

 

Probably no significant ram air effect under 135 mph.

 

 

And you know this how?  Your V11 must be setup much hotter than mine as I don't think it will go anywhere near that fast!!  

 

Why not? My motor is stock except pipes ( I think) , it easilly punches past that .

[luhbo]

The Optimiser tells me that I can use more fuel with the snorkels attached then without them. That's the techincal aspect why I like them. What I really don't like is the noise the intake makes without them.

 

BTW, I'm glad you did not use the phrase 'no-brainer' others often use in this regard, docc

 

Hubert

[AndyH]

Ditched 'em. Runs Ok and performance acceptable as far as I can tell so far.

 

However, only time will tell.

[Skeeve]

The left rubber intake hose fell off the air box recently...

I've looked at various posts on the forum and can't find opinions as to what they do to benefit induction.

 

That's because they don't do anything to benefit induction: they're there exclusively to minimize intake noise.

 

 

For example, without them, is there a ram air effect? Is this a good thing?

 

 

There is no ram air f/x from these things. The only Guzzis w/ ram air intakes were the Daytonas & Spot/Sporti. The ram air was tested at one point & found to only increase output by something like 1/2 horsepower [i forget the exact conditions; it's in Greg Field's [u]Guzzi Big Twins[/u] book, as I recall.]

 

 

 

The cross sectional area of the aperture seems smaller than the bit they go onto: good or bad?

Do they cause poor running in traffic as I suspect?

They must have been put on for a reason - to stop crap (insects, discarded cigarette butts, small birds etc.) flying into the air box, perhaps?

 

Bad. Not really, altho' they certainly don't help. The were put on to keep induction noise trapped inside the airbox so the bike could pass arbitrary governmental noise standards be legally imported & sold here.

 

 

 

So, do I lose the other one or replace the lost one?

Votes please.

 

Lose it & then look up "airbox mods" here in V11LM to see what you need to do next to unleash the mighty V11 that is currently half-strangled...

[luhbo]

Lose it & then look up "airbox mods" here in V11LM to see what you need to do next to unleash the mighty V11 that is currently half-strangled...

Dream on

[Camn]

http://www.bikeboy.org/v11sport.html

"
We ran the bike all std, then removed the little air snorkel thingys from the air box entry tubes. Which made a little more noise and gave maybe a tad more mid range to top end power.
"
 

[Gio]

I cut mine back and drilled the airbox at the same time. It may, or may not, run better ... but sure sounds like it does! 

[LucaKungs]

The left rubber intake hose fell off the air box recently: it left a melted smear on the cylinder fins.

As it happens, the bike's been running much better recently, better fuel consumption and much better behaviour around town in heavy traffic. The hose, well, the one that's left anyway, are angled down and seem to suck hot air off the cylinders which won't help when at a standstill, I'm sure.

 

I've looked at various posts on the forum and can't find opinions as to what they do to benefit induction.

 

For example, without them, is there a ram air effect? Is this a good thing?

The cross sectional area of the aperture seems smaller than the bit they go onto: good or bad?

Do they cause poor running in traffic as I suspect?

They must have been put on for a reason - to stop crap (insects, discarded cigarette butts manufactured by electronic cigarettes manufacturers , small birds etc.) flying into the air box, perhaps?

 

So, do I lose the other one or replace the lost one?

 

Votes please.

I am very much confused.. I have been dealing with similar problem so I am curiously following what people vote..

[sp838]

"Why not? My motor is stock except pipes ( I think) , it easilly punches past that [135 mph] ."

 

Unless you've made extensive modifications to both the engine and the transmission, I find it highly doubtful that your V11 "easily punches" past 135mph. The top speed as listed in the workshop manual is 137.5mph. The only way you could go faster is if you've increased the maximum safe RPM of the engine (and modified your ECU to allow you go past the rev limiter) and/or modified the gear ratios in the gearbox. Or if you are running a significantly larger diameter rear tire, which would be stupid. All sounds very unlikely to me. Unless you strapped your V11 to the back of a Lamborghini...

 

(Sorry for going off topic.)