GS intake runners fitted to my 1100S: WOW !!! Pics added.

[gus]

Length. Maybe slightly different shape? Never compared the two.
Gus

[HerrFlick]

What's the differenec between the inlet ducts FUT41405 and FUT 41210

(bottom of the page)

http://www.motorworks.co.uk/vlive/Shop/ ... 0_30_FA_20

and which one do I need for this mod?

The long one is FUT41405. (GS intake tube) L and R are different so you'll need both. (Short funny-looking one is the 'S' tube).

Surely that BM fiche diagram makes it perfectly clear...





Then follow my "how to" pics.

https://www.dropbox.com/sh/epl92avneo96 ... stallation


Note the two self-tapping screws that lock the 's' tube to the airbox: you'll need a 1/2" longer pair to lock the GS tube where it's been pushed down inside the 's' tube.







!!! Drill !!! holes into the GS tube (when it's in place), as the self-tappers won't bite into the plastic, and just squash the GS tube inwards.







Cut the GS tubes at this position and angle, in the direction of the curve of the GS tubes.







.

[NA1959]

Whenever i see this modification suggested it always makes me laugh, it's not new, it's been going for years.

GS riders fit the RS airbox tubes and rave about the performance improvement.

RS riders fit the GS airbox tubes and rave about the performance improvement.

Now 1100S riders have joined in the merry-go-round.

Everyone will fit GS tubes to their 1100S.
A year down the line i'll fit a pair of standard 1100S tubes back onto a customers 1100s and tell him they're special tubes and he'll rave about the performance improvements

I agree we can all make mods but at times we can "balls" up a good bike.

All interisting stuff how does MPG be altered after all this work as I find the tank crap at standard settings.

Keep up dating this interisting post

Hi NA1959,

If I limit the revs to abt 4200 (70mph) I get an extra 40mi per tank. And always looking for 7th gear.

The problem is staying below 4000 as it's now a case of yeee-haaaaa but I still get better consumption than pre-modification.

As Mike B. has said, this is a very easy (and reversible) change to make. Just go and do it. You won't be sorry.

Mine are never coming out. It's not only the performance lift, but the smoother rideability from 0-8000rpm

I now have a pair of RocketSprockets which I'll be fitting after then next dyno session.

Then I'll be looking into making a single runner (per side) in carbon fibre for the factory finish look.


Cheers

John C.


.

You should tell BMW about your results. It would have saved them millions of pounds developing the 1200 engine, and they'd have a faster bike with better fuel consumption. .

Neil still a GS man to the full

[Dai wiskers]

Morning all i have been giving this a lot of thought going back into my dim and distant past longer velocity stacks were used to allow the motor to get cooler air in to the engine as it condenses better than hot air this is why your bike runs better on a damp misty day

Now we all know our bikes are set up to run week to pass certain emission regs most of the go faster mods that are done acctually weeken the mixture further [ free flowing exhaust, inlet duct, val singleton, etc,] they will all inprove performance by allowing the motor to breath better but unless we get more fuel in there we are fighting a losing battle as we are going to burn valve's, melt pistons, etc, so how do we get more fuel in we can remap or fit a power comander both expensive and need setting up on a rolling road to get the best out of them or we can fit a accelerater module cheap and works well on most bikes, or we can restrict the intake most of our bikes still have the plenium chamber fitted from what i can see fitting the gs intake tubes is infact restricting the intake from the plenium chamber so the motor gets less air this is why i think it works in getting the motor to run better but i don't think this is the best way to richen the mixture up

One of the mods that i have been playing with is a prefilter[washing up scouring pad] fitted at the front of the intake duct this along with the wideband lambda sensor seems to give good results in the warmer weather in this cold weather we have been having i have had to remove the prefilter and also disconect the accelerator module with these both in place the motor was showing signs of over fueling[ratteling at motorway speeds sounded to me like the bores were getting washed] the wideband lambda sensor is still inplace and seems to work smoother than the factory specified narrow band one

Thanks for listening Dai

[gus]

Hi all
Why don't you just fit a dirty air filter? that will do the same job.....
Fit a fuelling device to sort out the flat spot and improve throttle response. Job done. Properly...
Gus

[Mike B]

It's not fueling

it's the tuned length & bore

http://auto.howstuffworks.com/question517.htm

it works very much like an expansion chamber on a two stroke engine.

tuned for a given rev range. The GS tubes are tuned for a lower rev band than the S tubes. hence a nice increase in mid range power.

I must ride a GS sometime, bet they are quite nice.

[gus]

My reply was to dais theory of restricting airflow to richer up mixture. I know a little about inlet tract lengths etc etc affecting how a engine performs. I would like to see some figures of before and after to see what exactly is happening .
Gus

[el-nicko]

Well I'll give it a try. I've just bin down to B&Q an bort 2 metres of 50mm dia black plastic pipe for £6.20 so i recon i'm gud to go.

[Blackal]

Well I'll give it a try. I've just bin down to B&Q an bort 2 metres of 50mm dia black plastic pipe for £6.20 so i recon i'm gud to go.

You look a bit like...............



Al

[ianbcr]

i thought you had just mugged rolf harris for his didgeridoo nick.

[el-nicko]

I'm falling about boys.

[HerrFlick]

Looking for a bit of low speed torque there El Nicko?

... at about minus 127rpm




.

[el-nicko]

Ha ha, I see where you're coming from Herrflick. Yes a little too abitious so I've downsized 'em a shade, cut 'em to length, chucked in a lathe and bellmouthed 'em useing a heatgun. Will fit tomorrow.

[HerrFlick]

Looking very good there El Nicko.

Don't be worried about adding a bit more bell either - it will help more.

You'll find you'll need a gentle curve along the length of the choobs, as per the GS items, to fit in the airbox, but I can see that won't cause you any problems.


Busting to hear how they work out.


Cheers

John C.

[HerrFlick]

Ha ha, I see where you're coming from Herrflick. Yes a little too abitious so I've downsized 'em a shade, cut 'em to length, chucked in a lathe and bellmouthed 'em useing a heatgun. Will fit tomorrow.

Where did you get/make the El Niko emblem on the fairing?

Looks very good (as well).


.