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I have an 07 K1200s it has 2 snorkels feeding the airbox my 09 K1300GT has one snorkel to the air box why the change ? and I had read bmw was changing the airbox if there was a issue with the way the bike was running what was the upgrade a new air box or ? And can the new improved airbox still be bought
 

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2005 BMW K1200S
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Common sense is 2 Snorkels are better than one.
There are how to threads done for the R.
You can't custom order a car or bike and mfg select what most buyers want for that segment.
To me Dialing It In is creating the Swiss Army Knife Canyon Racer Drag Bike Sports Tourer that always has repeatable optimal performance.
Good Luck
Start with the K1200R Forum.

ps: kit out today
 

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The old airbox had trouble with warping and was replaced under warranty by bmw. NOt sure about the gt but the s and the r had the same airbox but the s had both sides cut out for twin intakes. This is why the s produced slightly more power. A few r owners simply cut out the left blank side of the airbox and put an extra intake there. The blank was quite apparent.
 

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You have to be careful with these Airbox threads, remember some years back about how the R box is the same as the S, all you have to do with the R is cut the side out that isn’t in use, you will note when stripping either bike the filter is held in by a moulding at the bottom of the Airbox and a separate plastic wedge.

Bought another filter, stripped the bike only to find my Airbox did not have the moulding at the bottom so there was no way to hold the filter apart from buying another box, didn’t bother in the end, runs well enough with K+N/full Akra system/PC set up on a dyno.
 

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two K1300S bikes, S1000R & Vespa 150 Primavera clown paint job
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The GT was tuned for less HP than the KXXS bikes. It is simple as that. The air box is more important than people think it provides a resonance for the intake air tuned to the bike performance.
 
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You have to be careful with these Airbox threads, remember some years back about how the R box is the same as the S, all you have to do with the R is cut the side out that isn’t in use, you will note when stripping either bike the filter is held in by a moulding at the bottom of the Airbox and a separate plastic wedge.

Bought another filter, stripped the bike only to find my Airbox did not have the moulding at the bottom so there was no way to hold the filter apart from buying another box, didn’t bother in the end, runs well enough with K+N/full Akra system/PC set up on a dyno.
Might want to read this before buying K&N.K&N Air Filter Review - Debunking the Myths (and why OEM is better) (nicoclub.com)

Yes, the pass air easier, but they pass an insane amount of dirt and clog upp long before a cheap paperfilter.
 

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As Beech says, the 1300GT was tuned for less power than the S & R. With the head, cam timing (268 degrees inlet duration and 256 exhaust), throttle bodies and compression ratio being identical, the power uplift was achieved solely through the different airbox, dual filter/snokels and exhaust valve (allowing the S to have a less restrictive silencer). The GT airbox was smaller, not only due to the single filter/snorkel, but to the bigger battery cutout. The intake trumpets (velocity stacks) are also longer and narrower on the GT to create a longer resonant length to help the bottom end/mid-range (though the S still has more torque everwhere due to the better breathing).

The GT also has its ABS pump right where the left air filter/snorkel would be.

I've bought a 1300S airbox and LH snorkel for my GT as I want the extra power. Don't really need it as I have the S if I want speed, but started before I got that and its an interesting engineering project. I've fitted a K1200GT exhaust cam (244 degree duration) to see how much more economy I can get. The idea (once I've finished) is to make the engine breath as well as it can with the S airbox (I'll fit the GT trumpets to keep the low-end effect) and free-breathing silencer but reduce valve overlap by 6 degrees and increase the power stroke by 6 degrees. I haven't yet fitted the airbox or exhaust or a PC V or had a dyno/calibration session but just changing the cam timing has improved economy (65mpg -UK gallons- at 75mph) and there's barely any loss of power (saw 149mph, with more to go, the other month). It's also got very very smooth, though that might be because I spent a lot of time getting all the valve clearances to within 0.5 thou of each other (they were all in spec but some at top and some at bottom so worth the fiddling). Fuelling is probably rich at some points until I recalibrate, i.e. some spots where economy is less good but I'm waiting til I've done all the mods. The main work will be in moving the ABS pump and cruise control motor down to allow room for the LH snorkel and making a smooth nose for it at the front of the fairing. I'm using a 30AH lithium battery which exactly fits the S battery cutout so no issues there.
 

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Might want to read this before buying K&N.K&N Air Filter Review - Debunking the Myths (and why OEM is better) (nicoclub.com)

Yes, the pass air easier, but they pass an insane amount of dirt and clog upp long before a cheap paperfilter.
Great article. Suspected exactly this. Its a strong argument for running paper filters and changing them often.

I've also read that the cotton of the K&N filters is quite variable in it's hole sizes - that would mean it would let in larger dust particles than it needs to for a given improvement in airflow. Sprint filters make much of this as they claim to use a more consistent, woven material (polyester): Why choose Sprint Filter?. Assume these are better but may still flow more dust, and clog quicker than paper. Unfortunately they only do a flat panel one (K1200) not a conical one for our bikes.
 

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Interesting, my 09 GT came with a K&N from the P.O, I have nothing to compare it against. At next service may try a paper filter. I've got k&n in my other big bore suzuki and no issues at all in the last 10.000km
 

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Interesting, my 09 GT came with a K&N from the P.O, I have nothing to compare it against. At next service may try a paper filter. I've got k&n in my other big bore suzuki and no issues at all in the last 10.000km
Good idea. Remember, of course, to give it time for the lambda feedback to adjust the mixture a little - in theory, if the K&N has been allowing a little more air through, it'll initially run slightly rich with the paper filter.

I think we're looking at quite a lot more mileage than 6,250 (10k km) before (on average) the extra wear to bores/rings/valve guides caused by the increase in dust particles becomes noticeable. At a guess, I'd say with these Ks, one might notice a difference between a K&N and a paper filter fitted bike at beyond 25k miles - e.g. extra oil consumption, rattliness etc.
 

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the S get 2 the GT gets 1 - the GT is designed to get a better torque spread where you need it - adding another probably does almost nothing at the top where few people take a GT and ruins the mid range torque - the thought a few numpties with no idea, believe they can do 5 mins home bodging and get a better profile and range of power deliver over hours of dyno runs and thousands of miles testing by a manufacturer is absurd

noise over substance - why not fit 3 ?
 

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the S get 2 the GT gets 1 - the GT is designed to get a better torque spread where you need it - adding another probably does almost nothing at the top where few people take a GT and ruins the mid range torque - the thought a few numpties with no idea, believe they can do 5 mins home bodging and get a better profile and range of power deliver over hours of dyno runs and thousands of miles testing by a manufacturer is absurd

noise over substance - why not fit 3 ?
KNOW IT ALLS think everyone is as dumb as they are.
Why 2 intakes? Because BMW said so! There is a point of diminishing returns.

My K1200S had stock filters but the K&N's make it quicker.
Its the Cone Design not the filter element that changes the 1300 filter.

I believe Duncan Hare knows what he is doing.
Dale Walker built my Bandit with Suzuki's OEM air cleaner in a modified airbox.
I found a happy medium with a GSXR intake cam for a 4 to 6 horsepower gain and left the Bandit exhaust cam in for a minimal mid range drop.

I bought the K1200S to get street fighter fun with Touring Capability.
The best performing most difficult to maintain bike in my 55 years of riding
 

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the S get 2 the GT gets 1 - the GT is designed to get a better torque spread where you need it - adding another probably does almost nothing at the top where few people take a GT and ruins the mid range torque - the thought a few numpties with no idea, believe they can do 5 mins home bodging and get a better profile and range of power deliver over hours of dyno runs and thousands of miles testing by a manufacturer is absurd

noise over substance - why not fit 3 ?
The GT doesn't actually have a better torque spread: if you look at the power curves, the S is just higher throughout. The ONLY differences in tune between the S and the GT are those listed in my comment above, so if you put the S induction and exhaust on a GT and adjust the fuelling to suit, you will get the power curve of the S. Of course the reduced pressure drop through the induction system matters more at the top end and gives less benefit lower down, but won't ruin mid-range torque (unless the fuelling isn't adjusted to match the extra air). A lot of people take GTs right up the rev range.
 

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KNOW IT ALLS think everyone is as dumb as they are.
Why 2 intakes? Because BMW said so! There is a point of diminishing returns.

My K1200S had stock filters but the K&N's make it quicker.
Its the Cone Design not the filter element that changes the 1300 filter.

I believe Duncan Hare knows what he is doing.
Dale Walker built my Bandit with Suzuki's OEM air cleaner in a modified airbox.
I found a happy medium with a GSXR intake cam for a 4 to 6 horsepower gain and left the Bandit exhaust cam in for a minimal mid range drop.

I bought the K1200S to get street fighter fun with Touring Capability.
The best performing most difficult to maintain bike in my 55 years of riding
:)
 

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KNOW IT ALLS think everyone is as dumb as they are.
Why 2 intakes? Because BMW said so! There is a point of diminishing returns.

My K1200S had stock filters but the K&N's make it quicker.
Its the Cone Design not the filter element that changes the 1300 filter.

I believe Duncan Hare knows what he is doing.
Dale Walker built my Bandit with Suzuki's OEM air cleaner in a modified airbox.
I found a happy medium with a GSXR intake cam for a 4 to 6 horsepower gain and left the Bandit exhaust cam in for a minimal mid range drop.

I bought the K1200S to get street fighter fun with Touring Capability.
The best performing most difficult to maintain bike in my 55 years of riding
Yes, a hairy inlet cam and shorter exhaust usually gives a good top-end and midrange. Did that on my '66 Bonneville: 750 "thruxton" inlet cam (set 6.5 degrees advanced) with standard 650 Bonnie exhaust (269 degree) and degreed them in properly and it worked a treat. Have done similar on various italian and jap bikes to good effect.
 

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aside from the different engine map it runs between the GT and the S, it has the exhaust flap valve and a very different freer flowing exhaust can (plus the air box changes)

there is always more in the mix than just numbers

the exhaust flap of the S is to partially help bring the midrange back after loosing it with air box etc.
then we have one, a touring fart bike for old duffers vs hoddies trying to loose their license, the older guy wants a refined bike with a smooth boring power profile so he doesn't need to change gear every three seconds, and one that doesn't have some air box or exhaust driven drone / resonance that will irritate hours down the road - the hoodie if still alive, just wants another 10 bhp to he can claim he rides fast when down the pub
 

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aside from the different engine map it runs between the GT and the S, it has the exhaust flap valve and a very different freer flowing exhaust can (plus the air box changes)

there is always more in the mix than just numbers

the exhaust flap of the S is to partially help bring the midrange back after loosing it with air box etc.
then we have one, a touring fart bike for old duffers vs hoddies trying to loose their license, the older guy wants a refined bike with a smooth boring power profile so he doesn't need to change gear every three seconds, and one that doesn't have some air box or exhaust driven drone / resonance that will irritate hours down the road - the hoodie if still alive, just wants another 10 bhp to he can claim he rides fast when down the pub
I've already mentioned (in the comment that you took a pop at) the S's flap valve and freer-flowing exhaust and the fact that the fuel map is different to match the extra air, so I'm not sure why you're re-stating these things we all know about.

Not sure what "there is always more in the mix than just numbers" means. This cryptic statement looks to me like a smoke screen so as to avoid having to validate (and either agree or disagree with) my correction of your assertions:
(1) that the GT has a better torque spread - I said it doesn't - only one of us is correct; and
(2) that an extra air filter/snorkel "ruins the mid range torque" - I said it won't, it will INCREASE it. Again, only one of us is correct.

The exhaust flap valve isn't to "partially help bring the midrange back after loosing [sic] it with air box etc". I'm pretty sure you have no basis for saying this (e.g. no statements made by BMW, no solid theory and no empirical evidence). As above, THERE IS NO mid-range drop on the S due to the larger airbox/extra filter (there is A GAIN). The flap valve is unlikely to provide a significant gain in torque anyway as (unlike a Yamaha EXUP-style valve located where the headers join the collector) it can't/doesn't create significant resonant effects, as it's not controlling access to any changes in section (when closed, it's just like having a more restrictive silencer). The additional back-pressure it creates when closed may help reduce over-scavenging and this could conceivably improve fuel economy at part throttle but no power gain. I'll find out when I do my fiddling (the GT will get a freer-breathing after-market can, and the S will get a full Akra Evolution titanium/carbon system). If the lack of a valve badly affects economy (I doubt it) I'll consider refitting it. The valve is there primarily as a cheat to reduce noise emissions at the speeds noise is tested for (BMW probably hint at power increase to legitimate this and fool gullible buyers).

Your final para(/essay) seems an unnecessarily obscure way of restating your (incorrect) assertion that the torque curve of the GT is wider than that of the S and you also introduce the idea of quietness/refinement: The standard GT exhaust certainly IS a lot quieter than that of the S, the bodywork (inc front mudguard) IS much more sound-damping and the bike generally feels more refined, but, based on my experience of my GT and S, the GT actually makes MORE of an airbox roar than the S at given (high) speed/throttle. In theory, having 2 snorkels/filters reduces intake air velocity and hence noise at a given RPM/throttle, so that might be what's going on (and I notice the GT snorkel has a bit of a plenum chamber in it, whereas the S ones don't - perhaps this is to damp out noise). It may just be, of course, that I'm hearing it more on the GT due to the quieter bubble behind the fairing.

If you're going to reply to this, please can you take the care to validate my points in the way I've validated yours - I'm responding directly to the points you make, validating them, agreeing where I can, disagreeing where I have reasons to and providing you with those reasons. I hold my conclusions lightly and will change them (and gracefully acknowledge the correction) if someone presents good reasons. That's the normal way in which people discuss the world to try to understand it together. I sense (from this and your other contributions on here) that your approach is not to validate others but to introduce random conclusions with no clear premises or connecting reasoning, old information presented as new, cryptic ("smokescreen") statements, mini-essays/quasi-political statements, aggressive-sounding wording etc (i.e. "noise over substance", to use your phrase). It's rather tedious, taking the time to reply logically and reasonably to what someone says, only to recieve a random diatribe back. If you have any clue what you're talking about then you have a chance to prove it.
 

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Not sure what "there is always more in the mix than just numbers" means. This cryptic statement looks to me like a smoke screen
(1) that the GT has a better torque spread - I said it doesn't - only one of us is correct; and
(2) that an extra air filter/snorkel "ruins the mid range torque" - I said it won't, it will INCREASE it. Again, only one of us is correct.
"always more in the mix than just numbers" = the way it rides / feels and the NVH. Your can't feel if it's got a peak of 4 bhp and 7lb ft of more torque, but you can feel how smooth / progressive and glitch free a curve is - and that matters a shed load more - particularly when 97% of the time it will be around 4k rpm on part throttle

the other bit, I'd wanted to add a brief summary of what's different - I didn't read your list as more info than we need - and after quite a few words I hadn't spotted you mention the different Map

the flap valve is exactly to help with mid range torque and emissions of HC and noise - Yamaha were there many years earlier - cheap mans VVT
 

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aside from the different engine map it runs

there is always more in the mix than just numbers

the exhaust flap of the S is to partially help bring the midrange back after loosing it with air box etc.
then we have one, a touring fart bike for old duffers vs hoddies trying to loose their license, the older guy wants a refined bike with a smooth boring power profile so he doesn't need to change gear every three seconds, and one that doesn't have some air box or exhaust driven drone / resonance that will irritate hours down the road - the hoodie if still alive, just wants another 10 bhp to he can claim he rides fast when down the pub
... "between the GT and the S, it has and a very different freer flowing exhaust can (plus the air box changes)"
What is the exhaust flap valve ? Also the factory muffler (UK's OEM Can) is something I've never seen in real life and irrelevant as every rider removes it 1st.
While I like your comparison / opinion I disagree.
I'm a 74 year old "hoodie" that's always squeezing out more HP and Torque. I fanaticaly adjust every to be a "hair trigger" to save precious milliseconds. Speed is the drug and I need a hit.
While I split lanes continously and always pass not hide from the police I haven't got a ticket in 40 years. To me the S is an old mans bike and I appreciate the modular saddle bags, full fairing and full seat.. I've been trying to add a topcase so I can take a long trip.
This forum has two groups:
1) Riders that share there knowledge and experience.
2) BMW purists that that think only BMW knows what they are doing.

I pity those that find rapid up or down shifting work.
 
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