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Discussion Starter #1 (Edited)
Question re Turn in (Torque Arm) from Noobie (Oz)

Hello to you all
I have just purchased a K1200GT 2004 and it turns it pretty slow.
On a previous bike I had, R1100S, I changed the Torque Arm for a slightly shorter version and it turned in a lot easier, raising the tail in the process.
Can you do the same to the GT and is there a BMW model that runs a shorter version that is interchangeable?
I would be interested in an after-market one as well as they look a lot better than the pressed steel BM version.
What length (centre to centre) would a shorter version be? Roughly measured the one on my bike is about 270mm c/c or about 310mm overall.
Sorry about the metric but I am in Australia!
Thanks :clap:
 

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NO.
Not one I have ever seen.
this bike a an enclosed drive shaft. There is an aluminum tube that prevents you from using a shorter arm.

try inflating yout front tire to 40 PSI for quicker turn in. You may also need slide off the seat to move weight to that side of the bike. read about it in A Twist of the Wrist #II by Keith Code.
 

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Discussion Starter #3
Torque Arm shortened to improve turn in

Thanks for your input.
I believe that the GT/RS rear end shaft drive is similar, if not exactly the same as the R1100.
Also, I am not keen to ride with 40PSI on the front. These front ends already feel a little wooden with the suspension setup. I know that the tyre profile is important as well.
I have read that people have talked about changing the torque arm so will keep investigating
Ta
 

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The Fllash, He said torque arm, not the swingarm. You can change the torque arm.

You can use a LONGER torque arm if you want a shorter wheelbase, BUT, as voxmagna said, you will be putting more stress on the driveshaft.

Here is a link to such an arm:
http://pirateslair.net/TorquePL.htm

The correct way to raise th rear would be custom suspension plates, which will raise the rear without affecting the suspension geometry. That or get longer custom rear shocks ($$$$)

http://jocke.selincite.com/bikes/sandbar-dogbones

Most of these parts are marketed to K1200S/R bikes, but your bike has the same suspension, so they should work just as well.

Of course, different tires (and thus different tire profiles) will change your turn-in feel as well.
 

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Tyre pressure is critical! 40psi is considered optimum for these bikes as they are hard on front tyres. I fitted Ohlins which gives the ability to lengthen the rear shock, and thus raise the rear end. I increased the shock length by 5mm which steepened the steering rake and in turn produced quicker steering. It will never be a 'sports' bike, but its better than stock when set up with good rubber and correct tyre pressure. A drop of only a couple of PSI in the front tyre will create poor handling and the 'turn in' feel in your ride. :yeow: Funny thing that 'wooden' feel.... A bike mag jurno wrote that many years ago and it seems to have stuck. Can't for the life of me understand the logic in it. :dunno: The bike handles impeccably over a whole range of road surfaces, and the rougher it gets, the more the big 'K' strives on the conditions.It simply takes a little getting used to :clap: . Many times I have left others behind as they struggle to cope with less than perfect conditions. Yes they are on the heavy side, but they dissolve huge miles with little effort, and absorb pot holes and road carnage with ease. Thats my take anyway.... :teeth
 

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Discussion Starter #7
K12GT 2004 Classic not new version

aznatama said:
The Fllash, He said torque arm, not the swingarm. You can change the torque arm.

You can use a LONGER torque arm if you want a shorter wheelbase, BUT, as voxmagna said, you will be putting more stress on the driveshaft.

Here is a link to such an arm:
http://pirateslair.net/TorquePL.htm

The correct way to raise th rear would be custom suspension plates, which will raise the rear without affecting the suspension geometry. That or get longer custom rear shocks ($$$$)

http://jocke.selincite.com/bikes/sandbar-dogbones

Most of these parts are marketed to K1200S/R bikes, but your bike has the same suspension, so they should work just as well.

Of course, different tires (and thus different tire profiles) will change your turn-in feel as well.
The Torque arm on my bike is underneath not on top so shorter torque arm = raised rear end.
BMW uses the same shorter torque arm on the R1100S Boxer Cup in conjunction with the slightly taller suspension setup.
No issue with the drive listed with this mod and the Boxer Cup was the performance version expected to be riden harder. The angle of the drive shaft has some tolerance to this mod with no expected additional wear on the shaft. Of course it is designed to move up and down with a change in the drive angle.

I checked with my mechanic today (BM specialist) and he did not believe a slightly shorter arm would cause any issue.

Now just to decide which length to use and what model it can come from. On the R1100s you can use a stock GS arm as it is shorter
 

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Discussion Starter #8
flyingkiwi said:
Tyre pressure is critical! 40psi is considered optimum for these bikes as they are hard on front tyres. I fitted Ohlins which gives the ability to lengthen the rear shock, and thus raise the rear end. I increased the shock length by 5mm which steepened the steering rake and in turn produced quicker steering. It will never be a 'sports' bike, but its better than stock when set up with good rubber and correct tyre pressure. A drop of only a couple of PSI in the front tyre will create poor handling and the 'turn in' feel in your ride. :yeow: Funny thing that 'wooden' feel.... A bike mag jurno wrote that many years ago and it seems to have stuck. Can't for the life of me understand the logic in it. :dunno: The bike handles impeccably over a whole range of road surfaces, and the rougher it gets, the more the big 'K' strives on the conditions.It simply takes a little getting used to :clap: . Many times I have left others behind as they struggle to cope with less than perfect conditions. Yes they are on the heavy side, but they dissolve huge miles with little effort, and absorb pot holes and road carnage with ease. Thats my take anyway.... :teeth
I agree with you re the tyre pressure. Metzler actually make a BM profile tyre a little rounder than say a Michelin. Suppose to help the steering a little. I prefer my front tyres a little softer, say 36-38 psi and I don't use the Metzler.
Wooden refers to the strange hard feeling of the front end with the Telelever. There have been complaints of the lack of feel on the brakes as well. I don't ride the BM for the sportsbike sensation (I have another bike for that) but I do like to have a bike that steers a little easier.

Actually, the main reason for buying the bike is to make the pillion comfortable and encourage her to join me on rides. Have tried other "sportier" bikes but she will now not sit on anything except a BMW. The K1200GT is heaps lower than the R1100S and being short in the leg department, a Boxer Cup (my last BM) was to tall, especially after recent back surgery.

Every bike is a compromise so just looking to move the bike a touch closer to what I enjoy riding.
 

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This is what your wife will like....no more pogo for me! I noticed the improvement just going down the gravel road from my house. My old(er) back will love them. And I haven't even touched the adjustments yet, something I constantly had to do with the rear pogo. :clap:

And Ohlins are easily adjustable for lenght too by 12 MM.

I tend to wreck BMW OEM Shocks (5) and Driveshafts (3), that is over the last 25 years so please heed the warnings up there. :wtf:

Between that and some new PR2s, totally new bike....! :ricky

Mr. Kiwi has it.....after all he has been suspended properly for a while! :bmw:

 

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Discussion Starter #10
Love the Ohlins!

All things being equal (and they aren't) I would love the Ohlins upgrade but a bit expensive for me at this time.
My TL1000S has the Ohlins upgrade and great for Track and Road.
It is certainly on the long term shopping list.
Enjoy!!! :)
 

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Oz

Yere wasting your time signing in with the Oz bit. Americanos would not know what it means. Smatter of fact not many of them know where Australia is, somewhere in Europe near Germany?
 

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Discussion Starter #12
Oz

Papilio said:
Yere wasting your time signing in with the Oz bit. Americanos would not know what it means. Smatter of fact not many of them know where Australia is, somewhere in Europe near Germany?
Was actually more for the Oz contributors. Gonna be struggling with metric as well!
 
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