R1200S throttle action

Herb · Post by **Herb** » Tue Feb 12, 2013 1:38 pm

peter f wrote:
Herb wrote:I have not been able to find out for sure but I think the eccentric is in the splitter box. So modifications at the throttle may shorten the travel but you will still have the non linear throttle
Splitter has nothing to do: the (ugly and pointless) eccentric is in the TB's "pulley" thing (2 things actually).

Make a small test: knee near by the right TB and twist slowly the throttle: observe how the cable push/pull motion is translated into a "not linear" rotational action on your butterfly: these things are not moving (i.e. rotating) at all at first and then start following your input. German sense of humor that one ? (or a total ignorance about what a sports bike is).

But this mod mentioned is better than nothing.

Of course the ultimate solution is to fabricate a proper linear action TB "pulley" (not exactly cheap that one).

I will take a look.

f90x · Post by **f90x** » Tue Feb 12, 2013 2:34 pm

Ok, so just to get it straight in my tiny mind. This mod will retain the 'non linear' ecentric pull but shorten the entire action to get to 'full open' throttle. If that's the case I can live with that even though I would prefer a straightforward linear throttle.

David_S_Walker · Post by **David_S_Walker** » Tue Feb 12, 2013 4:34 pm

f90x wrote:Ok, so just to get it straight in my tiny mind. This mod will retain the 'non linear' ecentric pull but shorten the entire action to get to 'full open' throttle. If that's the case I can live with that even though I would prefer a straightforward linear throttle.

Yes.

If you live anywhere near me (NE Kent) - I see you are Norf Lundon (I came from Sarf Lundon) you could have a go on mine when the snow clears. I work in Sarf east London during the day.

Best regards,

David

Droptarotter · Post by **Droptarotter** » Tue Feb 12, 2013 5:21 pm

Herb wrote:Found one.

http://www.boxer-design.de/en/detail.asp?ID=11&pID=1141

I had one of these on my 12S............sold it.

It made a minimal difference........somewhere I have a photo of the degrees of throttle rotation comparing stock with this item.

Try this..........put a dot on your throttle tube and another on the throttle housing where the stock throttle rotation stops.

Now make a mark that is 1cm closer to the closed position...............that is how much the device is going to change the rotation.

I found the part way overpriced for what you get and would only put it on a track bike!!

Get some electrical pvc ( I think) tubing or any plastic tubing that is about 1" in diameter. Cut it so it will look similar to the Boxer Design device.......taper one end, make it just wide enough to fit where the cable rides and under the cable....install.......that will give you about the same "cam" on the throttle tube as the Boxer Design device.

Make lots........everyone will want one.

I think the best way to eliminate this problem is to fit HP2 Sport throttle bodies.......but that might open up another can of worms!!

Cheers

f90x · Post by **f90x** » Tue Feb 12, 2013 9:35 pm

David_S_Walker wrote:
f90x wrote:Ok, so just to get it straight in my tiny mind. This mod will retain the 'non linear' ecentric pull but shorten the entire action to get to 'full open' throttle. If that's the case I can live with that even though I would prefer a straightforward linear throttle.
Yes.

If you live anywhere near me (NE Kent) - I see you are Norf Lundon (I came from Sarf Lundon) you could have a go on mine when the snow clears. I work in Sarf east London during the day.

Best regards,

David

David, that is a mightily generous offer. Thanks very much. The likelyhood of me being able to take you up on it before The end of april is very slim though, so until then could you confirm or Deny Droptarotter's findings re the throttle travel in the hand. How much less do you have to twist the grip in order to get to maximum throttle. Is it comparable to a regular throttle on any other bike?

Cheers
Steve

Droptarotter · Post by **Droptarotter** » Wed Feb 13, 2013 3:51 am

Maybe I should clarify my post...............

The Boxer part will retain the non linear throttle pull, but it will require less total rotation of the twist grip by about 1cm.

F90X...............see how it feels for you to twist the throttle 1cm less than to the throttle stops................that will tell you if you can live with this part or if it will not help.

Cheers

f90x · Post by **f90x** » Wed Feb 13, 2013 7:31 am

Droptarotter wrote:Maybe I should clarify my post...............

The Boxer part will retain the non linear throttle pull, but it will require less total rotation of the twist grip by about 1cm.

F90X...............see how it feels for you to twist the throttle 1cm less than to the throttle stops................that will tell you if you can live with this part or if it will not help.

Cheers

Thanks for that. I'll have to have a look when I'm next visiting my folks (it's where I keep my bike). Unfortunately I'm working in Paris until approx the middle of April and unlikely to get to my bike before then which is why I'm being a bit painful with all my questions.

Cheers
Steve

David_S_Walker · Post by **David_S_Walker** » Wed Feb 13, 2013 7:57 am

f90x wrote:
David_S_Walker wrote:
f90x wrote:Ok, so just to get it straight in my tiny mind. This mod will retain the 'non linear' ecentric pull but shorten the entire action to get to 'full open' throttle. If that's the case I can live with that even though I would prefer a straightforward linear throttle.
Yes.

If you live anywhere near me (NE Kent) - I see you are Norf Lundon (I came from Sarf Lundon) you could have a go on mine when the snow clears. I work in Sarf east London during the day.

Best regards,

David
David, that is a mightily generous offer. Thanks very much. The likelyhood of me being able to take you up on it before The end of april is very slim though, so until then could you confirm or Deny Droptarotter's findings re the throttle travel in the hand. How much less do you have to twist the grip in order to get to maximum throttle. Is it comparable to a regular throttle on any other bike?

Cheers
Steve

Steve,

For me it solved a problem - I have slightly arthritic wrists and was finding my own personal inability to open the throttle fully not as easy as it used to be. This started during my K1200S/K1300S days. This was suggested to me and whilst I baulked at the expense I tried it out and it worked for me. I can now open the throttle fully without a problem. It also seemed a simpler solution than trying to remove the non-linear nature of the throttles. As DropaTrotter points out there is other more cost effective ways but I can only speak from my experience and it worked for me.

As it is fitted I wouldn't be able to quantify the actual difference it made in centimetres/millimetres unless I removed it.

I did sell my K1200S one on to another individual who also found it to be of use.

Maybe its only for older gits only?

Best regards,

David

StreetFlatTwin · Post by **StreetFlatTwin** » Wed Feb 13, 2013 8:23 am

The thing you need to remember is that BMW put the non linear throttle on there to try and protect us from our hamfisted throttle inputs while on wet greasy roundabouts! If you had a direct throttle connection and give it too much (easier with a quick action throttle) the torque from the big twin could spin the rear...and BMW don't want to kill off their riders!

From experience of quick action kits I have always found them (for me at least) to be worth the effort of fitting them. Yes it takes you a week or so to re-calibrate your brain (and right hand) and on off traffic may be a bit more jerky but still always came down on the side of with QA throttle.

I wouldn't mind one and may investigate the cheap options (tubing, cable tie etc) to slightly reduce the throttle throw to one grip twist rather than twist slide and twist again!!

f90x · Post by **f90x** » Wed Feb 13, 2013 12:30 pm

David_S_Walker wrote:
f90x wrote:
Maybe its only for older gits only?

Best regards,

David

As an old git I would have to concur

nab 301 · Post by **nab 301** » Wed Feb 13, 2013 7:41 pm

Stick with an 1100 and save yourself the trouble

f90x · Post by **f90x** » Wed Feb 13, 2013 9:17 pm

nab 301 wrote:Stick with an 1100 and save yourself the trouble

I have an 1100. It's a great bike.

congoman · Post by **congoman** » Sun Mar 03, 2013 8:29 am

Hi all

I wanted to update folks on the mod I posted on the R1200S throttle below:

viewtopic.php?t=14669&highlight=throttle+eccentric

peter f was right in understanding this mod:

Splitter has nothing to do: the (ugly and pointless) eccentric is in the TB's "pulley" thing (2 things actually).

Make a small test: knee near by the right TB and twist slowly the throttle: observe how the cable push/pull motion is translated into a "not linear" rotational action on your butterfly: these things are not moving (i.e. rotating) at all at first and then start following your input. German sense of humor that one ? (or a total ignorance about what a sports bike is).

But this mod mentioned is better than nothing.

In the 3rd picture on page one of the thread you can see the golden reflection of the new part inside the pulley. I guess that it is from another bike in the range.

On the road it means a more direct throttle action. However the throttle is still not completely linear. This may irritate some, but I treat it as a little safety margin. The rear end does spin up more readily after the mod; for example on wet surfaces in 3rd and 4th or in low gears on the sandy crap all over our roads.

I am very glad I made the mod. and it has made the bike for me. It was killing my right wrist over long distance and the mod has solved this.

f90x · Post by **f90x** » Thu Mar 14, 2013 10:52 am

Any news Gus? Did you get the part? If you think it's any good ill order it up as I'm home for good in a couple of weeks and I'd love to get it sorted for Spring.

gus · Post by **gus** » Fri Mar 15, 2013 4:00 pm

Hi
Sorry for the late reply. I spoke to the German shop I deal with and asked them the question. They did not know of any modifications to get rid of the non linear action of the throttle. As for a quick action throttle. The racers would use a different setup on the handlebars using a different throttle tube and housing. They had not used the QA bits for sale . I think the bits to convert the throttle are a bit expensive for what they are and as I have a proper quick action throttle laying about I will try and use that if I can. I want to change the front brake MC anyway, so it may be possible. As for doing the mod at the throttle body end , it will have to wait until I remove the throttle bodies to install some over mods.
Gus