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02 R1150RS New Fast idle cable fitted and problems

sterob

New member
After having some success adjusting my fast idle cable with a 'spacer' as per Roger04RT's comments, I managed to get it working 'ok'.
It was an old cable so I then decided to fit a new cable.
Now, it appears as I reduce the slack in the fast idle cable, at the handlebars, to get the correct TPS angle ,all it does is prevent the fast idle lever from moving up!
It seems to be jammed. Didn't think that would be a problem when I replaced it. It looked straight forward enough!
So I guess I am going to have to disconnect both throttle cables again and slide the Bowden Box out to try and see whats going on.( after I have already done a complete re-balance...doh. )

I did look at moving the Bowden box last time, to more accessable location, but gave up after it looked too hard.......I think I may try again! Its a real pain to get to!

I think it will involve at least one longer TB cable....

Anybody done this with relative ease?

Anyone had a Bowden Box 'jam' like this?

Steve
 
Bowden Box relocation

I guess no-one has moved the Bowden box.....no problem. I'll look into it.
I'm going to buy a S/H box so I can use it as a jig to find a better location and also make a cover for it, if possible.
It comes with old cables so I can see if I can replace the short cable with a longer one to get the reach.
I don't want to have to fabricate a throttle cable when I change them next.

Plan is to cut a plastic cover using a cnc router, once I draw it. ( thats the hard part....its a weird shape!)

I the future I plan to remove the servo asssisted brakes, as well, so if/when I do that I will have plenty of room for the box.

Steve


Bowden Box 3.JPG
 
Can you tell what's wrong with the one you removed?

I don't know yet as I don't have it out.

I've done something to it when I fitted the new fast idle cable but don't know yet.
The curved metal plate in the lever assembley fell out but I'm pretty
sure its in the right way. It apears that the bowden box will not move when the fast idle cable is tensioned.....I need a few hours of unterrupted time to look at it......

As far as the buying another bowden box, I just wanted a S/H one to use as a jig for a cover and to find a possible new location( $25 with all cables ) , so I don't have to pull the OEM one out and I can still ride my bike.
Its just the way I like to do things......a bit OCD I guess...lol.

Steve
 
Pulled my Bowden box out today and found out how the fast idle system works.
For those that have not dug in this far, the sliding plate has a ramped section that slides along a nub on the underside of the Bowden wheel
that, when the fast idle cable is pulled rotates the bowden wheel a few degrees, so accurate cable adjustment seem crucial, to get enough rotation. ( difficult to photograph to show what I mean. )
Mine was not working and must be due to poor cable setup, as I have a new fast idle cable.

Bowden 3.JPG

Still looking at a possible location change for the Bowden box but not sure I will be able to gain enough lower cable length to achieve it yet.
The 'long' lower ( RHS) is not alot 'longer'.....(60 mm? )

Have also started drawing the outline of the Bowden box in cad, for a possible perspex cover.... I'm thinking it will be easier to see whats going on with a clear cover...

We will see...
Steve

Cover.JPG
 
I guess no-one has moved the Bowden box.....no problem. I'll look into it.
I'm going to buy a S/H box so I can use it as a jig to find a better location and also make a cover for it, if possible.
It comes with old cables so I can see if I can replace the short cable with a longer one to get the reach.
I don't want to have to fabricate a throttle cable when I change them next.

Plan is to cut a plastic cover using a cnc router, once I draw it. ( thats the hard part....its a weird shape!)

I the future I plan to remove the servo asssisted brakes, as well, so if/when I do that I will have plenty of room for the box.

Steve


Hi Steve,
I posted a video years ago on the Bowden Box after a lively discussion on whether it was a "Choke" (it is definitely NOT in the traditional sense) and also whether it only moved the TPS (Throttle Position Sensor) and not the butterfly valve of the throttle body which is definitely does.
I was trying to make it clear that what the misnamed "Choke" lever does is simply advance the throttle slightly to attain a higher idle. Fuel mixture richness is determined by several sensors including the TPS, O2 sensor, air box temp sensor, engine oil temp sensor and the fuel map. I will PM you a link to the video I posted here. Photobucket has taken all the photos and videos everyone posted here and on ADV for ransom and will not allow us to link to them from a forum so they've all disappeared from previous posts. Now you have to pay and join so others can see stuff from this now monetized "sharing" site...

Anyway, by now you've figured out that the Bowden box is indeed difficult to remove but once you do you have discovered the little tab that needs to be pushed down on the metal cage that the Bowden box is held by. You move a couple of hoses out of the way and pull it out. Pretty sure we took mine out on the right side of my 1100RT but no matter, they are all pretty much in the same location.

I would not move the Bowden box to another location for several reasons. It is designed to be there to achieve proper leverage for one thing and also to accommodate the correct cable lengths designed to fit exactly to that location. You're going to end up with a Bowden box that does not work the way it was intended and needing custom length cables. This is a part that virtually NEVER causes problems because it is so simple.

I think what has happened here is maybe two problems. One is that the cables may not be routed properly from the handle bars to the Bowden box. The other (more likely) is the free play before the cables engage is not set properly. If the clearances are not right the Bowden box will not function properly because the free play in either the fast idle cable or the throttle body cables is too loose.

From the 1150 factory manual:
Up top (start here)

• Push back rubber cap (arrow) on throttle and
choke cables.
• Use the adjusting screws to adjust play of throttle
and choke cables.
Choke cable free travel:
........................................approx. 1 mm (0.0393 in)
Throttle cable free travel:
........................................approx. 1 mm (0.0393 in)

Down below (next) This includes what to do when you are synching the throttle bodies.

• Turn the adjusting screws to adjust the play of
the cables for the left and right throttle valves.
Throttle cable free travel:
....................................... approx. 2 mm (0.0787 in)
• Connect hose of BMW Synchro to vacuum
adapter and connect cables to BMW MoDiTeC.
• Start the engine.
Attention:
Do not allow the engine to idle for longer than is necessary, because the trim panels near the exhaust could be damaged.
• Adjust idle speed by turning the air bypass
screws while checking that the carburettors are balanced.
Idle speed: ........................................ 1,100 ±50 rpm

Note:
Make sure that both throttle valves are closed.
Attention:
Do not tamper with the sealed stop screws of the throttle valves, as otherwise the idle-speed volume flow will have to be reset by the manufacturer
• Carefully turn the adjusting screw of the left throttle valve and reduce play until the reading of the
Synchro tester changes.
• Turn the adjusting screw very slightly in the opposite direction until the reading returns to its
original value.
• Tighten the locknut to secure.
Note:
Make sure that the reading does not change when you tighten the locknut.
Adjust throttle cable play at throttle valve so that no play is perceptible, but the throttle valve reliably contacts the stop screw (no strain on cable).
• Adjust the right throttle valve in the same way.
Note:
Zero play can cause the throttle valves to rattle.
• Use the adjusting screws (arrow) to adjust play of
the throttle cables.

Play of throttle cable:
approx. 0.5 mm (0.0197 in)
• Push the rubber cap into position over the adjusting screw.
 
Throttle body cable adjustment to spec is critical in correct fast idle operation. Too loose and you will get very little or no rpm increase.

You are aware that the fast idle has 2 positions - right?
Maintained 1/2 way & lift/hold for even higher starting rpm.
 
Throttle body cable adjustment to spec is critical in correct fast idle operation. Too loose and you will get very little or no rpm increase.

You are aware that the fast idle has 2 positions - right?
Maintained 1/2 way & lift/hold for even higher starting rpm.

Yes, I am seeing how important setup is.
I've ordered new cables and will re-do the setup again.

Will refit B/Box to original place for now( damit!) so I can ride. Still might see if I can fit a cover to keep most of the dirt out, if it can be made to fit and not get in the way.

May revisit at a later stage.....maybe.

Might bite the bullet, later and fab new longer lowers and note the dimensions so I can make copies, so I can mount the box where I can see it with just taking the seats off, and not the tank.

Am aware of the two positions of the lever, as you describe. Originally I wasn't, as mine has always held at the 2nd position, and not dropped back to the 1st position....
Thaks for all the input guys.
Steve
 
Throttle cable free plays

I've read the set up write up's posted here and else where and Ijust want to clarify somemthing please.
I seems that the the lower cables are setup with 'zero play' and the upper cables are set to 1.0mm play? correct?

I am inclined to have 'some' play at the lowers ( 0.5mm? ) just to be sure they won't 'pull' when I turn the bars..... and maybe 0.5 to 1.0 mm play at the upper adjustments, depending on how it feels when I'm done.

I'm aware 'any' play in the lowers will reduce the corresponding travel available from the fast idle cable.....but surely 0.5mm won't matter that much. I'm sure I've had way more then that in the past and that is the reason I have not been able to obtain anywhere near +2° opening at mid detent.
I'll be using Vac Gauges to find the zero points.

Steve
 
If you follow these procedures your fast idle will work correctly as will your throttle body synch. The problem is virtually _never_ the Bowden Box. The tolerances are tight and yes 0.5mm matters because the other non adjustable tolerances also add up in this equation.

Throttle 1.JPG

Throttle 2.JPG
 
I am inclined to have 'some' play at the lowers ( 0.5mm? ) just to be sure they won't 'pull' when I turn the bars..... and maybe 0.5 to 1.0 mm play at the upper adjustments, depending on how it feels when I'm done.

The lower cables go from the bowden box to the throttle bodies. Provided there is sufficient free play in the upper cable turning the handlebars would not in any way alter the distance from the box to the throttle bodies.
 
Bowden Box Cover

A small sheet of 1.5mm lexan arrived yesterday, so today I cut out a cover for the bowden Box.
Its not completely dust/water proof but should keep most of the crap out.
I'm planning on remving the Servo/ABS unit so I may yet relocate the bowden box to that location...not sure yet. It *should* still fit the originl location though...yet to try...
Steve

Bowden Box Cover.jpg
 
Really not sure why you are doing this. You can see everything you need to know right now by pulling the throttle and "Choke" cables and watching what the pulley does. Once it is in the cradle having a clear cover won't help. I am pretty sure the view you have now in your picture will be upside down...

As long as the pulley can move easily without sticking and there are no other obstructions and also your cables are not worn out (stretched) the only other thing is cable installation path and clearances. This assumes the throttle bodies themselves move freely. This is easily tested by removing the cable from them which is really easy. Just pop out the retaining clip on the spool and move it to and fro with your fingers. There should be little to no resistance.
 
Your thinking too much. I am just trying keep the internals as clean as possible for as long as possible.
Having one side of the case open , does not help that cause.
 
Do a search for Bowden Box failures, problems etc. and see what you come up with.

I was talking about this thread with a local mechanic of some renown and he brought up a good point. Once you relocate the Bowden Box what cables do you plan to use from the box to the throttle bodies? The old ones are made specifically to fit where the box is now. So you'll be perhaps the only guy in Australia with custom lower cables.

I may be over thinking it sure... Let us know how it all works out.
 
Do a search for Bowden Box failures, problems etc. and see what you come up with.

I was talking about this thread with a local mechanic of some renown and he brought up a good point. Once you relocate the Bowden Box what cables do you plan to use from the box to the throttle bodies? The old ones are made specifically to fit where the box is now. So you'll be perhaps the only guy in Australia with custom lower cables.

I may be over thinking it sure... Let us know how it all works out.

Thanks for you comments.
Yes, I am aware of the annoyances of having custom throttle cables and I will avoid that if I can. I am just going to explore all options.

I did fabricate custom lowers for my R100RS many years ago when I fitted Delorto's to it and I never had a failure on a few years. I ended up swapping them back out to sell the bike.
I've even considered using 2 RH lowers to gain some length but have not test that yet.

Once the ABS unit is gone, maybe the Bowden Box will sit just above its original location and no cable mods will be required....will let you know what transpires.

Steve
 
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