Hello all, sorry to bother you but i'm having major problems on my k100 throttle cable. I've connected up the mechanism and greased the throttle wheel however their is no tension what so ever on the throttle cable. My k100 is 1984. Does this throttle cable look normal to you ?



Also included a picture of the housing has been greased with molly grease, to me it looks ok. Is there something I'm missing.




Looking forward to replies,
Cheers sam.

On the throttle handle you have thin line marked up, close to the teeth.
You must align this with a arrow or line on the toothed wheel with the chain.

Inge K. wrote:On the throttle handle you have thin line marked up, close to the teeth.
You must align this with a arrow on the toothed wheel with the chain.

Yeah I've done this and tried it all the way around still doesn't want to spring back. It's like too much cable is in the housing, I've also adjusted the adjuster which is half way down the cable. Yet this still doesn't give any respite it seems.

That cable with the adjuster half way down is very old, maybe it's time for a new cable?
Is the cable smooth to operate?

It's the springs down at the throttlebodys that should pull the cable back, all of them is present and non broken?

Inge K. wrote:That cable with the adjuster half way down is very old, maybe it's time for a new cable?
Is the cable smooth to operate?

It's the springs down at the throttlebodys that should pull the cable back, all of them is present and non broken?

Can't seem to find a similar cable for the bike it's an 1984 k100 January model, didn't want to risk getting one that didn't fit. The cable is very smooth to operate and at the throttle body end it's all fine. If I take the cable out of the housing and just pull on the nip it springs back easily. I bet it's something really easy that I'm going to kick myself over as well.

Only a later model cable is available nowadays, then you you also must change the lower bracket and a few other small parts.

Have a look at this: http://technik.flyingbrick.de/images/2/25/Gaszug.pdf

There is no spring return mechanism at the handlebar, the cable must be connected to the throttle body before it will self return.

perhaps you could look at the throttle bodies end of the cable ...the bracket off the rear of throttle bodies (that retains the cable )  from memory has a plastic adaptor ...I noted that my bracket had bent somewhat ...which in turn lets the cable go through the outer far too far to get the mechanism to work properly ...a good rebend of that bracket especially the tongue that hold the bracket  at the right angle  got me another 10 mm of cable pulled through the liner ...letting the chain - bevel drive working heaps better



good luck

It also helps if you lubricate the gears in the throttle perch with spray silicone instead of gooey grease. I've done this to my K bikes and the throttle return is much better that way.

I found the problem but I think a new cable is the only solution if you look at the image below there is a bolt that is threaded into the throttle housing. My bike doesn't have this at the moment. Not sure if I'd be able to get one either. I've got an idea that this will take up the rest of the slack, to get the throttle working correctly.

TheJoker wrote: if you look at the image below there is a bolt that is threaded into the throttle housing. My bike doesn't have this at the moment.

That part isn't used together with the cable you have, it's used on later versions.

Inge K. wrote:

TheJoker wrote: if you look at the image below there is a bolt that is threaded into the throttle housing. My bike doesn't have this at the moment.

That part isn't used together with the cable you have, it's used on later versions.

 Damn so that isn't the part I'm missing then. My cable is most probably normal then. I've checked the route of the cable and can't seem any other problems.

Isn't there a screw adjuster in your cable shown in the first post--that metal block that fits into the rubber boot in the middle of the cable.  That would take the slack out of the cable.

from bmw MOA post:
There were three mods that I know of to the K bike cables. The first had the adjuster about 12" down from the throttle. The second had a metal end at the bottom and the adjuster at the throttle on the bars. The third has a plastic bushing down at the bottom (and a different bracket), with the adjuster at the top as on the second one. The reason for the plastic bushing was to keep the cable sheath from becoming a secondary ground for the rubber mounted bars. This is the only one BMW now sells..

kennybob wrote:Isn't there a screw adjuster in your cable shown in the first post--that metal block that fits into the rubber boot in the middle of the cable.  That would take the slack out of the cable.

You would think it would take the slack but for some reason it doesn't I managed to get the bike started today by pulling on that part of the cable.

You didn't misplace this plastic collar/guide by chance...?


It goes here between the split halves of the (early) front brake master cylinder and the lever perch and would surely mess up your cable's tension.


It's part number 32 72 1 451 622 and is about $5.00USD from zee dealer.

Duck wrote:It also helps if you lubricate the gears in the throttle perch with spray silicone instead of gooey grease. I've done this to my K bikes and the throttle return is much better that way.

+100

Two Wheels Better wrote:You didn't misplace this plastic collar/guide by chance...?


It goes here between the split halves of the (early) front brake master cylinder and the lever perch and would surely mess up your cable's tension.


It's part number 32 72 1 451 622 and is about $5.00USD from zee dealer.

That is the golden ticket right there, can't seem to find them in any of the uk dealers. I'll have to ring up tomorrow to have a nosy around. However I noticed yesterday that the actual boot further down the cable has a massive tear in it. With that being the case I think it might be worth in the end to try and replace it. I'd still need that part though hopefully I can find someone with it.

Good to know there's a definitive fix. Keep in mind, with early cable replacement, you'll require the bracket at the TBs and ancillary bits. See the link further back in this thread. The original type cable is as they say, NLA. Unless you can source NOS. They've been updated for yonks. If the cable is in as good a nick as you say, why not just replace the rubber boot? Save a mass of headaches.