Retrofitting Starter Cover Jumper Post

[markjenn]

As many of you know, on later R-bikes, BMW added a jumper post above the starter motor to provide a way to jump the bike without having to strip all the bodywork to get to the battery.

While I carry an allen wrench that, with some hassle, can remove the starter motor cover to get access, I've been thinking about retrofitting the jumper post to my 99.

The fiche for the starter cover is below:



The same diagram is used for all years, but only 7, 8, 9, and 10 are shown as applicable to the later models. Although I haven't looked at a late-model bike, I assume the 7 bracket simply bolts to the positive terminal of the starter motor. And this bracket provides a horizontal mounting hole for the vertical post to extend up through the starter motor cover. So presumably these four parts, plus a little dremel work to make a hole in the starter motor cover, would update my 99 with this feature.

Has anyone done this? Comments?

- Mark

[Bart_dood]

Thats a good idea, let us know how you get on with the mod, its something I'd be very interesting in doing to my 99 if it all works out.

[island_dude]

I can tell you that this is a dead useful feature. I had to jump my bike one day after leaving the stupid thing in the park setting. It would have been a serious pain in the butt to deal with if the jumper connections wern't available.

[jclark]

That sounds like a great idea!

jeff

[Rapid Dog]

how come there is no #6 on the BOM?
what is that thing?...the jumper post?

[markjenn]

I wondered the same thing - it's not called out on any year of the S, although I didn't look on the GS, R, RT, etc. There is a hole in the cover that looks to be where it would fit, so my guess is that it is some kind of guide for a cable or wiring that is used on different models but not ours.

- Mark

[Bob in Tucson]

I've not done it, but when I noticed it on newer bikes I asked my dealer and he suggested it was a easy retrofit. This was shortly after the thing showed up, so I am not sure that he had actually done one at that point.

[SCOTTinNJ]

my dealer used a long screwdriver to jump my bike once (died on me while on a test ride before i bought it).

[markjenn]

I ordered the parts (about $20) and will let everyone know how it goes. Thanks for the encouragement!

- Mark

[Bob in Tucson]

Thanks Mark, do keep up posted.

[Chris Canning]

www.wuedo.de

[Ole Bike]

Originally posted by markjenn
I ordered the parts (about $20) and will let everyone know how it goes. Thanks for the encouragement!

- Mark

Yes, great idea. let us know as soon as you can establish if it is feasible or not.

The current for jumping is best passed to the dead battery by allowing the jumper to be in place for as long as you can before cranking, not just relying on the current which passes during cranking (which hardly compares with the heavy current passed at low resistance from the near-dead battery to the starter system).

Easy to keep an auxiliary outlet available by wiring from battery terminals to a connector such as the Battery Tender two-pole connector. Tricky to keep plugs sorted out since one pole is exposed to the air and sometimes this is the hot one and sometimes not if you are mixing and matching current sources (like chargers) and drains (like work lights).

With the stock aux outlet or with the one described above, not hard to bring up a cranked-out (if not entirely dead) battery to cranking status if you have a half hour or so. Even a trickle charger will bring up a battery - even in a car - in an hour or so.

Do the math: 150 Amps (2.4 HP) for 4 seconds is about the same as 3 Amps for 4 minutes.

[markjenn]

Yes, I use the BMW aux connector (that takes the Powerlet/BMW plug) regularly with a Battery Tender. Works fine.

This is really designed to be an emergency/trip sort of thing. Where you come out of your hotel one morning and it's 40 deg and the thing clicks but won't go.

- Mark

[jduke]

markjenn - how did this come out?

[markjenn]

Originally posted by jduke
markjenn - how did this come out?

Got the parts, haven't done it. When it got them, I recall being perplexed about how they'd bolt up to turn the 90 degreees and have the post protrude vertically, but perhaps it will be clear when I do it.

- Mark

[2004 boxercup]

I have contemplated this mod also. This occurred after not riding the bike for a while and all seemed well except that the battery quickly went too low to start the bike.

Common sense tells me the battery would be under the seat and I look. No not there so I call the dealer and they inform me it's under the tank and I might be able to jump it after I remove the starter cover or have it towed.

After calming down and putting the sledge hammer back it its place before taking my extreme aggravation out on the bike I slide underneath and I'm just able to make a connection to start the bike. Later I found out the problem was a loose connection at the starter which must of occurred from the factory.

I've now installed the the accessory port for trickle charging the battery but still curious about how the new start terminal install goes. Had also thought about installing a large gauge wire from the battery or stater to a point under the seat for emergency use with a fusible link at the starter or battery.

Dave

[jduke]

Wudo has a plug solution.
http://www.wuedo.de/indexeng.htm
Scroll down about half way, called their "61 21 20 11 - 13,71 EUR
Socket for the Bikestartset"
You'll also need this part: "Start assistence cable with pliers and plugs" and then the jumper cables that go with it "

[Peter Parts]

A piece of 10 to 14 gage insulated wire attached either to the starter terminal or to the battery plus is all you need. Strip the insulation off the last inch of the loose end and then slip it back on (if you can), until the day you need access to the wire.

Finding a good ground, that's hard. Any suggestions?

Peter

[markjenn]

I just completed the mod. It was easy and looks factory when you're done (see last picture in this post).

The BMW parts you need are as follows (first number corresponds to the diagram at the start of this thread):

(7) 61137671355 Bracket
(8) 61137671354 Screw
(9) 61137672395 Protective Cap
(10) 07119931050 Washer

I don't recall how much these cost as I got them a while back, perhaps $25. Here's what the new parts look like:



Here's the process:

1. IMPORTANT: Disconnect the ground wire on the battery. I know, I know, this means removing all the bodywork to get access to the battery, but this is really not something to fool around with. You're going to be disconnecting a big wire that is ALWAYS hot and unfused, even with the ignition off. (Perhaps do like I did and make this mod when you need to get under the tank for other things.)

2. Remove the allen bolt holding starter cover on and remove starter cover. The bolt is a bit hard to fish out - it's at the rearward end of the cover pointing forward. A small allen wrench and little hands work best. After removing the bolt, iIt helps to push the gear shift lever down to fish the cover out.



3. The stater relay is at the top with the starter motor below. The new jumper post is going to attach to the top terminal of the relay which is wired directly to the battery with heavy gauge wiring. Unscrew the hex nut on the top terminal and push wire aside. Again, if you previously disconnected the battery ground, this wire can touch things without consequence, but if you didn't it's "hot" and will spark like crazy if it touches any ground.

There is a small clip that is inside the wire terminal on the top terminal post - you're going to be replacing this clip with the new bracket piece onto which the post will mount. The bracket has a shape that mimics the shape of the clip. (Gotta love German over-engineering.)





4. Put the wire terminal back on the post and tighten down the hex nut. At this point, you've got a nice bracket ready to receive the jumper post through the starter motor cover.



5. All that's left is to drill a hole for the post in the starter motor cover. I measured, crossed my fingers, drilled a small pilot hole, saw how close I was, and then made a minor correction as I enlarged the hole. Or you might put something in the bracket that would mark the back of the cover when you test fit it. If you want to use my measurements, the hole is 12mm in diameter, and the center is 123mm and 26mm from the left/top edges of the cover. A step drill is ideal for drilling a nice hole.



6. Put the starter cover back on, screw the post in the bracket, and put the protective cap over the post. You're done.





A nice upgrade to those of us still soldiering on with our obsolete old bikes (mine's a 1999 with 43K).

- Mark

[wswartzwel]

Nicely done. Thanks for the tip and taking the time to post your pics for us..



Is that Blood on the frame?