Airhead "Tips and Tricks"

[bmweuro]

Originally Posted by daveoneshot

Just got done removing the alloy spacer that hides the neutral switch on my /7, the one the long engine bolt passes through. I used my Cat's Paw nail puller......it's got a perfect hook that you can wiggle over the spacer, then grab the other end with some old Vice Grips and tap away. Took me a while as it was my first time removing this thing, but it
finally came out. Let's call it a Poor Man's Slide Hammer.

If you put a slight bevel on both ends of the alloy tube it goes back in much easier.

[moosehead]

And throw it in the freezer for an hour or 2 and it'll nicely pop back in...along with those bevelled edges.

[MotoKaw]

My old throttle and enricher cables are kinked right above the metal end fitting on the sleve, above the adjustment fitting that screws into the top of the Bing. I ordered new cables from BMW, but they will just do the same thing eventually without some additional "flexible" support.

Go to your hardware store and look through their selection of springs. I used 7/16-inch x 3-inch compression springs from Midwest Fastener Corp. in Kalamazoo, Mich. (http://www.fastenerconnection.com/)* - they just happen to supply my local hardware store. Part #18676 (spring #165 on the board) is what I used, but others would have worked too.

The picture pretty much tells the story. This size spring will slip over the grip end of the new cable, slide down past the kink point (the joint between the cable sleeve and the metal end fitting) to the adjustment fitting, where it will rest on top of the jamb nut. If you aren't replacing cables and don't want to remove your existing ones from the grip housing just to do this simple mod, simply open the crimped end of the spring a bit (like a key-ring) to get it started on the cable, then wind the spring on over the cable -



Finished. The springs cross the kink point and are supported at the bottom by the adjustment fitting screwed into the Bing cover. This will help give some lateral support to the cable sleeve and spread the load over a broader area so it doesn't kink right where the cable sleeve exits the metal end fitting -



Comparatively cheap('ish) protection at $0.90 each.

Good luck,

Bob

* Based on Midwest Fastener's web site I may have to take a ride to Kalamazoo to see this place in person! I'm a hardware store junkie, expecially the 'hardware' isle itself! In the sixth picture down, on the back wall, you can see the kind of spring display that my local store had.

[disston]

That's a nice trick MotoKaw. My throttle cables are also kinked. I'm gonna try that one. Thanks

[Sic Semper Tyrannis]

I split a piece of fuel line about 3 inches long. Slipped over the throttle cables and zip tied with black wire ties.

Works great.

[pthomas]

Originally Posted by MotoKaw

My old throttle and enricher cables are kinked right above the metal end fitting on the sleve, above the adjustment fitting that screws into the top of the Bing. I ordered new cables from BMW, but they will just do the same thing eventually without some additional "flexible" support.

Go to your hardware store and look through their selection of springs. I used 7/16-inch x 3-inch compression springs from Midwest Fastener Corp. in Kalamazoo, Mich. (http://www.fastenerconnection.com/)* - they just happen to supply my local hardware store. Part #18676 (spring #165 on the board) is what I used, but others would have worked too.

The picture pretty much tells the story. This size spring will slip over the grip end of the new cable, slide down past the kink point (the joint between the cable sleeve and the metal end fitting) to the adjustment fitting, where it will rest on top of the jamb nut. If you aren't replacing cables and don't want to remove your existing ones from the grip housing just to do this simple mod, simply open the crimped end of the spring a bit (like a key-ring) to get it started on the cable, then wind the spring on over the cable -



Finished. The springs cross the kink point and are supported at the bottom by the adjustment fitting screwed into the Bing cover. This will help give some lateral support to the cable sleeve and spread the load over a broader area so it doesn't kink right where the cable sleeve exits the metal end fitting -



Comparatively cheap('ish) protection at $0.90 each.

Good luck,

Bob

* Based on Midwest Fastener's web site I may have to take a ride to Kalamazoo to see this place in person! I'm a hardware store junkie, expecially the 'hardware' isle itself! In the sixth picture down, on the back wall, you can see the kind of spring display that my local store had.

Any worry that the cable will be damaged from vibration?

[MotoKaw]

I don't think that vibration will cause the spring to wear into the cable sleeve. This particular spring was of the "Goldilocks" variety - not too stiff, not too flexible, just right.

I'll keep a close eye on it though and report back if it causes more probles than it cures.

That being said, I like SST's split fuel line idea too! If this spring doesn't work as intended that's what I'll do next. Thanks for sharing it SST.

[Wirespokes]

I'd think a closer fitting spring would be better - one that just fits the cable.

[MotoKaw]

Originally Posted by MotoKaw

*** Part #18676 (spring #165 on the board) is what I used, but others would have worked too. ***

You might be right WireSpokes. I took my cable to the hardware store and tried many different sizes. I think that several would have worked well enough, but I went with the 7/16-inch diameter because it had a nice close fit to the knurled screw head and metal end fitting on the cable sleeve (a solid/fixed support point) and then spread a decent amount of lateral support to the sleeve above that end fitting (which is where the kink happens).

An extra thick heat-shrink wrap tube (or a few layers) crossing the usual kink point would probably work too. But SST's fuel line idea and this spring can be moved to make cable adjustments - I think shrink tube would have to be removed, replaced, cables adjusted, then shrunk again to get the same job done.

Bob

[Beemerboff]

The ferrule on the end of the cable unscrews, so it is possible to unscrew it, unwind and cut off the kinked bit, and screw the ferrule back on, but only if you still have a decent bit adjustment in the cable.

Also good to know if you are trying to fit 32 mm cables to 40 mm carbs, some 32'cables have been known to end up in the wrong parts bag- DAHIK.

[Zodiac]

Originally Posted by bmweuro

If you put a slight bevel on both ends of the alloy tube it goes back in much easier.

I need to do this soon, replace my neutral switch. I took a glance at Snobum's comments on this but didn't read the whole thing.

So to do this; once you pull out the engine support rod, and get the alloy spacer out, does the engine need to be lowered or can you just put a jack underneath and support the engine when you replace the switch?

I guess I'm wondering why it would need to be lowered if you can reach the switch port.

[disston]

I think I used some kind of jack the last time I did this. Use a small piece of wood in between the jack and Aluminum.

Sometimes reading Mr. Bum is something you have to work up to. Probably too early in the day.

[Wirespokes]

The reason for removing the spacer is clearance - the switch needs more room and the spacer interferes. The rear of the engine needs to be supported, though it'll be close to balanced on the front one. A jack makes it easier to keep the engine bolt from binding when withdrawing and replacing.

[supershaft]

Kinking throttle and choke cables? I think the real solution is getting cables that are not too long. When they are the right length, there are no forces there to make them kink so they don't. Granted, figuring out what length cable you really need it a PITA but . . . first things first IMO.

[Zodiac]

Originally Posted by Wirespokes

The reason for removing the spacer is clearance - the switch needs more room and the spacer interferes. The rear of the engine needs to be supported, though it'll be close to balanced on the front one. A jack makes it easier to keep the engine bolt from binding when withdrawing and replacing.

So essentially the engine doesn't need to move whatsoever in the frame, only the alloy spacer. You don't need to lower the engine just loosen the front support rod and remove the rear, spacer comes out and swap the switch as per Snobum....