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58fleetside
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McKinleyville, CA
Joined: 07/16/2006
Posts: 3

I just purchased a '74 R60/6, my first BMW. I need to ride it 30 miles to my home. The idle is so low it will not continue running without throttle. Is there a quick adjustment I can make? It would be nice to not have it die at every stop I come to on way home.

Thanks,

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Stephen

Darryl.Richman
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VBMWMO #6285
Surf City, USA (Santa Cruz, CA)
Joined: 10/27/2006
Posts: 2185
New 1974 R60/6 needs idle adjust to ride home.

Let's start with the simplest possibility. If the bike won't idle when cold, are you using the choke? There's a thumb lever on the left side of the motor housing, towards the back, near the left air tube. Press this down and then run the bike. It should idle with this on, but will run rough after it starts to warm up. Then the bike should idle with the lever returned to its upper position.

Unfortunately, I'm not familiar with the R60/6 specifically. It seems to me that this bike has slide carbs, rather than the CV (contant velocity) carbs that most of the BMWs of that era had. Because of that, I can't tell you specifically what to look for in the following discussion.

There should be an idle stop screw and an idle mixture screw. The former limits how far down the slide will fall; the latter adjusts how rich the mixture is. Usually the mixture screw will have a lock nut and the stop screw will be knurled and have a spring to keep its position.

When you screw the stop screw in, it raises the slide, which will tend to make the motor run faster. When you screw in the mixture screw, it richens the mixture. Both screws will have an effect on the motor with small portions of a turn.

I would try screwing in the idle stop screw about a quarter turn. Then screw in the mixture screw until the motor runs faster, then slower. When it slows a bit, back the screw off, until it's on the richer side of the fastest idle speed.

On the other side, follow the same adjustment procedure, but you want to get the bike to run evenly on both sides. You should be able to hear the difference in sound from both mufflers; one side will sound like it's working harder than the other. Adjust until they are working evenly.

Then, loosen the lock nuts on the throttle cable adjusters on the carbs. Screw the adjusters out until there's an equal and tiny bit of play in both. With the motor running, and an assistant turning the throttle very slowly, you should be able to hear from the mufflers if one side is lifting off before the other. Once adjusted, tighten the lock nuts

Get the motor warm before you do this. Once you are working, stop the motor after only a few minutes of idling. Don't let it idle for a long time, unless you put a fan in front of the cylinders.

Good luck!

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58fleetside
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McKinleyville, CA
Joined: 07/16/2006
Posts: 3
New 1974 R60/6 needs idle adjust to ride home.

Darryl,

Thanks much for your reply. I got the idle set and rode the bike home with no incidents. Well, other than needing to stop and adjust the clutch which was slipping.

When the owner saw how easy it was to adjust the idle he started wondering if he really wanted to sell it.

Thanks again,

__________________

Stephen

Darryl.Richman
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VBMWMO #6285
Surf City, USA (Santa Cruz, CA)
Joined: 10/27/2006
Posts: 2185
New 1974 R60/6 needs idle adjust to ride home.

Glad I could be of assistance!

BMWs are machines with a certain amount of subtlety engineered in. Things are generally simple -- except for one or two aggravating things! -- but usually require some "inside knowledge"or experience.

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VBMWMO Webmaster,--Darryl Richman
http://darryl.crafty-fox.com

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