1969 R60/2 not running

[Anthony fish]

I was riding the other day when all of a sudden the motor bogged down and staled. I pulled over let it set for a minute then started it and it ran for a couple of blocks then staled the same way. It seems like it’s getting fuel based on movement in the filter.
The plugs have a spark when grounded to the fins, I’m not thinking the carbs because up till then it was running and idling fine. And what are the chances of both carbs failing at the same time.
One thing I did notice is when I was riding just before having the problem is that the idle would stay high for a couple of seconds then stabilize.
Now when I attempt to start it, the bike starts and Boggs down and stalls right away.

Any suggestions would be appreciated.

Anthony

[schrader7032]

Seized pistons??

[Anthony fish]

The bike turns over and I have pressure at the spark plugs

[schrader7032]

I've never experienced it and don't really understand the phenomenon, but Duane mentions seizure here:

http://w6rec.com/duane/bmw/piston/index.htm

I was under the impression that the piston can seize but then after a bit of time, the bike will run again, until the next seizure. I suspect there's some damage being done with each seizure.

That's about all I could think of initially when you said that you were running along fine and then the engine just bogged down.

Check the simple stuff. Make sure that the air filter hasn't collapsed or is blocked.

[The Plunger]

My first thought was a tankful of bad gas or something in the gas clogging the jets. Did you switch to reserve just before this occurred? Maybe some junk in the bottom of the tank.

[stagewex]

I'm also thinking crap/debris in the gas. Yes, that will affect both carbs at the same time.
And your description sounds all to familiar.
Have you flushed or ever flushed your tank and fuel lines?
Are you running filters to each carb?
Have you personally cleaned and tuned your carbs?

You only need the smallest bit of crap the size of several of your hairs to bog things up.
Lets hope it's something like this and not a seized motor. If you can turn the motor with your foot that is a good sign.

[312Icarus]

Not to belabor the obvious, but have you checked the oil? (Both condition and quantity?). I might lean to a a clogged peacock screen however.

You might also consider the condensor, as they will allow a quick start and then stop!

Icarus

[bstratton]

All good suggestions - and I would check them out but my first guess would be a fuel supply problem. Petcock screen, fuel filter, bad gas, no gas.....

If you decide you may have contaminated gas you will need to remove the carbs and clean them. No big deal but record your adjustment screws settings so you can get close when you put them back together before you re-balance them. Do them separately so you don't mix up parts between them. Sometimes just some carb/choke cleaner and compressed air in the right places will get the job done.

And also if you suspect contaminated gas, flush the tank and replace your fuel lines and filter(s), of course.

Good luck!

[Anthony fish]

It’s strange, I do not think it is a fuel problem because the tank is clean, new gas and plenty of flow thru the gas filters. What I have noticed today after draining and refilling the tank, changing the plugs and cleaning the points is, the bike started up fine and runs great. I allow it to warm up, rev the engine a few times and the engine idles fine with minimal back firing. I ride it up and down the block a few times the all of a sudden it bogs and stalls. I remove one plug to find I have no spark. I think after it cools down the spark comes back. Richard from Bench Mark said it might be a weak or damaged coil.
Any thoughts

Anthony

[312Icarus]

Bad coil, (tired OEM?)or bad condensor sounds good to me.

Icarus