82 BMW 65 LS high idle

[likerobots]

HI All,

Just found this forum, and reading through it, I've found alot of useful advice. Thanks for that.
I am changing my leaking oil pressure sender which is great.
However I have another issue.
Bike has always started great without choke but as of late, its been difficult to start. It takes a lot of tryes and holding the starter down. IN any case carbs were cleaned recently and synced so I dont think thats the issue.
ON an unrelated issue but happened at the same time. When I take the bike for a hard ride, after 15 mins the bike starts idling at 3K . the only way to bring the idles down is to slip the clutch and have it go down to 1.2. But then it starts creeping up.
Any ideas about any of the 2 above issues?

Thanks so much

[Lucky_Lou]

If its been starting with no choke then it could be running rich...does it pop and fart when you shut the revs off? if so thats a sign of rich mixture you may need to re jet it.
Try starting full choke no throttle until it fires then tweak the choke back.
Revs sticking at 3k probably the diaphragms replace them with Bing originals avoid generic versions and stop using fuel additives (if you are)
Lou
ps which part of the planet earth are you from??

[Bob_Roller]

If the carbs were just synchronized, a common problem with high idle rpm's once the bike gets up to operating temperature, is that the carb synch was done on an engine not up to temperature .

You didn't say what year bike you have, but if you have an '81 or later bike, with the single dual output coil, it's a known problematic part, especially if it's the original gray and black version, commonly referred to as the 'crack-o-matic' coil, it could be going bad, causing hard starting  .

[likerobots]

Thanks for the response. guys.
Its a 1982 BMW 65 LS and I live in NYC.
This has started happening lately.
The bike idles great, a bit shaky but very even tick over.
The revs were totally normal  after the carb clean/ sync a few months ago even at full operating temp.

Also apparently the oil pressure sender I got was the wrong one.
Its the wells ps102 but the diameter of the threads is smaller and it has a conical taper after the threads. Pretty strange, I guess i need to keep looking.

[Yikes]

I had a high idle problem on my '82 when the bike was warmed up that turned out to be a timing problem.  Like the carbs, the timing should be adjusted when the engine is fully warmed up.  It's a pretty simple job using the Clymer or Haynes manual.  Just be careful of those hot pipes when you're rotating the bean can (no need to ask me how I know) and be sure you always disconnect the negative battery terminal when you take the front cover off.  I have not always remembered to do this, but have been lucky enough not to cook my diode board the couple of times I've forgotten.

Good Luck with it!

[trolle]

Check the valve settings (0.1 mm on the intake and 0.15-0.20 on the exhaust). The intake is probably OK, but if the exhaust is less than the recommended settings the engine will idle at a high level, especially after a hard ride.

Adjust the valvesettings and if the problem disappears you  have found the culprit.

If the problem reappears after less than 3,000 miles the valveseats are receding and you will have to have new valveseats and valves.

greetings from a grey but dry north, very good riding conditions

[Bengt_Phorqs]

lso apparently the oil pressure sender I got was the wrong one.
Its the wells ps102 but the diameter of the threads is smaller and it has a conical taper after the threads. Pretty strange, I guess i need to keep looking.  

Try NAPA p/n OP6065SB.  I paid just under $8.  Take the original in to the store for comparison.  

[montmil]

lso apparently the oil pressure sender I got was the wrong one.
Its the wells ps102 but the diameter of the threads is smaller and it has a conical taper after the threads. Pretty strange, I guess i need to keep looking.  

Try NAPA p/n OP6065SB.  I paid just under $8.  Take the original in to the store for comparison.  

Can't tell what the NAPA part number is for but if it's a Volkswagen unit, don't use it as the threads are wrong for the BMW bike. It's some sorta conspiracy thing... you need to buy the BMW automobile unit.

Sticky advance weights can cause a high idle. I have found some advance units packed with hardened grease! That's not the preferred lubricant.

Pull the bean can and remove the oval-shaped metal plug located on the side. You'll be able to see the advance mechanism as you rotate the shaft. Check that the two springs are still attached and intact.

Hold the bean can with the front end slightly elevated and position the advance unit where you can see the pivot points. Look for blue plastic bushings.

Hose the pivots with WD40 or similar. Don't use carb cleaner as you may well melt the plastic bits in the can. Rotate to the second advance weight assembly and do it again. Pour out the excess through the inspection port. Shake down any additional cleaner and pour it out or poke a shop towel into the hole just a wee bit and soak up any leftover. You'll likely see very dirty cleaner.

Lightly lube the pivots and the area nearby. I use a machine oil Does not require much lube as the weights swing on nylon glides.

Refit the metal plug, stab the can back in place, then reset ignition timing.

Monte

[Bengt_Phorqs]

Can't tell what the NAPA part number is for but if it's a Volkswagen unit, don't use it as the threads are wrong for the BMW bike. It's some sorta conspiracy thing... you need to buy the BMW automobile unit.

Agreed.  The part number I mentioned is for the BMW auto, not VW.

[Barry]

Get the basics right.

Before trying anything complicated be sure to adjust the idle when fully warm as has been suggested.

There's something about CV carbs that makes them not return to idle easily if idle is set too high. A little bit too high and your into the ignition advance curve which makes for an even higher idle speed and so on...

[montmil]

Get the basics right.

Before trying anything complicated be sure to adjust the idle when fully warm as has been suggested.

There's something about CV carbs that makes them not return to idle easily if idle is set too high. A little bit too high and your into the ignition advance curve which makes for an even higher idle speed and so on...

Barry makes a very good point. Before messing with the borderline worthless outside-the-carb idle screws, revisit the idle tune using the air mixture screws. I set my R65s using only the idle air and keep the idle stop screws just off the butterfly lever.

Monte

[drewboid]

High idle that can be dropped by slipping the clutch is often a sign of sticky weights in the bean can.  As i mentioned before on this board the Omega electronic ignition cured the problem for me. No bean can sensor or ignition module to worry about either. YMMV.

[montmil]

High idle that can be dropped by slipping the clutch is often a sign of sticky weights in the bean can.  As i mentioned before on this board the Omega electronic ignition cured the problem for me. No bean can sensor or ignition module to worry about either. YMMV.

The Omega, and the soon to be released Alpha from Motorrad Elektrik (did you catch the product's segue?), both offer digital advance programs. I do know that the M-E Alpha will use the same Honeywell-branded Hall sensor as does the OEM bean can. Unsure about the Omega. The Omega is approx $100.00 less expensive...

Monte

[Semper Gumby]

What? Rick is releasing his own electronic ignition?  gotta go look....

[Bob_Roller]

Cost is $300US .

http://www.motoelekt.com/alpha.htm

Looks like it just made the OEM 'bean can' obsolete !!

But as it was stated earlier, I'll wait to let them get the inevitable 'bugs' worked out of the Version 1 .