Cold Start Problem

[williamemack]

My 1980 R65 starts like a champ in warm weather, but this spring it has been a long grind on full choke to get it going. Seems to run on only one side for a few seconds. Once warmed up the motor purrs like a kitty. Battery is OK, both chokes seem to be opening and I blew out the oraface the choke uses in the float bowl. Any ideas?

Also wondering how owners like their Kisan signal minders.

[Bob_Roller]

I would have a look at the ignition system, possibly 29 year old coils, ignition leads.

Electrical connection condition.

The carbs could be 'gunk-ed' up inside, may need a good cleaning.

I had a cold starting problem on my '81 R65, bad dual output coil, and also the starter was drawing too much power, due to lacking lubricant.

It dragged the battery voltage down to where it was effecting the ignition system during starting.

[nhmaf]

If you hadn't stabilized the fuel (Especially if it was stored in a warm place) it is possible the carbs are still somewhat gunked up or some bit of sediment has stuck in the carb.    If you're positive that there is good gasoline in the tank and it is clean inside, I'd pour in a bottle of gumout or some sea foam and ride it for an hour and see if there is improvement the next day, if not, then time to do more 'hands-on' debugging.

The adjustments for the enricher/choke in the carb may not be quite right or perhaps the arm isn't moving far enough - do you need to use the choke to start the bike in warm weather?  Do you move the choke lever to the "1st" position or all the way?  I know I've gotta go into the starter on my bike and give it a cleaning/lube as it doesn't seem to spin quite as fast as I'd expect it to, even with a new charged AGM battery.  It does start OK, but the starter isn't as "brisk" as I think it could be.

[R65Guy]

Something simple to check...  when you have the choke lever flipped over to full choke, reach down on the back side of the carbs and pull up the choke lever there.  If you can pull the levers up a bit more then your cable(s) may only need adjusting.  

[drewboid]

full choke is the first thing to check - you do keep the throttle turned OFF when starting don't you? Opening the throttle will defeat the action of the enricher.
do you park on the side stand or the center stand? side stand can cause oil to foul the left cylinder.
Some pull in the clutch to take the load of the transmission off the starter motor.

Sometimes it will take several false starts until it will run with full enricher - then let the enrichicer move back from the spring loaded FULL position to ON. Give a little throttle and then move to OFF.

At least this is what works for me.

[BooG]

I had exactly these symptons! Two things worked for me. Firstly, my battery was approx 4 years old and on its last legs. Replaced it with an Odessey. Compression was OK, so took the whole Choke/enricher apart: cables, lever etc. Took the carbs off and made sure the enricher holes where the correct way around..
http://bmwmotorcycletech.info/bingcv.htm
set it all up again, as well as setting the mixture and a carb balance...
the bike has never run better! Just needed the love!!
 

[Lucky_Lou]

Try taking the float bowls off dry them pore a little fuel or car cleaner down the choke camber (small chamber to one side) see if they both feed back into the main float chamber at the same rate if they dont the chances are the jet in the bottom of the chamber is blocked if so the enricher wont work on that side you will need some fine wire to clear it and alot of patience
Lou

[montmil]

My 1980 R65 starts like a champ in warm weather, but this spring it has been a long grind on full choke to get it going. Seems to run on only one side for a few seconds. Once warmed up the motor purrs like a kitty. Battery is OK, both chokes seem to be opening and I blew out the oraface the choke uses in the float bowl. Any ideas?

Also wondering how owners like their Kisan signal minders.

The BMW choke/enrichener system is actually a small carburetor within the principal Binger. We really don't have chokes on our favorite motorcycle.

I might suggest you pull the enrichener off the carbs and check both the paper gasket and the O-ring on the rotating shaft. The paper gasket has been susceptible to collapsing into the enrichener body and the shaft O-rings just plain ol' wear out.

Unfortunately, the component is on the engine side of the carb so plan on pulling off both carbs.

My '83 R65 start procedure is: 1) Turn on fuel; 2)Pull choke lever to full; 3) Hit start button and smile with both cylinders humming.

The '81 R65 Bings are awaiting the arrival of some bits from MotobinsUK. The enricheners need some love as does the needle and needle jet/ atomizer area. Afterwards, I expect the same start procedure. The "one cylinder hittin' and waiting on the second" is unnecessary with our bikes.

For some DIY support-
http://www.ibmwr.org/r-tech/airheads/carb_rebuild.shtml
http://www.bingcarburetor.com/index.html
http://www.largiader.com/tech/carbs/

For Bing bits-
http://www.bobsbmw.com/catalog/2005_catalog/Air%20Head%20Parts(e).pdf  Download the PDF catalog with a few Bing parts; jets, needles, gaskets, etc
http://www.motobins.co.uk/  All the individual Bing parts you could ask for

Bings are great and simple to work on carburetors. No reason not to get them tuned to proper specs.

Monte
  

[williamemack]

Thanks, everybody. I'll have a go at it to morrow.

Will