New guy stuff

[timburn]

Here are some pictures of the new toy. 2 things. At idle the generator light is coming on. Voltage not running,12.6, voltage at idle(1000rpm) 12.29, voltage at 2000- 13.00 and increases with revs. Seems just slightly weak generator output. Barring continues bumper to bumper traffic jams any cause for worry? Second, there is a small 3/4" slit on seat and an edge pulled back 1/8" from edge of seat. If one were broke from buying a bike they shouldn't have, but couldn't live without: would you use a small piece of tape or one of the heating plastic repair kits. Are covers available? They were not around for my last R75.
Thanks in advance
Tim

[Bob_Roller]

Hi timburn, great looking LS !!!!!!!

The  GEN light coming on at idle is normal, this charging system doesn't start to do much charging below 3500 rpm .

If you are in city traffic with a lot of your riding, I'd get a battery tender type charger, otherwise you're going to have low battery charge problems .

I had this problem when i lived in Chicago, if I didn't put the battery on charge, or get it out for a couple of hours at highway speeds on my weekend !!!!!, about 5-7 days of city commuting would run the battery down to the point that the starter wouldn't work .

[bruce_launceston]

http://www.ebay.com.au/itm/BMW-R65LS-1981-85-REPLACEMENT-SEAT-COVER-/370668426869?pt=Motorcycles_Parts_Accessories&hash=item564d8f5675

Nice looking LS, did you know that only 1,713 were made for the USA out of a total of 6,393, that's got to make it a rare beast.

Mine was originally red with silver wheels, is she an '84?

[Barry]

voltage at 2000- 13.00 and increases with revs.  

What does it increase to ?

Ideally you would want to max out at 14.2 or 14.3  That's not likely though with a stock voltage regulator. 14.0 is ok and 13.8 would be the minimum acceptable. Bear in  mind measuring charge voltage like this is only valid if the battery is already fully charged. If it's not you will get lower readings. Also the measurement should be done from cold as the voltage regulator has a built in temperature gradient which lowers the voltage a couple of tenths to take account of the reducing internal resistance of the battery as it warms up.

Before considering megabucks alternator upgrades there is some benefit to be had from fitting a high set point voltage regulator. 14.3 volts or maybe a couple of tenths more more depending on the type of battery chemistry will boost low rev charging but not the maximum output.

I run at 14.3 volts on a standard wet cell battery and the charge light is out at idle although the earlier bikes have a little less current draw from the ignition and I have no permanent headlight load which also helps.

[georgesgiralt]

Also, on a 30 years old bike, clean the wires contacts and ensure the wires are not badly oxydized.
Do it on occasion, when removing the tank for one reason or another.
Remember to disconnect the battery BEFORE removing the front timing cover in order not to fry the diode board or put the bike on fire....

[Luca]

www.motobins.co.uk has your seat cover (make sure to get the one for the LS!) for approx $25 US.  Shipping is always a as they are based in the UK.  You won't know the shipping cost until they have shipped and charged.  If you find yourself building a small list of things you want to get for your bike, it might be worth it to throw a few more things in the basket and combine shipping.

As others have said, the GEN light is normal.  Think of it as a way to make sure you keep the revs up and oil on your timing chain  [smiley=wink.gif]  And you probably know from you last Beemer, but it's worth mentioning in case you dont, if GEN light bulb is burned out, the alternator will not charge.

If you ever get a new battery, I'd strongly recommend a sealed AGM unit.  They can be had for a reasonable price.

[montmil]

I bought a DIY cover from Northwest Classic for my '83 R65. Here's a link to the R65LS cover.

http://www.ebay.com/itm/BMW-R65LS-1981-85-REPLACEMENT-SEAT-COVER-/370668426869?pt=Motorcycles_Parts_Accessories&vxp=mtr&hash=item564d8f5675

Excellent install instructions along with a quality product. I have a photo essay in the Gallery that will help with a few tips.

[timburn]

Thanks to all.Voltage  output at 3000 0nly 3.6/7. May have to look at this.  Will pull all connections and clean up.

[montmil]

Thanks to all.Voltage  output at 3000 0nly 3.6/7. May have to look at this.  Will pull all connections and clean up.

Yup. problem there. You should be seeing an additional 10+ volts reading on the DVOM -at the battery terminals with 3500-4000 revs on the clock.

Start cleaning electrical connections. Start with the battery's negative/ground cable. You'll want that one off anyway as you work your way through the suburbs of CorrosionVille.

Pick up a can of electronic cleaner at Radio Shack. Helpful in cleaning the small male-female pin connectors and the stuff won't melt plastic. While at the Shack, grab a small tube of dielectric grease and add a smear on the clean n' shiny terminals.

You might want to consider checking the two carbon brushes that run on the rotor. When these items wear down to minimums, there is insufficient spring pressure to maintain solid contact resulting in a weak charge to the battery. Diode board terminals should be shiny clean, too.

Usually something simple on these old tractors so check the simple stuff first.

[Barry]

I'm thinking Tim might have meant 13.6 to 13.7 volts as he had 13 volts and rising at 2000 RPM. It's still a few tenths low if it was measured on a cold engine with a fully charged battery. If it was measured at the end of a run with a hot engine then it's not too bad.

[Justin B.]

Barry, remember that Monte is sooo literal!  

If after cleaning electrical terminals your charging doesn't improve maybe check your brushes to make sure they aren't worn down too far.  You can also get an adjustable voltage regulator from http://www.euromotoelectrics.com/product-p/vr-extadj.htm for about $25.