Power Loss

[Jimmer]

I was just getting aquainted with my " new to me " 1981 R65, 9 miles into my first ride when I experienced almost complete power loss.  I was 3 1/2 miles from home and managed to just get her back.  At first there was a quick loss of power then a surge as if it were coming back.  Then back to very little power.  When I got home I noticed that the RH cylinder seemed much hotter than the LH side.  I checked for fuel at both sides and there were no blockages.  The spark plugs look normal.
Any Ideas?
Jimmer

[fastcataz]

Next time it happens, try opening your fuel cap. The vent could be clogged.

[Semper Gumby]

Hate to be so general but you need threee things for GO: Fuel, Air and Spark.

Start at the beginning of each and go to the end (motor).

+1 on the Fuel cap thing.  It's the beginning of the fuel part!

Good luck,

[Bob_Roller]

I don't know what maintenance you've performed on the bike since you purchased it, but I think you need to look into the fuel system, before you go out again.

If you have not removed the float bowls on the carbs, I would suggest doing so, and see what may have accumulated in there.

Not that it would cause just one cylinder to have issues, but there should be a fine mesh plastic screen in the fitting that the fuel line goes into, that is screwed into the fuel tank petcock.

Check it for clogging, and if it's even there.

I know a lot of riders don't like fuel filters, but I installed one a few years ago, and it reduced the fine debris in the float bowl, and the usually present glob of water in there.

[Rob Valdez 79 R65]

And a quick ignition test is to switch the plug wires.

If the problem moves to the other side...


But carburetor issues often disguise themselves as ignition, so check it, for sure.

[jusgus]

When I first got my 1980 R65, I had a problem when it lost power and began running very rough.  I was able to get home but just.  I was sure that the bike was running on one cylinder.  The problem was a bad plug wire.  I checked it by removing the plug and checking for a spark.  When one side did and the other side did not I swapped wires and found the problem.  It was easy to fix with two new wires.

[Jimmer]

Problem Solved!  It was the spark plug wire.  I found out the ones on the bike were originals!  Thanks everyone, the R65 runs strong again!
Jimmer

[Bob_Roller]

With bikes of this age, and unknown maintenance history, it can be a crap shoot where to go sometimes, to troubleshoot and fix a problem.

Great to hear, it was a quick, and relatively inexpensive repair !!

[Jimmer]

Just an observation.
I changed the problem side spark plug wire first and noticed that the spark was at least 2X brighter on the side with the new wire compared to the spark from the plug with the original wire that still fired the plug.
I have since replaced both spark plug wires and the bike has responded very favorably.  Final conclusion,  What a fun bike to ride!
What a great forum! Thanks everyone!
Jimmer

[montmil]

Jimmer, are you still running the original coil? Besides the OEM wires, if you have the original ignition coil, commonly referred to as the "Crack-O-Matic", you may as well swap out for a Dyna coil before you have a really long walk home.

The original coil is prone to developing tiny cracks that render the coil as a run-not run crap shoot. Inspect closely. See the tiny, circular cracks?



The Dyna gets it done.  [smiley=thumbsup.gif] Check locally on your side of the pond or knock up Rick Jones at MotorradElektrik.

http://www.motoelekt.com/index.html



Monte

[Jimmer]

Thanks Monte,
I believe I still have the original coil and will check for cracks immediately.  I remember pushing an Ossa Pioneer for many a mile many years ago and will heed your advise!  
Thanks,
Jimmer

[montmil]

Thanks Monte,
I believe I still have the original coil and will check for cracks immediately.  I remember pushing an Ossa Pioneer for many a mile many years ago and will heed your advise!  Thanks, Jimmer

I remember the Ossa!  Ossa, she's a bear was one of their advert tag lines. I was on a Yamaha at the time and my motox bud rode a Pioneer. Jeez... that's a l-o-n-g time ago. [smiley=zzz.gif]

BTW, just yesterday I installed a new Dyna on my '83 R65. The pic I sent is of my '81. I originally missed the tiny cracks in the coil because it was dirty! Bike had random ignition issues that went away after the Dyna was mounted.

Monte

[Bengt_Phorqs]

The Dyna gets it done.   Check locally on your side of the pond or knock up Rick Jones at MotorradElektrik.

http://www.motoelekt.com/index.html

Is there a part number for the Dyna coil?  The motoelekt.com website is under construction and apparently not open for business.  I'm pretty sure that I need to upgrade the coil on my R65.

And as for Ossa's they were great Spanish bikes.  I was always a Montessa man myself.  In fact the last new bike I bought was a King Scorpion way back in 1972.

[nhmaf]

Rick's Motorrad shop is undergoing some changes due to switch in internet service providers, etc, but he should be back in business shortly.
I don't know the part number (I also hhave the same Dyna coil) but you want to specify that it is the Dyna BROWN coil if you're running an 81-86 electronic ignition setup. (Impedance is 1.2 Ohms, I believe)

[Justin B.]

If you want to build your own mounts and save a couple bux you can get the bare coils here: http://www.mpsracing.com/products/MSD/Coils.asp

The $130.80 is for two coils so that works out to $65/each.  I figured with 3 riders it would be good to have a spare...