Tech Forums > SOHC/4 Bikes

1978F Temperatures

(1/2) > >>

majorzozo:
Hi all,

Bike feels like it is running hot but have nothing to compare it too. Purchased a cheap temperature gun from Harbor freight for $22 and recorded the temperatures from a few areas and was hoping someone at some time could maybe share theirs.  The gun was about 10 inches away from each surface and the recordings were done after a 10-mile ride at all speeds.

Left and right-side valve cover reads 235 degrees.
Frame just above oil tank reads 159 degrees.
#1 exhaust about 4 inches from the head reads 132 degrees.
#2 exhaust about 4 inches from the head reads 139 degrees.
#3 exhaust about 4 inches from the head reads 144 degrees
#4 exhaust about 4 inches from the head reads 122 degrees.

If anyone ever checks please share.  Thanks in advance.  Also, the bike is running terrific and after chasing a hanging idle for some time it is finally behaving like it should.  Not 100 percent sure what fixed it but posting what I did just in case someone is fighting the same battle.

1. Replaced all the seals at the throttle and choke shafts.  Originally it came with O rings on the inboard and outboard sides of Carbs 2 and 3 at the throttle shafts with felt on the rest. I changed them all to felt and coated the felt seals with gear oil.  6 total for the throttle shaft and 5 total for the choke.  Full Carb ultrasonic clean.
2. The #1 Carb pilot jet was bent.  Not sure how that happened but replaced with an original from JetsRus.  35 pilots and 105 mains.
3. Swapped the slide positions.  Swapped #1 and #2 and swapped #3 and #4.  Was going to replace the slide needles but could not find originals.  These were stamped with 15A which I believe is the original Keihin but could only find D313 replacements which is not original.  Placed 2 shims under each needle for a total of 1MM per Carb.
4. The accelerator pump spring on the top of the quadrant was just not strong enough so replaced with one from the hardware store.  Squirts much better.
5. Timing, this is the tricky part as the bike has been timed the way Dyna states which is to time it to the advance marks with the pick-up rotated full clockwise.  The bike ran OK like this but never really idled well.  After much trial and error, the bike idles and runs great with the plate rotated full counterclockwise.  Not sure why but the bike starts with full choke, after about 3 miles you can push the choke full in and it runs great including idle at about 1100.  I finally feel that the bike is behaving like it should with the exception of the unknown temperatures.  Thanks for reading.                   

denward17:
I do know my exhausts run hotter than that, but after a 20-30 mile run.
Not sure about the valve cover ends.

Will have to wait a while for me, we are in the dead of winter and it's cold outside.

86FJNJ:
What was temperature outside?  Those temps don’t seem high to me. Most engines need to be above 212F to burn off moisture and generally need to stay under 250F.

It’s an air cooled engine so it will cool when riding over 15mph and temp will rapidly go up when standing still, like at a stop light.

What type of oil are you running?

BenelliSEI:
Those temps seem OK to me, but I’ve never measured them. We have 2’ of snow here right now, so may be months before I can check one!

majorzozo:
Thanks all for the comments.  To answer, the temperature here today was 81 degrees (Indio, CA).  I use Bel Ray EXL 20W-50.  Greatly appreciated.   

Navigation

[0] Message Index

[#] Next page