Compression number???

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panhead1953ohv
Posts: 13
Joined: Mon Apr 26, 2010 4:49 am
Bikes: 1953 FL
1972 XLCH
Location: twinsburg

Compression number???

#1

Post by panhead1953ohv » Wed Jun 16, 2010 4:59 am

just did a compression check on my bike and got some not so good number 80 in the front and 40 in the rear.the bike has been sitting for over 2-3 years and just put new pushrods in four months ago,i blead the lifters before installing them,bike ran good when stored and i put oil down both cyl every two months.my question is since the lifters are not pumped up will this cause the low readings or??? motor is not stock less then 3000mi 80in strocker 8.5:1 and fl cam.



Saintly
Posts: 52
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knuck repro
98 STD Pan
53 FL
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Re: Compression number???

#2

Post by Saintly » Wed Jun 16, 2010 12:32 pm

are those #'s with the throttle wide-the-F***-open?

If not re-do with WFO. My numbers are real low too(60-70) if throttle is closed, but jump up to 130 when carb is wide open.



PS. I run solids on all my stuff, hydros are voodoo to me. good luck.

panhead1953ohv
Posts: 13
Joined: Mon Apr 26, 2010 4:49 am
Bikes: 1953 FL
1972 XLCH
Location: twinsburg

Re: Compression number???

#3

Post by panhead1953ohv » Wed Jun 16, 2010 2:46 pm

yes that is wide open with both plugs out

steinauge
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Re: Compression number???

#4

Post by steinauge » Wed Jun 16, 2010 2:57 pm

If the engine will start I would warm it up and repeat the test on a hot engine.If possible use a different gauge.If the engine starts easily and seems to run OK chances are you have more than 40 pounds of compression. :)

panhead1953ohv
Posts: 13
Joined: Mon Apr 26, 2010 4:49 am
Bikes: 1953 FL
1972 XLCH
Location: twinsburg

Re: Compression number???

#5

Post by panhead1953ohv » Wed Jun 16, 2010 4:02 pm

the comperssion tester is pretty much top of the line,bought it from a snapon truck when in school it works great,also used it on other bikes a few days ago and was right on so its not the tester.i cant start the bike, points and condensor are bad and waiting on new ones to come.i am going to talk to one of my instructors from school and see what he thinks.

panhead1953ohv
Posts: 13
Joined: Mon Apr 26, 2010 4:49 am
Bikes: 1953 FL
1972 XLCH
Location: twinsburg

Re: Compression number???

#6

Post by panhead1953ohv » Fri Jun 18, 2010 6:37 am

I DONT have to worrie any more about this issue any more,just got the bike started and now have new issues to deal with like oil pressuse light staying on when running.this could just be me wiring it the wrong way but i think its a little more then that.when i run it over the weekend i willl take one of the oil lines off the head to see if oil is pumped out,yes i have outside oilers.

King
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Re: Compression number???

#7

Post by King » Fri Jun 18, 2010 3:59 pm

Taking off the oiler will work but be messy. I just open the filler on my oil tank and watch the return.

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