Compression check

When u do the check i would to know the numbers u get thank u.
just curious why r u doing a check
 
When u do the check i would to know the numbers u get thank u.
just curious why r u doing a check


I recently began hearing a slight miss in the exhaust note like a cylinder not firing right and transmission gear whine changes with the exhaust note. Mostly at very light throttle light acceleration. I am checking vacuum hoses and throttle body seals along with all other adjustments, TPS ect. I thought if I checked compression I could rule out internal engine problems such as valves and I would know the engine itself is ok and the problem is external.it's not a dead miss, more like one cylinder just not hitting the same as the other two.
 
I recently began hearing a slight miss in the exhaust note like a cylinder not firing right and transmission gear whine changes with the exhaust note. Mostly at very light throttle light acceleration. I am checking vacuum hoses and throttle body seals along with all other adjustments, TPS ect. I thought if I checked compression I could rule out internal engine problems such as valves and I would know the engine itself is ok and the problem is external.it's not a dead miss, more like one cylinder just not hitting the same as the other two.


Have you tried crimping the low side of the coils. They do loosen up. I was having a slight miss and that did the trick for me. No effort at all to pull them off, but the front coil was a ***** to get back on.
 
Have you tried crimping the low side of the coils. They do loosen up. I was having a slight miss and that did the trick for me. No effort at all to pull them off, but the front coil was a ***** to get back on.

yes, that was the first place i started. In the past I made a change to the wiring of the front coil. I made an 8 in short harness soldering one end of the wires to the coil terminals and the other end brought out in the open and plugged into the original coil primary wires. Easy to check the connection on front coil now.
 
I recently began hearing a slight miss in the exhaust note like a cylinder not firing right and transmission gear whine changes with the exhaust note. Mostly at very light throttle light acceleration. I am checking vacuum hoses and throttle body seals along with all other adjustments, TPS ect. I thought if I checked compression I could rule out internal engine problems such as valves and I would know the engine itself is ok and the problem is external.it's not a dead miss, more like one cylinder just not hitting the same as the other two.
 
Ok, so finally I have the chance today to get back to working on my bike. When doing the compression test I have one plug out of each cylinder and one plug wire grounded from each coil. When cranking over I have the throttle wide open but the secondaries stay closed. Also it won't turn over at at regular cranking speed. If I hold the starting button in the engine will turn over one stroke at a time with a pause between each cylinder like I'm letting the button off but I'm not. What am I doing wrong?
Ridefree
 
You have the removed plugs grounded or the HT lead from coil to plug grounded with no plug in it?
Or one of the spade connectors on the coil input side grounded?
 
All HT leads are removed. For each cylinder I have one plug removed. The plugs are inserted into the corresponding removed HT Leads and hanging on the side of the engine. I have a ground wire on each plug with one end wrapped around the threads and the other end under a screw on the frame
 
Secondary plates will only open in gear. You might try putting it in gear and turn it over with the clutch pulled in to see if they open. Or just pull them they are easy to pull and put back in.
 
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