What should the compression be on a Harley?
This engine, for instance, should have no less than 90 lbs of compression and the cylinders should not be more than 10% apart from one another. If you suspect that your motor is worn, or damaged; consider a motorcycle compression test before moving forward and disassembling.
What is a good reading on a compression test?
So, as a general rule a compression of 135 PSI or better, is excellent. On the other hand, a compression of 85 PSI or lower, is extremely bad. Firstly, the most desirable situation is that all cylinders, give the same or close to the same reading. In addition, that reading should be, above 135 PSI.
What PSI should I get on a compression test?
But a good rule of thumb says that each cylinder in a mechanically sound engine should have compression of 130 psi or higher.
What should the compression be on a Harley Evo?
If the compression does not increase to within 10% then the valves of that cylinder may require service. Compression test results vary on stock models but, typical rule-of-thumb is a minimum of 120PSI for 883 engines & 150PSI for 1200 engines, but on 2004+ the 1200 engine minimum should be 180PSI.
How do you fix low compression on a motorcycle?
If you discover you do have low compression, the only solution is to replace the leaking part whether it’s the piston, piston ring, camshaft, head gasket or valves.
How much compression should a motorcycle have?
Generally, less than 20 percent is considered acceptable, and under 10 percent is really good. A leakdown tester is a little more expensive than a compression tester, but I’d say not everyone should have one. If you know you’re not going to tear down and rebuild your engine, skip it.
Is 140 compression good?
Is 140 Psi Compression Good? The rule of thumb is to establish compressions ranging from 135 to 160 PSI or above. If a compression of 85 PSI or less is applied, it is considered very weak. The situation most ideal is one in which every cylinder matches or is close to the same reading, and no two give different numbers.
Is 160 compression good?
You should start to worry if one of your cylinders is getting close to 100 psi. Most new engines in good condition compress at around 175 psi. If we look at the example above, we find that the #4 cylinder at 160 psi is O.K. But let’s compare it with the cylinder having the highest pressure level at 175 psi.
Is 170 psi good compression?
You should start to worry if one of your cylinders is getting close to 100 psi. Most new engines in good condition compress at around 175 psi.
Is 175 psi good compression?
Is 120 Psi Enough Compression? It could be starting to worry you if one of your cylinders passes a significant point.In good condition engines, the maximum compression pressure is 175 psi on average.