I got a compression test done on my ktm 530 and is losing 20% is that okay

Compression test is read in psi and a leak down test read in % leakage. 20% leakage is not good. with the leak down gauges in place, listen at the carb or end of the exhaust and in the oil fill hole for leaking air. That will tell you if you have a bent valve or broken ring.

easiest fix is to run a non synthetic oil to help the rings sea,l wont seal for about 20 hours of ride time, about two oil changes. The rings and cylinders were hardened for long gevity.

a big YES

Have a compression test done.
Then have a leak down test done.
Blow by is a sign of wear, check it out!

front axle installation: looking at the front of the bike:

slide the wheel into position and insert the axle from the left. with axle now through the right hand fork, install nut and tighten the left fork pinch bolts to secure the axle for tightening the nut. tighten the nut to 29.5 ftlbs. and loosen the left pinch bolts. now tighten the right pinch bolts and compress the front suspension while the left (from front) is still loose. now allow suspension to rest naturally and tighten all 4 pinch bolts to 11 ftlbs.
your done.......the axle is tighten against the rotor side and the other fork is then tighten in it's natural position so as not to cause premature seal and bushing failure and increasing stiction.

A LOT!

KTM does not provide a spec for this. If you think you are low on compression, you will need to perform a leak down test on the motor to determine if work is needed.

If it's a real bugger to kick start, install an 09 cam, works wonders. Go to KTMtalk.com to inquire about emissions removal