Derbi Atlantis Loooooow compression

[humanshield]

Working on a Derbi Atlantis 2T

First time I ever set eyes on a Derbi.

Where's the starter?   I think it was removed on this one.


Checked compression using kick starter....40 psi

Throttle wide open.  Kicked and kicked and kicked.  Could not get more than 40 psi.

Hole in piston?  Looks like there was no 2 stroke oil in there.

Probably needs a jug and top end kit.

Opinions?

[90GTVert]

At 40psi there's no sense trying to diagnose it without pulling the top end apart unless you pull the head off and it looks great but appears that the head gasket was totally blown out or the plug threads are jacked up. If you think there was no oil then check out the oil injection system if it's still intact and verify that it can still move oil. Look for issues with the crank and conrod and their bearings as well. Look in the manuals section for Derbi and Piaggio manuals.

[niz76]

  What year is that Atlantis? If it's 2003 or newer it probably has the Piaggio engine which is top of the line! Here's my Derbi Atlantis thread:  49ccscoot.proboards.com/thread/11056/flip-derbi-atlantas-piaggio-power



The starter should be on the bottom of the engine (if it's a Piggy)