i have an 02 that one of the carb slide pins came out of and got sucked into the motor causing quite a mess. the machine shop cleaned up the head and luckily there was no damage at the valve seats just some pits in the dome. did a valve grind just to be sure. we replaced the piston and rings and put it all back together but there was no compression whatsoever - 0. We tore it down again looking for a problem but cant seem to find anything out of place. we are wondering if maybe it could be a problem with the auto decompression setup or maybe the shims need to be replaced now.... any ideas?? Thanks!