1988 yz 80 help

[1988yz80]

i have a 1988 yz 80. it has low compression but will run if i push start it.. wat is it the best way i can fix this. i was thinking new rings.
also... the rear shock sags to much and is not very stiff. i can not figure out how to adjust it.
any ideas are welcome i want to make this bike fast. so any thought on how twill be will be read

i am new to here so if u guys could help me out it would be great

 

[2strokerfun]

New rings might fix it but you might also need a new piston and also need to check and measure the cylinder for size, condition and roundness. But your diagnosis of a new top end is probably correct. It could be as simple as a new head gasket or a loose spark plug, but I doubt it. On the rear, you can maybe adjust the preload on the spring to a stiffen it to a certain degree (I'm not familiar with '88 YZ80 shocks--usually a ring on top of spring that can be spun to compress or decompress load on the spring), but more than likely also need to rebuild and charge the shock. You can buy a new one or have yours rebuilt. Could be as simple as a seal, fresh fluid and nitrogen charge. But it could be as bad as a worn shaft, requiring more work or replacement. Check around at shops or on the internet for shock rebuild prices or replacement shock. Good luck.

 

[1988yz80]

im going to buy a new rear shock. the one on mine needs rebuild. i cant find where to adjust it.