I have an amazing 79 KZ650 that I really like. The bike has had lots of upgrades including pod filters, jetting, and a 4-1 header. The bike is an all out screamer and runs like a top. However, when I get the bike on the highway and the wind is just right it will cut out. Also, if I open my legs up and force air towards the pod filter it also cuts out. Am I getting too much air and messing up the mix. Earlier this year I was on a long ride and had this happen and I blew a hole in the piston. I have since changed motors and had a mechanic go through the fuel and intake system. The bike is tuned and running like new but on the highway it is still cutting out. Is there a fix for this or am I stuck since I have an unrestricted air system?

 

KS, welcome to the forums. I'm not completely convinced the pod filters are the culprit. I've had several bikes of the same vintage with pods, and never had a problem. Are you sure you're not running a bit lean (firstly) and THEN the excess air might cause a problem? Hole-ing your piston tells me you may be getting some early detonation. What do your spark plugs tell you?
Welcome again.
Gear up; stay safe.

 

Jeff:

Thanks for the response. I just had the carbs set and we errored on the side of rich in lieu of lean. We did not want a repeat of the hole in the piston. The plugs are new and have less than 200 on them. I will pull them tonight and see how they look. Other than the issues in open country riding with wind and causing the air to be directed to the intake the bike runs and seems great. We assumed the hole in the piston was due to rust. Carbs have been cleaned, tank cleaned, and inline filter installed.

 

Welcome to KF and maybe keep your legs closed more often? hahaha