To leave my balls in my car all week (in michigan cold), then take them inside the day before using them so they thaw out completely before league? Or will that hurt them the same as taking cold balls and throwing em down the lane?

This after I watched Farce of the Penguins last night!

My understanding is that this still makes the balls vulnerable to core separation. The coverstock, core and weight block are all different materials with different densities and different rates of expansion and contraction. If the materials repeatedly expand and contract, the ball can be damaged inside without necessarily showing it on the outside.

Anybody care to confirm this? I'd love to hear something more definitive.

I would not recommend this. The fluctuating temp can cause the core/coverstock to expand and contract. This happens too much and the core can separate and you can also crack the surface.

I also had a ball that had permanent discoloration (white swirls) because of leaving the ball out in my trunk.

High and low temperatures are bad for your bowling balls. It is best to never leave them in the car. You could very well crack the cover stock or severely damage the core. If you leave them out in the extremes then say you brought them inside and go to use them and they've lost a step somewhere. It's most likely your core has separated and you just created a 15# or so paper weight...

I have those on a couple where I left them in my trunk. I was more worried about the core than anything.

My concern is that there had to be some sort of chemical change to the ball. I can't imagine that's good.

I know it's bad but I'm lazy. I'd have to carry my 3 ball bag up 2 flights of stairs so unless the temps are EXTREME they stay in the truck. I've never had a ball crack or a core seperate. Now that I've said that it's bound to happen.

I try to tell my friend this, but he'll leave his bowling balls in the truck year round unless he needs room in the back seat for people. Other than lifting it in and out of the seat every day that he bowls, it wouldn't be hard for him to do it. He has a couple of 4 inch step ups go get into his door. I take mine in and out almost every time, seeing as I have a single cab pick up truck with nothing covering the bed and sometimes have a passenger. I'll occasionally leave them in there for a day or two but normally at the times when it stays between 50 and 70 degrees. The only ball I've ever had cracked was one that sat in my climate controlled basement for a few months and I went to grab it to use and it was cracked all the way around from one side of the thumb to the other.

I used to leave mine in the back of my truck also. I started taking them out everynight, but I would leave one ball and a pair of shoes just in case I had time to bowl a quick game or two without going home. One day I went to grab that ball and it was comepletely cracked. I'm glad I dont leave them inside the car. Its a risk I dont wanna take, so I lug them up the stairs.