Chain ring compatibity

[Jro3]

I have an older(vintage) bicycle, it,s a 7 speed using suntour radius parts. I want to change out my chain ring. Some say compatible with 9 or 10 speed, does it really matter? If I buy the same rings as 52/42 with the right BCD.

[Joe_W]

In principle it should work. I was using a 9spd Campagnolo crank set on an older road bike with a 6sp Helicomatic hub. It worked. Sometimes you might need to run a narrower chain. I'd give it a shot, and if the chain makes a racket you use a narrower one. You should replace chain and cassette at that time anyway...