What are the Intamin coasters?

And what are the restrictions on the rides? I read somewhere that Cedar Point doesn't want people who are even slightly overweight riding those kind of coasters.

Plenty of overweight people ride the Intamin coasters. If you fit depends a lot on your particular weight distribution in addition to how much you weigh. Each ride has a test seat outside the queue you can try to see if you fit.

Millennium force 48"
Jr. Gemini, 36" and under 54" or accompanied by a child
Maverick 52"
Dragster 52"
Wicked Twister 52"

RIP
Disaster Transport 46"
Demon Drop 48"

Cedar Point says:
Due to rider restraint system requirements, guests of larger size may not be accommodated on some of our rides. This may apply, but not be limited to, men who exceed 6’2”, or those who exceed 225 pounds, have a 40” waistline or 52” chest or females who exceed 200 pounds or wear size 18 or larger. Each person has different body proportions so it is not possible to list exact size and weight.

Saying "Cedar Point doesn't want overweight people riding" is a bit inaccurate. These kinds of restrictions (mostly set by the manufacturer) are there for a reason.....your safety. They don't build these coasters so they can purposely deny an overweight person the pleasure of riding.

I don't think we need three threads about the same thing.