Dad needs to know difference between cr80 and cr85

[turbotexas]

I am looking to get my Son a cr85/80 and am trying to avoid getting something he can't race in the super mini class. He has a 96 cr125, but is 13 years old. So He fit's on the 125 but (he's huge) his friends are still in the super mini class, and he wants to race them... I found a cr80 big wheel I am thinking of getting him. I have read the rules on the tire size. but am curious what is the difference is in the two bikes??? besides the 5cc displacement...

Thank you!!!

David

[MattFisher]

The 85cc bikes are just newer bikes that take advantage of a loophole in the rules, just like the 65cc bikes took advantage of the same loophole in the 60cc rules. Originally designed to allow overbore's on 80cc bikes back when every new piston meant you needed to bore it out slightly. Today's bikes have some type of chrome liner instead of a iron sleeve, and are not bored out during a standard rebuild.

The 85cc bikes will be better simply because they're newer, and most get some kind of upgrade every year or so.

[turbotexas]

Thank you Matt!!

What is a big wheel kit? The guy selling is claiming he has that on the bike...

[jd3020]

Big wheel kit consists of 19" front and 16" rear as opposed to 17" front and 14" rear.

[MattFisher]

In addition to the wheel sizes, some bikes will have longer swingarms, and/or longer forks. If he's a big kid, the larger stuff will probably be better.