what is the BEST bore for MX 416? 426? 440?

[NTPRacing#19]

I want to know what is the best bore for MX. I know how to build up the motor right so i dont need help there. ijust need to know from you guys who race them and have competed against these bores, what is best. IM looking for strong bottom end and midrange but with out sacrificing anytop end. thanks

[DarkStarRacing]

416

[Evan]

Without a doubt the best motor for MX is the 425 with a 13:1 ratio. I have talked to several engine builders and they say this is the best, they run it in TT and MX Now unless you put a carillo rod in it, some say its not reliable, me I have not had trouble, I race only MX so its not seeing high RPMS also I dont have one of those rev boxs that are likely to blow your motor. But if you want reliability and good power go with a 416, with a 12:1 ratio. I see 416s walk over 440s at the track I race at, and yes they are identically setup too IE: TC440 vs TC 416.

[NTPRacing#19]

yea im thinkin about a 416 kit with all the right mods to walk all over some 440's. ive ridden a 416 before and it was so strong and the guy said it was runnin like **** cause it had a little less compression due to a gasket leak. So i can imagine how hard they really pull!:devil

[flying400ex]

A TC416 will not beat a TC440 how whould that be possible? The 440 is bigger and put out more power.

[Derek]

cause it revs faster.

[Sick0]

Yeah I would go with the 416 kit. The 416 will make its power faster than a 440 will. The 440 will end up catching and passing a 416 on a longer staight or some thing.

call tom at tc **** steer you in the right direction and he will tell u that the 425 is the best for the mony out there. it is the biggest bore you can go without having to resleve. but give him a call

[Dave400ex]

Yeah call and talk to different Engine Builders. TC, Sparks, Duncan, Trinity, Powroll, Hetricks, or others I forgot.

Sparks 416 National motor