[giles26]

i have recently been looking to bore my 400 out but i cant decide 416 or 426 cause i race flattrack and tt and i put a stage 2 hotcam in it which gave it quite a bit of power but i need a little more and i was thinking the 426 would be good but i dont want it 2 overheat or have to get better valves cause i still trail ride just wondering if anybody has had one and liked it or had troubles thanks

 

[69quadracer]

not a lot of differance in the two go with the bigger if you are going that route

 

[joeylowthers450R]

69 is right, theres not alot of difference.
but i have run both setups in the past and the 416 kits stayed alot cooler when pushed in a race
just my $0.02

 

[chaas5010]

I have the 416cc87mm and i have no complaints i bought it this way so i dont have anything to compare it to other then its way faster then my 300 ex was!