HotCarl Posted November 29, 2006 Report Posted November 29, 2006 392 vs. 421 What is the power and reliability difference between the 2? I'm building a duner that might see a trail once a year. Quote
HotCarl Posted November 29, 2006 Author Report Posted November 29, 2006 Go with the 421,There is a big differance in power. :beer: I really don't want a 100hp bike, i just want something to get my fatass around and not have to worry about having enough power. I plan on running a +4 swingarm and I'm affard the 421 is too much power. Quote
bansheeseat$$ Posted November 29, 2006 Report Posted November 29, 2006 Go with the 421,There is a big differance in power. :beer: Quote
bansheeseat$$ Posted November 29, 2006 Report Posted November 29, 2006 I really don't want a 100hp bike, i just want something to get my fatass around and not have to worry about having enough power. I plan on running a +4 swingarm and I'm affard the 421 is too much power. If thats the case you may wantto go with a 358 cub or even a 397 cheetah power valve set up.Plenty of power but not quite a light switch power band. Quote
locogato11283 Posted November 29, 2006 Report Posted November 29, 2006 id still go with the 421... Quote
Bansh-eman Posted November 29, 2006 Report Posted November 29, 2006 a 421 your not going to hit 100hp... do it right the first time and just get the 421... youll thanks your self later... Quote
350shee Posted November 29, 2006 Report Posted November 29, 2006 a 421 your not going to hit 100hp... do it right the first time and just get the 421... youll thanks your self later... a drag motor will hit over 100HP on gas and 115 with alky. for a play bike id go with a 7mm 65 bore you will have plenty of pep and its a 404cc on gas with just a clean up port on it, it will easily be 80hp and thats plenty to dune with fat or not! Quote
bada450r Posted November 29, 2006 Report Posted November 29, 2006 392 vs. 421 What is the power and reliability difference between the 2? I'm building a duner that might see a trail once a year. i have a 421 cub,and the truth is i dont think ill make a good dunner,but man iam so happy with mine,when the power band hits,hold on,and shut up.i duned my cub this past saturday went from the vender flats to olds,and went up the hill 3 times,came back on fumes.[glamis baby] :beer: :: :: :: :: :: :: Quote
Bansh-eman Posted November 29, 2006 Report Posted November 29, 2006 (edited) a drag motor will hit over 100HP on gas and 115 with alky. for a play bike id go with a 7mm 65 bore you will have plenty of pep and its a 404cc on gas with just a clean up port on it, it will easily be 80hp and thats plenty to dune with fat or not! no one said a drag motor wont hit over 100hp but a 421 cub on gas isnt going to make 100hp wothout a fat port job... just runnin a cleanup port on a cub isnt going to get you there...why the fuk spend the money on a 7mm crank to get a smaller motor when you can get a 4mm cub for close to the same amount and have better top end... for a 7mm your going to spend around 1500 just for the crank the cases to be trenched ,a crank and a port job..and you still need pistons or you can get a 4mm cub and spend 1400 and have better topend and still be abe to dune it...and thats for everything i have a 421 cub,and the truth is i dont think ill make a good dunner,but man iam so happy with mine,when the power band hits,hold on,and shut up.i duned my cub this past saturday went from the vender flats to olds,and went up the hill 3 times,came back on fumes.[glamis baby] :beer: :: :: :: :: :: :: what carbs are you running? your bike is a fukin gas hog! you shouldnt be out of gas going that short of a distance! get your self an ims tank if thats the case! Edited November 29, 2006 by Bansh-eman Quote
Polish Posted November 29, 2006 Report Posted November 29, 2006 My bike beat a 421 cub.......mater of fact I left it behind 3 different times........and mine is a 400.........I have to admit it is rider experience and my motor was just built well!!!...........to bad I dont know how to find the guy that built my motor :: Quote
BigRed350x Posted November 29, 2006 Report Posted November 29, 2006 My cub was a lot of fun to dune on. Once you get used to the way the power hits and know how to use that to your advantage its a blast. When that four stroke buddy of yours comes creeping up on you, just grab another gear and slip the clutch a little. Quote
RNBRAD Posted November 29, 2006 Report Posted November 29, 2006 Go the 421 cub. If it's too much power for you then turn in the throttle restrictor screw a few times. Quote
dajogejr Posted November 30, 2006 Report Posted November 30, 2006 a 421 cub on gas isnt going to make 100hp wothout a fat port job... just runnin a cleanup port on a cub isnt going to get you there... Sorry..G. They will if it's put together and tuned right.... 100HP is very possible on gas with just a clean up port. I bet mine on gas was either at 100 or with a few ponies of it. Granted...I run a average compression and a boat load of timing...it's doable. I'm hoping to be 105 to 110 with alky... Once my build is done, you can count on a few hours of dyno time tuning in my Dyna, the meth, etc. The real sad part is...a 7 mil motor will net roughly another 10 HP, and a 10mil another 10 to 12 on top of that. Once you go past 4 mil, you're spending cabbage to jump to 7 or 10, and...since the price is the same, you'd be a fool not to go 10 unless you steal a 7. Quote
HotCarl Posted November 30, 2006 Author Report Posted November 30, 2006 I'm thinking most likely I'm going to get the 392 block because I don't want to have to buy another crank, sence I already have a hotrod crank in there. so...Where is the best place to get the cub and the pistons? Quote
dajogejr Posted November 30, 2006 Report Posted November 30, 2006 Jeff @ FAST gets my vote, but call around. K&T, Redline, Patriot...they all have pretty good prices. Everyone is going to add their two cents on who to buy it from, do a search...make some calls! Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.