Forcefed Posted July 6, 2010 Report Share Posted July 6, 2010 Got a friend wanting to put together a play bike. A wide powerband is what is desired. What would be a wise choice of exhaust for a 421 as cast port timing cub ? Bike has v-3's - 35's & a set of Fatty's on it now. Quote Link to comment Share on other sites More sharing options...
ree_ree Posted July 6, 2010 Report Share Posted July 6, 2010 cpi inframes are fucking outstanding pipes for that motor ! i had almost the same set up only with 39mm carbs. it ran like a raped ape ! Quote Link to comment Share on other sites More sharing options...
pr0blumz Posted July 6, 2010 Report Share Posted July 6, 2010 I agree, go with the CPIs! Best all-around pipe for a cub. Quote Link to comment Share on other sites More sharing options...
stclark816 Posted July 6, 2010 Report Share Posted July 6, 2010 I agree, go with the CPIs! Best all-around pipe for a cub. Disagree!! I had Rockets on my 421 Cub with 35mm PWK's. It flat out SCREAMED! Rockets worked the best on my motor, and anyone that ever saw me run or raced with me knew it screamed. CPI is a great pipe no doubt, but to say it's the best all around pipe for a 421 cub is debatable!! Quote Link to comment Share on other sites More sharing options...
okbeast Posted July 6, 2010 Report Share Posted July 6, 2010 (edited) Disagree!! I had Rockets on my 421 Cub with 35mm PWK's. It flat out SCREAMED! Rockets worked the best on my motor, and anyone that ever saw me run or raced with me knew it screamed. CPI is a great pipe no doubt, but to say it's the best all around pipe for a 421 cub is debatable!! Shearers scream too Edited July 6, 2010 by okbeast Quote Link to comment Share on other sites More sharing options...
camatv Posted July 6, 2010 Report Share Posted July 6, 2010 all around bike? dont use a cub! Quote Link to comment Share on other sites More sharing options...
pr0blumz Posted July 6, 2010 Report Share Posted July 6, 2010 Only my opinion.... Quote Link to comment Share on other sites More sharing options...
dajogejr Posted July 6, 2010 Report Share Posted July 6, 2010 Got a friend wanting to put together a play bike. A wide powerband is what is desired. What would be a wise choice of exhaust for a 421 as cast port timing cub ? Bike has v-3's - 35's & a set of Fatty's on it now. Professor... Now is a good time yet bad time to answer that. Before now, my answer would be simple...throw some CPIs and be done. The original creator of the Rockets has a pipe called the R2 which is better in every way than the Original Rockets. Jim @ Passion in conjunction with Sniper Pipes are making inframe pipes as well. While CPIs, In my opinion are the old, proven pipe...it's always worth a look at something new. You're not looking for peak HP...as of right now (R2 and Sniper pipes still in infancy/testing at this point) so Shearer would be the obvious choice there. R2 and Sniper are both site sponsors...give each a call/PM or Email and see what they say Chris. I'll vouch for you 100% old friend... Good luck, let us know what you end up with. Quote Link to comment Share on other sites More sharing options...
sheefreak Posted July 6, 2010 Report Share Posted July 6, 2010 Lol....is this an experiment Chris? I know you have been playin w/the 4 strokes lately but seriously???? Quote Link to comment Share on other sites More sharing options...
Forcefed Posted July 6, 2010 Author Report Share Posted July 6, 2010 Professor... Now is a good time yet bad time to answer that. Before now, my answer would be simple...throw some CPIs and be done. The original creator of the Rockets has a pipe called the R2 which is better in every way than the Original Rockets. Jim @ Passion in conjunction with Sniper Pipes are making inframe pipes as well. While CPIs, In my opinion are the old, proven pipe...it's always worth a look at something new. You're not looking for peak HP...as of right now (R2 and Sniper pipes still in infancy/testing at this point) so Shearer would be the obvious choice there. R2 and Sniper are both site sponsors...give each a call/PM or Email and see what they say Chris. I'll vouch for you 100% old friend... Good luck, let us know what you end up with. Thank you for the kind words. And thank you all for the replies. Experiment - lol - nah ... the 4 stroke stuff is fun, but we are still giving the oem cyl 4 mil a hard way to go at the track. Last outing was a 3.77 hosed. About this post - there is a kid up the road that wants me to make his bike faster, he reminds me of myself back in the day - Knows nothing about Banshee's & wants to be the fastest guy out there in the field, but doesnt want to give up any powerband - he can't comprehend why that is so hard to do - lol ... With the cub casted at 197/130 - I agree ... not quite the all around play bike - maybe a new casting is needed With this cat being young & highly impatient, he wants this done yesterday & is convinced all Ebay ads are in his best interest (again, we've probably all been there at one point) I advised him if he wanted a big boost in power, bolt up a cub & buy a 4-stroke for bottom end. That being said I (as you mentioned) thought I'd just bolt up some CPI's & be done. But I started searching good old HQ for the latest in the inframe world & noticed that there are a few more options nowadays ... at least in the near future anyway. So, if I can cool this guy's heels for a tad, it sounds like he may be better off ... I holler at the site sponsors & see what the skinny is ... A little more on what he is riding now & why he is trying to get it done right this time ... OEM cyl - 4 mill - V3's - 35PWK's - 24cc domes at .070 squish - the ports are at 198/135 & Fattys - lol - ...shaking head... Quote Link to comment Share on other sites More sharing options...
sheefreak Posted July 7, 2010 Report Share Posted July 7, 2010 I have read about the great times you have been running w/that motor. Congrats, that is a great number for that setup!! I am sure you guys will go faster yet. Good luck w/the pipes. There seems to be quite a few options these days Quote Link to comment Share on other sites More sharing options...
camatv Posted July 12, 2010 Report Share Posted July 12, 2010 lots of options and lots of opinions.. 70 tho squish!!! does he run it flat out down a hill in 6th with pump gas 87 octaine witha stiff wind behind him!!.. HA drop that cylinder down and get some of that tune back for him.! you get that motor to run right and even with just the fmf's it'll probably make him have to go change his whity tighty's.. i have a friend around here like that but he loves 3 wheelers well he had a trx with a 330esr in it really bad tune but wanted 3 wheels i told him thats a lil much for a trike on stock arm welp, cr ignition and some tuning work and there it was,, he fliped right off the back of it the first time it grabed in sand with dirt tires ripped the rear fenders right off i laughed so hard. that trike was a lot of fun later he said yea maybe its a lil bit too much!! you got to learn to walk before you launch to the moon!! Quote Link to comment Share on other sites More sharing options...
Forcefed Posted September 18, 2010 Author Report Share Posted September 18, 2010 ... figured the serval was in this guys best interest ... so here we go. Quote Link to comment Share on other sites More sharing options...
252wheelieking Posted April 24, 2012 Report Share Posted April 24, 2012 what ever happen with the guys build? Quote Link to comment Share on other sites More sharing options...
ClayAiken Posted April 24, 2012 Report Share Posted April 24, 2012 He hasnt signed in since 11/29/11 Quote Link to comment Share on other sites More sharing options...
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