Sneaky 401cc stroker- the easy way and more.

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So the dyno results are in, The 405 stroker made 30.7 Hp and 27 Ft Lbs. to the tire. I have 25" GBC dirt Devil AT's. Peak power was at 6,500 rpm and peak torque was at 5,000 rpm, however the real tail is that this motor held over 25HP to the tire to over 9,000 rpm, was still making 23hp to the tire at 10,000 rpm, and finally the carb gave out at around 11,000 rpm as the motor started to lean out towards 14-1 AFR's, and started mis-firing. It pulled over 54 mph in 4th gear, this motor has the full big bear trans swap and the 02-06 big bear front diff swap so I have electronic 2x4/4x4 modes, which means its capable of 65+ in 5th.

Which after trail riding it the deeper 1st gear is very welcome for tight technical terrain, it makes the rough terrain easier to deal with, and with the extend RPM's it still pulls faster the the stock trans by 2 or 3 mph in the same gear. It has so much power its honestly like riding a 450 sport quad, in 3rd out on the trails just mildly rolling into it blows the hides off and full corner power slides are epic and easy, 4th pulls way harder than it used too, and beats 5th for outright speed, lol. 5th gear is so long but still pulls hard, and honestly cruising at 30-45 mph the motor is so much happier with the lower rpm.

The dyno graph images may not load today as Photobuckets is down so check back to see!!!
 
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This photo shows the entire pull, the numbers are a little lower, but this is on a smoothing setting of #5 which is very stingy, think mustang chassis dyno, the top photo is on setting #4 the standard setting for our chassis dyno. Going down to a setting of #1 is equivalent to a Dynojets numbers. Every Setting was above 30HP except for the 5th, which even there still got 29.9 so its legit kids!
 
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So I will do a list of every mod done to this bike

1) Manual Clutch conversion shaves over 6lbs of rotating mass from crank

2) Big Bear 400 parts: Crankshaft, Rod and Counter weight, Jug, Front timing Chain guide, Cylinder Head Bolts, Big bear Transmission with the wolverines Intermediate Gear swapped onto the Counter shaft end, and a 02-06 Big bear front diff with the big bear inner CV cups swapped onto the wolverine axles, Kodiak/Big Bear/Grizzly Throttle lever/housing, and wires/plug to front diff actuator.

3) JE piston 85mm shelf piston for 350 warrior/wolvy, cut the valve reliefs radially to clear valves.

4) Web Cam custom grind, 477 lobes = 4 degrees more duration than their .390" trail cam, and gross lift comes in at .427". So not a race cam for sure, but a mega hardcore port job on head definitely a must with any cam over .390" lift. I did the port work myself, besides having my own dyno, I also have my own flow bench.

5) KMPI S/S valves and titanium retainer kit.

6) Megacycle vernier Cam gear.

7) DID 92 link Cam chain full roller

8) Barnett Dirt Digger clutch kit

9) Mikuni BTM 36mm pumper carb from a warrior and the intake too, as well as CFM fabbed air box, K&N filter, Irony here is I am running a #60 PJ and a #130MJ, that's 5 sizes smaller than stock because well the carb is undersized for the motor, with the stock jet my AFR's were like 10 to 1 and it ran like crap, mikuni's lol. I may step up to a FCR 39mm or a TM 40mm pumper, to see if I can nab more hp yet still, but I don't want an on off switch either.

9) Factory Head pipe, and an FMF slip on

10) DWT Redline rims - shaved 12 lbs, lithium ion battery - shaved 8 lbs, Front Rack delete - 10lbs. Going to Fab a custom rear from aluminum too!

11) Richochet Skids- full set + 10 lbs. after deleting stockers.

12) Elka legacy series shocks full set, seriously best mod for long distance riding hands down.
 
This was a 350 warrior with a ported head and 10-1 piston in it, no cam, no pipe, no air box mods, no other trickery, on a pretty stingy dyno lol. Also it had 22" BKT's with stock gearing, so not the lightest or the best for not sucking up power.


Ok here was the missing image from warrior dyno for those who were curious
 
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