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Looks awesome. Keep us posted. What will the bore and stroke be?
 

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Discussion Starter · #4 ·
it is a 76mm stroke, 85 bore. this cyl is ready to go, it has been ported and on its way back from plating. should produce some nice #s
 

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For one, you can't bore a Pro-X cylinder out to 85mm. I think the max is like 79-80 or something. The CPI website says that the port layout is a lot better. The tall studs in back allow them to enlarge the intake transfers.
 

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It also uses a larger CR500 intake and reeds.
 

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Discussion Starter · #11 ·
There are a ton of advantages with this set up. This is actully set up to use a long rod 4mm crank. very common crank, which will keep the price of the build down. BUT........ we are testing this set up to see if it shakes to bad....may need a heavier crank like we use in the sabers....and we may end up using the 137mm rod in the end. the 4mm 130.3 set up is designed to use the polaris 85mm piston, which is an off the shelf piston. the 137 rod will require a special piston which will be done in a few weeks. This cylinder uses a tripple transfer port design, triple port exhaust etc etc. What really will make this engine shine is that in fact it does use a CR500 reed cage, which is the weakness in the pro x cyl. The pro x cyl only is able to go to 80.5mm is the biggest, and when you get out to about 79--79.5 i have seen multiple problems with them blowing the o rings out, depending on set up. The sleeve just gets too thin. This cyl requires a TON of case work to get it to fit. CP has the sphinx cyl, which is a direct replacement to the Pro x....all your std 250r componets will work. The very first cyl, which had a bad head design which has been fixed, leaking water in the cyl, and a hurt motor made 67hp on the dyno with a TRX5 pipe. I would say its prolly a low 70 hp motor on gas?????????? We are anticpating mid to high 80's with the Puma. Oh, i forgot too , on the puma your STD 250R pipe will not fit on the flange as the flange is larger, uses the same as a Saber. We have not tested anything yet, but my guess is that any off the shelf 250R pipe was never designed to run with a motor of this size....we will see. We will be testing our new CR programable ignition as well, since DYNA no longer makes one for the CR.. ITS REALLY COOL!!! LOL We will first start our testing with a 44mm lectron bored to a 46, but i think we will end up with something a bit larger...again we will see. I hope i covered most of your questions! LOL if not speak up! the web site is CPINDUSTRIES.COM
 

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Do you know any more details on the sphinx that makes 65-70 hp. Is that with drag porting? What displacement, and other components were used?
 

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Discussion Starter · #14 ·
i do belive it was more of a dune port. it was 363cc, trx5 pipe was used, cr ignition, v force reeds, and i "think" it had a 41.3 lectron.......the pic i posted here is a pic of i set up on alky, but made 67 on gas.......there is a video of it running, ill have to try to find it.
 

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There could be another option if you havent already thought of it. The ktm 250 132 rod.The bore of the big and small ends of the rod are the same size as the honda 130.3. I like the look of this rod better because its beefier.
 

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the 137.5 mm rod will be a much better option than the KTM rod. Alot stronger and will provide a better rod/stroke ratio than the shorter options, especially on stroked cranks. I am waiting for some of the results on these motors before building one. I will balance the crank on mine for sure and even after this, the crank will be much cheaper than the sabertooth crank. I will be interested in the HP but I would assume a 4 mil stroker on gas with a tame state of tune should make mid 70's HP and tons of torque. I and am assuming this with a current 250r style pipe with a larger end stinger applied to it and a standard CR250 ignition. The perfect all around dune motor.
 

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Discussion Starter · #20 ·
the 137.5 mm rod will be a much better option than the KTM rod. Alot stronger and will provide a better rod/stroke ratio than the shorter options, especially on stroked cranks. I am waiting for some of the results on these motors before building one. I will balance the crank on mine for sure and even after this, the crank will be much cheaper than the sabertooth crank. I will be interested in the HP but I would assume a 4 mil stroker on gas with a tame state of tune should make mid 70's HP and tons of torque. I and am assuming this with a current 250r style pipe with a larger end stinger applied to it and a standard CR250 ignition. The perfect all around dune motor.
The 137 will prolly be the rod to use, as far as a Puma crank being cheaper then a saber crank, i highly doubt it........i do think it will need to be balanced though, i expect it to shake..... i would think a Puma on gas will make 70's, but using a non programable ignition and a std 250r pipe may be a stretch????? we will know very soon though! :)
 
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