high compression vs. stroker?


46 replies to this topic
  • Justin89

Posted October 21, 2008 - 12:56 PM

#41

I cant believe people need NOS on these bikes :lol:

  • yz480doinwork

Posted October 21, 2008 - 03:54 PM

#42

any one that rides in the sand dunes knows you always need more power

  • IDAHOBALLER

Posted October 22, 2008 - 07:42 PM

#43

any one that rides in the sand dunes knows you always need more power


I AGREE 100% as a dune rider myself. When it comes to the dunes HP is an ADDICTION that can only be dealt with by adding MORE POWER!!!:p

This is the reason why I am building a CR500af with a fully drag ported/nitroused bigbore/stroker engine for use as my sand only ride. I sure hope the 85+hp on motor and 100+ on spray will keep me happy in the sand for a while....:lol:

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  • yz480doinwork

Posted October 22, 2008 - 08:23 PM

#44

dam it sure should! i would need a 20 horse shot of nos to run with that. maby less if i get it stroked and cams. but boondocker says you can go up to a 30 hp shot...weather it will hold together is a whole nother story. so is how much i weigh!

  • IDAHOBALLER

Posted October 23, 2008 - 05:45 AM

#45

dam it sure should! i would need a 20 horse shot of nos to run with that. maby less if i get it stroked and cams. but boondocker says you can go up to a 30 hp shot...weather it will hold together is a whole nother story. so is how much i weigh!


I have built quite a few 450 motors for the sand and from my experience with 450's the Yamaha motor seems to be pretty reliable until you get to about 70-75hp and then you have to be carfeul that you do not end up bending a rod. Also at that level you will have to have a lockup clutch. Once you get above the 75hp mark you really have to start worrying about your cases cracking around your main bearings.

If you plan on running NOS on it then I would highly reccommend that you get some kind of programmeble ignition so that you can run a retarted map to prevent detonation, especially if you plan on keeping the compression ratio above stock. I would also HIGHLY reccommend that you do indeed go with the complete Falicon set up just for reliability reasons. I have seen turboed 450 Yamahas making 110hp with a falicon bottom end that held up fine. On my last YFZ450 that I built, I ran nitrous on top of a 14.5:1 stockbore piston and never had a single problem thanks to the ignition and the sonoco 110 race gas that I was running in it.

As for how much can you spray, on a high compresssion motor I would not go much over a 15-20 shot, but if you build a low compression motor (like 10:1) you can spray upwards of 50hp.

Be fully prepared to replace your rings every year as they will wear out very fast when making that much power and being ridden hard in the sand.

  • xorron5

Posted October 23, 2008 - 11:40 AM

#46

I AGREE 100% as a dune rider myself. When it comes to the dunes HP is an ADDICTION that can only be dealt with by adding MORE POWER!!!:p

This is the reason why I am building a CR500af with a fully drag ported/nitroused bigbore/stroker engine for use as my sand only ride. I sure hope the 85+hp on motor and 100+ on spray will keep me happy in the sand for a while....:lol:


WORD MY BROTHER, i found out the same thing if you want the ultimate ride
u better get the ultimate machine before start hopping up !:lol:

  • yz480doinwork

Posted October 23, 2008 - 06:38 PM

#47

awesome info guys thanks!





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