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stroked crank?

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what does it all require?

do I just buy a stroked crank and a rod and install it? im not going to have to mess with any timing or clearances like piston/valve clearance?

when/if my crank ever decided to go (only thing on my bike I havnt replaced yet... sure hope its not this summer!!) I am probably going to throw a stroked hotrod crank+rod into it, unless someone here has a better suggestion.

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You MAY need a piston that has been machined to accomodate the longer stroke...I ran into this when building a 342 stroker motor for my Mustang. Not completely sure about a bike though, looks like all the kits out there just include the crank and rod so they may have taken the extra length out of the rod. I would definetly go with a good aftermarket piston and talk to an engine builder or company that specializes in this type of mod...Ron Hamp, Big Bore Thumpers etc.

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Stay stock on your crank. JMO. It causes more engine vibration than you will like. Your best bang for the buck on power is to get head work. If you wanted to up it just a little bit more, you could slap a high comp piston in it at the same time. Of course that all needs a good exhaust system to be worth anything. :banana:

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Stay stock on your crank. JMO. It causes more engine vibration than you will like. Your best bang for the buck on power is to get head work. If you wanted to up it just a little bit more, you could slap a high comp piston in it at the same time. Of course that all needs a good exhaust system to be worth anything. :banana:

+1....but my buddies YZF450 quad, which has been bored, stroked, cam-ed, etc is one BAD machine in the dunes.

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well I figured when the crank does go, which I imagine is the next thing to go.. why slap a normal one in there when I can put a stroked one instead? engine vibration isint a concern for me, and I dont race so the "too much power" theory does exist with me :banana:

I would also probably throw a big bore/high comp piston on it also. mine is already stage 2 cam, exhaust, JD jet kit, stock piston. SS valves with the 08 head + exhaust valves which are smaller than the 05 which takes away from my top even more combined with the SS intakes valves which is fine.

I have a friend who has a yz450f bike thats bored 2mm and stroked 3mm, I believe its something like 510+ cc now. I havnt ridden it but imagine its pretty bad ass, he doesnt seem to have any problems with the extra power where we ride at. only complaint is the tires he goes through.. basically I just want a ridiculously powerful bike, unless it takes away from my reliability, then its not worth it. ive ridden my 450 for quite a while now and have gotten way used to the power, its lots, its plenty, but I always want more and more and more.. basically a 60 or 65 HP 450 and ill be happy for a few summers until I want more!

will a stroked/bored engine last significantly less than a normal engine? if I have to rebuild it every 50-100 hours forget about it! the stock engines last 200+ hours IMO.

just want to make sure im prepared and have my $hit together for when the time does come that the crank needs to be replaced, which is hopefully not soon!

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will a stroked/bored engine last significantly less than a normal engine? if I have to rebuild it every 50-100 hours forget about it! the stock engines last 200+ hours IMO.

I was hoping for 200+ hours! My 100% stock motor's crank went at 98.0 hours. I think it's kind of a crap shoot, but those mods certainly wouldn't make it last longer.

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I was hoping for 200+ hours! My 100% stock motor's crank went at 98.0 hours. I think it's kind of a crap shoot, but those mods certainly wouldn't make it last longer.

ouch. I seen your pictures. my bike has gotten louder lately, but I keep telling myself its just the SS valves that I installed and not the crank :banana:

mine currently has 120 hours put on it by me, and the first owner put on 10-30 id imagine. I just sure hope she doesnt decide to go this summer... I will be very mad if it does!

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My friend who is similar speed to me bought an '07 in '07 (I bought mine in '09). Never touched the motor, just did valves and piston this winter at an estimated 130 hours; although I'd estimate closer to 300 since he rides the same as me times 3 years.

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yeah it seems like some people get awesome bikes, and others get bikes that were either made on a monday or on a friday! :banana:

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