FST Stroker Kit information Q&A

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DeathShadow

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For those of you who may have some questions about Mickey Dunlop’s Stroker kit for the Warrior (www.fourstroketech.net) here are some questions I asked him briefly about recently:

Q: Who makes the piston for this kit and how much "lighter" is it?
A: The 11:1 piston is made by JE for FST and is 2oz lighter THEN STOCK!

Q: What RPM is this stroker kit safe to operate up to under?
A: With valve springs and a cam this kit can run to 9K and makes power between 5K - 9K.

Q: What gearing would be most appropriate with this kit and up to what gear are wheelies EASILY done in?
A: A 16T sprocket should be used and wheelies in 4th gear can be done with ease!

Q: Is a stronger rod needed to run this safely?
A: No the stock rod is strong enough however an oil cooler should be run!

Q: What is the average turn around time for a crank?
A: Most cranks are already made and swapped out. If a crank isn’t in stock for a swap about 2 weeks.

Q: Is all work done on the crank achieved in house?
A: Yes

Q: Does this kit use a spacer?
A: No it does not this and the lighter piston contributes a great deal to reliability!

Q: Are the cranks trued?
A: Yes
 

dswwarrior350

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Thats some good info. I like the part that is doesnt use a spacer, that way it makes it hidden, some people like me and others could look and see if motor was stroked simply by looking at the base of the cylinder. Another thing is they use the stock rod, i guess that means i can run my 12:1 on the stock rod too. I gotta get an oil cooler lol. good luck with that stroker death it should rip. Are you going with the 446 or the 430? 4 gear wheelies with a 16!!!!!!!
 

yamarider

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The head mechanic at the atv shop told me that the fst kits required boring out part of the case because the piston skirt drops down into the case or something like that. Is that true or could he be thinking of something else? I told him that I wanted to get the fst 430 kit in the future and he steered me away from the idea.
 

evilhaze

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he just steered you away cause he's too lazy to throw it on the mill and indicate and set it up,,,let me tell you, setting up engine blocks is a pain in the A$$
 

yamarider

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The shop sends all the parts out that need machined. He told me that it would probably cost over $1800 total cost for the kit and the installation, and that it wouldn't be reliable because the head bolts will break or pull out. I'm going to go to another shop to ask about it before I get any motor work done, but that won't be for at least 5 months.
 

DeathShadow

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Yes the cases need to be machined that is 100% true 1,800 sounds steap! If you need a place to do it I can get my shop to do all the labor for pretty damn cheap (we have a full machine shop as well)! The headbolts breaking is a load of **** FST has been building warriors for 17 years and I have spoken to many people with their stroker of 6 years... What you have to watch with a stroker most importantly is piston speed and the bottom end rod bearing. Your shop probably also doesnt know how this kit is done (most assume a spacer or some other crap like that).
 

yamarider

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what would you consider a reasonable cost for the kit and installation? I was thinking 650 for the kit and maybe another 600 for installation.
 

outkastjoe

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I spent @2 on machine work and am doing all the rest. I split the cases myself and just took the pieces to the yam dealer that i couldn't do i.e flywheel pulling and machine work. The service manager at my shop shop was like wow a stroker. This is gonna be fun. He actually gave me some damn good service. His name is Mike Velasco. He was actually pretty cool to me.
I still haven't finished it yet. Work and stuff getting in the way.
 

DeathShadow

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I spent @2 on machine work and am doing all the rest. I split the cases myself and just took the pieces to the yam dealer that i couldn't do i.e flywheel pulling and machine work.
I still haven't finished it yet. Work and stuff getting in the way.
Is the piston you got with the kit a slipper piston?
 

outkastjoe

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I really don't know. It was all in a box. The piston didn't have any label or anything. Here is a pic I took last night.Right before I put the cylinder on.
 
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