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Discussion Starter #1
I know the compression ratio will go up .3 to .5


Can I put a +3mm stroker crank in with any piston?


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I know the compression ratio will go up .3 to .5


Can I put a +3mm stroker crank in with any piston?


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Yes...! Stock or after market piston can be used...

It's recommended to use OEM bearings & gaskets due to tested reliability...!!

HotRod stroker crankshaft, main bearing/seals and complete gasket set for complete installation. +3mm stroke. Makes 471cc. >>>Uses stock piston. Bolt in and go!<<<
 

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Discussion Starter #3
I ordered the hot rods +3 stroker and 500cc big bore kit from CP Carrillo BP Racing and Athena.
13.1:1 compression before the stroker so around 13.5:1 ratio with the stroker. Though I have my doubts, Carrillo insures me that I can use pump gas. I dont mind making a mixture of 93 and a higher octane gas, but I will not run strait race fuel. I raced for years and i already know that i cant afford that. I'll sell the bike if that's how it goes.

Are you suggesting that i still need to buy stock bearings and gaskets?

Here is the kit I bought.

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/283332395724


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I ordered the hot rods +3 stroker and 500cc big bore kit from CP Carrillo BP Racing and Athena.
13.1:1 compression before the stroker so around 13.5:1 ratio with the stroker. Though I have my doubts, Carrillo insures me that I can use pump gas. I dont mind making a mixture of 93 and a higher octane gas, but I will not run strait race fuel. I raced for years and i already know that i cant afford that. I'll sell the bike if that's how it goes.

Are you suggesting that i still need to buy stock bearings and gaskets?

Here is the kit I bought.

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/283332395724


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Yea! (without the +3 stroker).. The "100mm" Athena kit with 13:1 piston you can remain on pump gas of 93 octane due to increased displacement actually drops the compression 0.2~ 0.3. (like 12.8:1)...

But..!! Your kit is 98mm & with a (+3 stroker)..So plan on 96~100+ octane mixture for 13.4:1 compression ratio to be safe...

Listen for any knocking & pinging when you're up & running...If you do raise the octane before you pre-ignition or detonation occurs...(grenade the engine literally)....!!!
 

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Discussion Starter #5
Damn... I was on the phone with athena, and a big distributor and they couldnt get me the 100mm kit alone for like 2 months. I tried and tried to get one and then I came across this kit and thought I may be able to run pump with it. I'm not up to date with it but about 6yrs ago methocyclopentandienal manganese tricarbonal was the best octane booster.
What do you recommend for the times that I dont have race gas and have to up the octane with a booster?

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Discussion Starter #6
Or do u think its smarter for me to return this and try to find the 2 kits separately?

Have u riden a kfx with a big bore? I was hoping it would make a noticable difference. I'm still going to send my head to be ported, and flattened. So maybe all together it will make a nice advancement.

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Or do u think its smarter for me to return this and try to find the 2 kits separately?

Have u riden a kfx with a big bore? I was hoping it would make a noticable difference. I'm still going to send my head to be ported, and flattened. So maybe all together it will make a nice advancement.

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Not a KFX but other bikes with a big bore...Yes..very noticeable difference can be felt...!!!

You can sell the 98mm CP 13:1 that comes with the kit & buy a 98mm 12:1 piston with the +3 stroker to run on pump gas...
 

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Discussion Starter #9
Thanks man....
I just called the company thats mailing the kit and had them switch the 13.1 to a 12.8 piston. I feel good about that.

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Thanks man....
I just called the company thats mailing the kit and had them switch the 13.1 to a 12.8 piston. I feel good about that.

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Shaving your head due to warping will add compression too..how much is determined by how much they shave off...!!!

And remember a +3 stroker crank will increase your compression 0.3~0.5 to a 12.8:1 which will put you at 13:1 or more...94+ octane recommended...so you might need an octane booster..
 

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Discussion Starter #11
I need to find a left side crankcase... I've looked alot and cant find a used one.

Any ideas?

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I need to find a left side crankcase... I've looked alot and cant find a used one.

Any ideas?

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There sold in pairs so it will be very difficult to find just one left side ...reason many left sides are destroyed/
cracked due to the chain breaking without a poly case saver...!!

That's why there are many rt sides for sale & no lefts side available for there bought quickly on Ebay...5 rights sides on Ebay no left sides...

The cheapest I found is new $449.00 https://www.ebay.com/itm/Kawasaki-Replacement-Crank-Case-KFX450-2008-2014-OEM-14001-0573/183830860956?hash=item2acd2c549c:g:-zEAAOSwn-Zc8EW1

Used $400.00 https://www.ebay.com/itm/139-KAWASAKI-KFX-450-CRANK-CASES-RIGHT-LEFT/223554051998?hash=item340cdc1f9e:g:MsIAAOSwAetc~a7Q
 

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Discussion Starter #13
I'm just getting new ones... I know from building turbo cars that if you dont do it right the first time, you will be doing it again.

Do you know what else I should change out for new that doesnt come with this kit while I have the bottom end apart?

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Discussion Starter #14
And what tool do I need to hold the clutch basket?

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And what tool do I need to hold the clutch basket?

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To remove the basket you'll need this... https://www.ebay.com/itm/EBC-CT006-Clutch-Removal-Tool-for-Kawasaki-KFX450R-08-14/192882621838?epid=171130324&hash=item2ce8b33d8e:g:o~IAAOSwbbdbDsDI

to pull the rotor/stator you'll need this https://www.ebay.com/itm/Motion-Pro-Flywheel-Rotor-Puller-Honda-TRX450-R-ER-06-09-Kawasaki-KFX450-08-14/261842101859?epid=1464977089&hash=item3cf7016663:g:sK8AAOSwymxVJF-f:sc:USPSFirstClass!86404!US!-1

If you need an service manual just private message me an email address & I'll send one to you PDF file size 10mb...!
 

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Discussion Starter #16
I will have to buy a larger injector wont i?

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Discussion Starter #18
What kind of seal is used on the oil drain bolts?
The previous builders had both stripped and I'm swapping everything over....
I have both copper washers and rubber prints. I'm going to order an oil plug cuz the one they had isnt right.

I laughed like hell when I saw the oil filters, check this out! And I swear I pulled them just like this!


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What kind of seal is used on the oil drain bolts?
The previous builders had both stripped and I'm swapping everything over....
I have both copper washers and rubber prints. I'm going to order an oil plug cuz the one they had isnt right.

I laughed like hell when I saw the oil filters, check this out! And I swear I pulled them just like this!


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With screens like that I'm surprised the motor didn't seize up or grenade/blow up...!!

Others use rubber or paper washers on there's oil plugs...I use a dab of grey silicon on /mine to seal it..don't want to risk stripping the threads
 

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Discussion Starter #20
I have everything swapped into the new cases except the 2 fat solid dowels that line the two case halves up. I cant get them to budge! Any ideas?

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