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DRZ400 470 FCR41 jetting?

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building my motor now. looking for the jetting i would need for the FCR41

434cc Big Bore, single base gasket

+4mm stroker

Ported Head +1mm Valves

Yoshimura Cams

K&N Filter

Sea Level

EMR or EMN Needle?

thanks

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where did the carb come from?

make sure you add several base gaskets if you are gonna use those cams or you will have constant head gasket issues.

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i am in the process of buying the carb now from a member, he said it was froma ktm and jetting it has now is from your recommendations but he only had a big bore

thanks for that tip eddie. what do you recommend. i copper coat my racecar headgaskets and noticed it is recommended on these headgaskets also, so that i will definitely do. what is it with these cams that causes problems? i plan on running the RHC's next year when i have more money, i am dropping more than i wanted to right now but whatever. i will have my stock motor as a spare.

edit: from our pm's

from a 05 ktm 450

No TPS, removable KTM bell, The cable mount is part of the body. It was jetted for my 439. It has the EMR needle (recommended by Eddie) and 175 main. Will come with the correct boots and pull cable. I think I have an EMN needle and 172 main too

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the yosh cams do not have enough duration for the motor to run correctly or bleed off cylinder pressure. in order for it to not push head gaskets you will need lower the compression drastically and it still wont run correctly.

if the carb has my jetting setting you should be able to bolt it on and go.

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so i need to use the full 3 layer gasket? how is it going to run? finally are the RHC cams the only cams capable of doing this? is there a measurement for the valve springs to determine if they can handle the RHC cams?

thanks again

EDIT:

i got some pics of the carb today... can this carb be confirmed as the right style for this application?

IMG_1999.jpg

IMG_2000.jpg

IMG_2001.jpg

IMG_2002.jpg

Edited by Turbophein

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no more like 2 three layer gaskets.

that carb will work with the rest of the conversion parts.

i need to know the seat pressure,over the nose pressure and max lift before coil bind for the springs.

my cams were specifically desinged for stroker motors.

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no more like 2 three layer gaskets.

that carb will work with the rest of the conversion parts.

i need to know the seat pressure,over the nose pressure and max lift before coil bind for the springs.

my cams were specifically desinged for stroker motors.

Based on this, at .356 lift, the spring assembly makes 171 lbs. It stacks solid at .442".

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yes,it will work but you will be basically durability testing them as they have never been tested.

what i sell i know is durable.

thanks eddie i really appreciate your reply's. we will see how everything goes... wish i knew someone who wanted some yoshimura cams, so i can buy the 187's.

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