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DRZ 400sm newbie question on the jet kits

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My dad just bought a 2016 400sm and I’m trying to get him in the right direction with mods. I’ve tried researching both jet kits but still have questions. What’s the difference between the dyno jet kit and the JD jet kit? Also, how do you know which jets to use for that kit?  Does one of them include the remote air/fuel screw? We are looking at doing the full yosh rs2 and the 3x3 mod. 

 

Thank you for the help. 

Edited by teamz492

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My dad just bought a 2016 400sm and I’m trying to get him in the right direction with mods. I’ve tried researching both jet kits but still have questions. What’s the difference between the dyno jet kit and the JD jet kit? Does one of them include the remote air/fuel screw? We are looking at doing the full yosh rs2 and the 3x3 mod. 
 
Thank you for the help. 
JD includes 2 needles and genuine Mikuni mains and a pilot jet.

Dynojet includes 1 needle, a replacement spring, drill bit and screw to remove the brass plug and a drill bit to modify the slide bleed valve. The jets are a proprietary size that don't equate to Mikuni sizes though. They also used to , possible still do, include a coupon for a free Dyno run at a Dynojet equipped shop. Make sure you get the kit for the SM, it includes both stage 1 and 2 jets.

I don't think you will go wrong with either. Both include very detailed instructions. I started with the Dynojet Kit, 3x3 and WB slip-on and it worked very well. The JD has a larger following though.
Neither include a fuel screw.

If he haven't bought the Yoshimura yet don't. Buy the MRD instead. Besides the superior performance it is hand made in the United States by a man named Dave.
All the threads with people complaining about the noise were written by people not familiar with 4 stroke MX bikes. To say that the Yoshimura itself is quiet is ridiculous, they are both loud. However, a stock KX or YZ250F at full tilt are louder than either the Yosh or MRD.

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44 minutes ago, ohiodrz400sm said:

JD includes 2 needles and genuine Mikuni mains and a pilot jet.

 

Genuine most of the time as we have found out here before. 

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Thanks Ohio for the reply. How we will know which jets to use? Does the kit some with an jetting diagram or spec? 

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Thanks Ohio for the reply. How we will know which jets to use? Does the kit some with an jetting diagram or spec? 
The JD kit tells you what to use based on mods , temp and elevation. The Dyno Jet if I remember correctly only covers stock or 3x3 and exhaust.

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https://docs.google.com/spreadsheets/d/1HNSB3DrqJqHTInjVDKKS4HNSHZPbdK0ElbfNI5HxuZg/edit?hl=en#gid=1172546203

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On 10/28/2018 at 4:16 PM, ohiodrz400sm said:

If he haven't bought the Yoshimura yet don't. Buy the MRD instead. Besides the superior performance it is hand made in the United States by a man named Dave.
All the threads with people complaining about the noise were written by people not familiar with 4 stroke MX bikes.

If you're not going to change the carb and the cams, the only noticed difference will be the sound. Yoshimura is made in the USA too, with technology they develop. Not knocking the MRD, but it's a stolen Yoshimura design.

FMF makes pipes for the DRZ too; right here in the USA!

http://www.yoshimura-rd.com/

https://www.fmfracing.com/

 

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If you're not going to change the carb and the cams, the only noticed difference will be the sound. Yoshimura is made in the USA too, with technology they develop. Not knocking the MRD, but it's a stolen Yoshimura design.



FMF makes pipes for the DRZ too; right here in the USA!



http://www.yoshimura-rd.com/



https://www.fmfracing.com/



 
I disagree about a pipe not helping without an FCR or cams.

Yoshimura abandoned the design. MRD picked up the ball and ran with it. People should be greatful someone cared enough about the DRZ to do that. Even if it was probably mostly fast Eddie's looking to make a buck. Either way a great extinct exhaust system was cloned and lives on today.

They're other USA DRZ pipe makers also. None of them offer a 1 time free crash repair like MRD does as far as I'm aware. None of them support mid to top end power, especially on modified engines. Unless sound is truly a concern it seems silly to buy an aftermarket parts that will limit further performance modifications. Having owned 3 different aftermarket exhausts I cannot in good conscience recommend anything but an MRD ZPro to anyone with performance as the #1 priority.

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The dynojet kit doesnt have a pilot jet and as stated has different jets and needles . You do get an easy out to remove the brass mixture screw plug though . The james dean kit has needles , main jets , pilot jet and float bowl screws . These screws are allen heads as the std ones are a japanese sizing and made of butter . I agree with ohio , a pipe will make a difference as the std one is a smaller diameter  and getting an aftermarket or standard E header will allow the exhaust to breath better . If you put on an FCR and cams , or even go the big bore , you will need a pipe to compliment it , greg

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