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FCR 39 mx on DRZ400S HELP!

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Okay so I just installed the TT fcr kit on my drz. Installation was pretty smooth.  And today was the first day I was able to take it out for a proper test ride. Starts fine seems to run fine. But there is now a "chirping" sound coming from the carb(?) only when throttle is twisted . If I take the air box cover off it is way louder. No "chirp" at idle. 

I sprayed carb cleaner around the manifold while the engine was running. No change in idle.

I read a post saying it is a common sound for a FCR 39 MX on a drz400 and not to worry. But would like some conformation so I a quit worrying haha!

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25 minutes ago, fourfiftee said:

I got a FCR mx39 on my bike. That chirp noise happens to me too. Think your good 👍

Awesome! Thanks for the reply. 🤙

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21 hours ago, William1 said:

The 'chirp' is from the vacuum release plate.

Thanks for the info! I was getting really curious as well.

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Is there any performance gain going from slant to mx body on the fcr?

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Is there any performance gain going from slant to mx body on the fcr?

I noticed a small difference going from a 18 year old YZ400F slant to a new FCR-MX 39mm. I attribute most of the change to the new carb having better jetting and being brand-new. The difference wasn't significant though.

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Cool good to know. I picked up a 2004 E model that the previous owner put a new mx on and it actually feels a hair better jetted than my 2017SM with mx fcr. They r both jetted same but the SM has a JD needle and the E has whatever comes standard from TT fcr kit.

 

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Cool good to know. I picked up a 2004 E model that the previous owner put a new mx on and it actually feels a hair better jetted than my 2017SM with mx fcr. They r both jetted same but the SM has a JD needle and the E has whatever comes standard from TT fcr kit.

 

Well the E does have higher compression and better cams going for it unless you have changed yours already.

 

Sent from my XT1650 using ThumperTalk mobile app

 

 

 

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