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Noob needs help with FCR MX41 mod

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Hi Guys, I know this has probably been gone over before and Ive seen a guy on Youtube with this exact mod and tried to contact him with no luck.  so sorry If im repeating an old thread.


ive got a 1993 XR60L with snorkel removed, White Bros slipon, and Uni filter. Shes been put up for about 4 years (I know..) and now I'm getting her back going. Carb was gummed up and I decided to upgrade while it was out. I bought a FCRMX 41 without TPS, but with hot start and choke that came off a KTM 520SX from like 2000. The damn thing measures almost perfect to the original, I was very surprised.. 

Well its got like a 180 main I havent opened to see the others, but I want to rejet for 700 to 1200 altitude. The dude with the black/red on youtube (BugCrush3R) named out the jets he used and the needle etc. I guess I just pull out the old and in with the new.. I see there ar air boot flanges, but mine is only 1mm shorter than stock.. do I need the adapter boot... also, Ive got a big ass hose coming to the air inlet side of the carb from what I guess was smog or blow by return.. do I just block this thing off ?? plus a bunch of other thin hoses hanging down.. I suspect overflow hoses that I just leave disconnected ?


Now I get confused.. theres adjustable leak jets and special float bowls and Tokyo Mods stuff for this carb.. which of that stuff is most handy for tuning on the fly, and which is overpriced BS ?? 



I just wanna ride, and I'm not a MX'er... trail dude that goes single track in the woods here and there..


Any help or feedback would be greatly appreciated


Thanks !



Edited by Verastarr

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Please read this thread for all your answers as to what jets to use , AP questions its all in the first 5 or 6 pages.  Its a great read


To get you started you need,



From my youtube channel (btw I'm that guy on youtube),




My current jetting as of 2013-03-14 and results are as posted below. NCVT needle was found to be the best needle. I have since upgraded to a full FMF exhaust system consisting of a set of powerbomb headers and a FMF Q4 exhaust.

0'-1000' elevation ambient temp. 10c
MJ158 (use 155 if over 20c)
PJ42 1-3/4 turns out
NCVT needle 2rd clip from top
R&D leak jet just cracked open 1/4 turn to give 1 sec squirt duration

0 - 13.4
1/16 to 1/8- 13.3
1/8 to 3/8- 13.2
3/8 to 3/4- 13.0
WOT - 12.6
Edited by D0T-C0M

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