Now for the fancy part. Our engineering group just bought a 3D printer so I made my own custom perfect fit adapter. It is solid plastic. I can't say for sure how well it is going to hold up but initial test are promising. Gasoline/ carb cleaner seem to have no affect on the plastic. It is winter here so I haven't got any real world field testing done. There are several differenet types of plastics that can be printed so I might want to try a few different prototypes. Anyone who wants the file, pm me and I will send it to you. If you know someone who has a 3D printer have them make you the part. We have the "Makerbot 2" it took 6-1/2 hours of printing time to make it solid.
You will need to file off the lip of the carb in order to install the printed adapter. I used RTV sealant to glue it on. It's a snug fit, even without the RTV it's hard to get off the carb.
I used DOT-COM's Jetting suggestions and it runs great. Thanks for all your hard work buddy!
NCVT needle 3rd clip from the top
leak jet is still stock - I think it is something like #65
Here is the total parts list and pricing.
2007 CRF250 FCR MX --- $130 Shipped - Ebay
2007 CRF250 Tusk throttle cables $14 -- Rockymountainatv FYI --- 4" longer than stock XR650L cables but will fit the XR650L housing. The longer cables fit much better. No binding or Stretching when turning.
Hot Start Button OEM parts 2007 RMZ450----Rockymountainatv 13410-35G10 STARTER VALVE | MODEL K5 $18.88
XR650L intake boot -- $23 shipped --- Ebay
Jets Prox brand from -- Rockymountainatv -- $15
NCVT Needle OEM parts 2004 YZ450F --- Rockymountainatv TA-14916-VT-00 NEEDLE (#NCVT) | $9.37
Custom printed part Freebie!!!!
Total Cost $210 give or take a little
If you have any question let me know. I will do my best to answer them. Enjoy the new found power.
A few members who have done this upgrade have reported that the gas tank was interfering with the top of the carburetor. Due to possible variations when buying a used carburetor or if you are using the stock tank or an aftermarket tank, this may be the case. It is very easy to remold or push in the area on the tank that is the problem. Firstly remove the tank from the bike and drain all the gas, leave the cap off and let it air out for a few days. Mark the area that needs clearance. This next step is very important, only use a heat gun to heat the plastic tank, this is the only safe way to gradually bring the plastic up to temp until it is soft enough to deform with some applied force (palm of your hand). Do this slowly moving the heat gun in small circles to gradually bring the area up to temp. I used a heavy pair of leather work gloves to push on the area I needed to deform. Once you get it to deform hold it there for a few minutes until it cools and sets. Put your tank back on and check the clearance repeat as needed.
If you need more clearance and don't want to deform the tank additionally, you can cut a piece of 1/2" thick rubber and glue it to the rear rubber tank / frame bumper. This will raise the rear of the tank just enough to get the clearance you need.
I am also still making the adapters for members who request them. If you want send me a PM and I will get back to you asap.