What to do with a Honda CRF X model to make it run a lot better. These are great bikes that last a very long time and with just a few inexpensive mods they really can rip.
I bought my 2014 450x new and it was super lean out of the box and was hard to start cold.header pipe would glow red.I just wanted my bike to run good but basically stock for reliability reasons and they have plenty of power as is(for me at least).After asking a bunch of mechanics and reading online this is what I did.I removed the smog pump,made the block off plate on the head out of 1/4" aluminum plate and plugged the airbox and other holes with bolts I had.I made the airbox plug from a bolt with electrical tape wraped around it until it was the right diameter.Then I bought the same dial a jet as the one in this video.My 2014 model had a plug fused in the carb body that I had to drill out carefully to install the dial a jet but I managed with a dewalt cordless drill and some patience.no jet kit,stock exhaust and certainly didnt destroy my airbox(I ride thru rivers and mud constantly).These 2 things corrected my air fuel mixture and made for easier start ups,more power and smoother throttle response.Dial a jet cost $30 something dollars and the smog pump delete cost $0. Hopefully my 5 minutes writing this will help someone lol. Save your money for back tires and learn to ride better cause we all know its mostly the rider and not the machine.
I have had Multiple 05 450x. No need to cut and destroy the air box, just pull off the top cover snorkel. 2nd on the pink wire mod above the connector is a blank empty hole, pull the pink wire out put the pink wire in the empty hole and put the rubber grommet where the pink wire mod was, that way the wire is not cut. Jetting is a good idea too I just do a 45 pilot and a 165 main. and then I pull the baffle out of the exhaust cut and re insert the end to open it up too,
I'm at sea level and I ran a 180 main jet and it made a huge difference over the 160 I had changed out the first time I pulled my carb. If your at sea level or low altitude I highly recommend a jet between 178 - 182
I have just completed all these mods to my CRF 450x 2005 including the jetting . Then took the bike out for a 3 day 600 Km Advanve ride. It was like riding a totally different bike, more responsive quicker
I have an 06 450x and it is really good for open stuff. In the slow stuff not so much because it stalls easily and no hydro clutch. It is a quite violent power delivery compared to my ktm xcw450 2009. It is a very solid bike start right up every time and does not over heat ( ktm does). I have put a tubliss with a trial cheater tire in the back at 10 psi and now it is plush and grippy. Only issue is it is sometimes hard to shift into 4-5. I ride mostly 2-3. Any reason why ?
Great easy to follow vid. Cut my air box today and put a fresh plug in my 06 450x. Haven't got to the carb yet.......but will before I ride it again. The air box cut must really let a lot more air in. I fired my bike up and noticed the header pipe glowing red, so it's for sure running lean now lol. Not sure if I'm comfortable tackling the carb myself or just take it to the honda shop.
The CRF 450 X 05 air box is different to the 06 . On the 05 the battery tray is mounted n the top section that you cut out. Where was the battery tray on the 06 bike you used in the video?
Honda marking were to cut? they did that on 250s in the UK in the 60s and 70s, the carb slide was limited, open the carb and on the rod was a line.......you guess it..........marking where to cut to derestrict
I have done most of the mods on my 450x. I don't know about the pink wire. I need to check on that one. I have been having carb problems and wanted to know what product you use to clean it. I made all the mods when it was brand new and it ran so well. Very strong. It is just the bad gas that killed me by sitting for a couple years. It was a sludge pile in the tank. I had to buy a new tank. I have pulled that carb off so many times and even bought a $500 sonic cleaner with no luck. Bought new jets, etc. I have a parts washer, but I use this water based cleaner due to being in California. I think I just should move back to a petroleum based solution to fix it up.
Awesome video! Love the info. I have the same carburetor but the accelerator pump nozzle (that squirts gas when the throttle slide opens up) is all clogged up. I tried spraying carb cleaner and compressed air through the nozzle but it's still clogged. Do you have any tips or tricks to help? I would just get a replacement nozzle but I can't find any replacements anywhere online.
Well this can cause a carb to be totally worthless and no you cant buy a new nozzle. I have a good Mechanic friend who helps me and we have run a hand drill with our fingers in there to help but we have ruined some as well. At this point it can be your only hope. The drill bit is .010-.014" range-- very small you can barely see it :-) good luck--
Don’t cut the pink wire. The engine retards timing to protect itself from detonation at higher loads. The ignition mapping in these bikes is actually pretty cool. Sure you might get more power but the bike’s piston and rods wont last as long
Now my air filter gets dirty quickly all in one spot(I only cut the top of box directly under snorkel). The snorkel distributed the air flow deeper in the air box which lets more surface area of the filter be used. I only ride trails and lack of power is NOT an issue with a properly tuned 450x. Another added benefit to not cutting the air box is the stock setup is excellent for water crossing. All just my opinions/experiences from eastern USA riding.
on my crf450x 2006 I only mounted the exhaust of the crf450r 2008 without opening the filter box since I don't need extra power here in Italy, the carburetor jets keep the originals 142 main jet, 45 slow jet, 70 starter jet, or should I increase them? thank you
I think you will need to go richer jetting with a muffler-- I would still open up the air box as it will run better-- with the muffler on now does it pop as you let off the gas- -if so then needs to be richer.
@@dirtbiketv1 first of all thanks for the reply. Exactly, when I release the gas it pops, should I only enrich the main jet like in the video or also the slow jet to 48? thank you very much
hello I have a 2005 Crf450x with a 500cc big jug head, and yosh exhaust. I did all your recommended mods and now im at the carb im 1240 ft above sea level. Should I run a 160 or 162 main jet , a 45 or 48 pilot jet and you said use two 0.5mm shims which would make it 1mm total. Is that correct. I purchased a all balls carb rebuild kit and a nicecnc air fuel screw. Appreciate your help.
No it does not, but it raises the rpm limit. You will notice the difference. I actually put a small waterproof switch in mine so I can have two modes. The stock mode (pink wire connected) is good for riding in mud, snow etc., or slow tight trails. Everything else having the wire open is much better, at least if you want more power & higher rpm limiter.
@@mayorbillyt the pink wire on the carby models only. The pink wire goes from the ignition timing to the cdi unit. Note this is only for carby models that are the crf250x and crf450x👍
You’re going to reduce air velocity into the big MX carb because you cut such a large hole. You’ll actually get more peak power, and less bog, if you cut around half as much out. You’re losing too much velocity.
Good point. All the bottom end goes away because of a big bog, If you reduce venturi vacuum to nil the motor will fall flat when you open the throttle.
No place to -- yes you could go in and find that pin and undo it but you risk messing with the others-- easier to just cut as we will never put it back-- I assume you wouldnt either after riding it :-)
I went through my 450r carb last Friday. Still won’t run off choke. Everything points to the pilot jet but it’s clear. I can only assume the passage above it is blocked. When I looked up there I don’t even see a passage. Got any ideas on where or how to fix this?
@@dirtbiketv1 oring mod , airbox and jet it correct. I've heard this pink mod some years ago and everyone raved about it. So naturally I did it. But couldn't feel ANY different from before
People don't do these mods, sure they get a few extra HPs but you whack the emissions out and end up needlessly contributing to global warming, if you want a little extra punch buy a different bike that has been properly engineered and leave it alone.
Supra anon - You seem like a nice enough guy but you are confusing weather with climate and most people do. My first job out of college (92) was at the EPA environmental super computer center (NESC) where we did environmental modeling. This was at a time way before global warming was main stream, hell it was before Al Gore. I will just tell you that our models predicted what we are seeing today and research since has validate those findings. Our planet is getting warmer and we are seeing the effects of this more and more every year. It is up to each one of us to do our bit to save the plant for our kids, I ride dirt bikes and I do it responsibly. When I buy a used dirt bike I return it to stock conditions, eg I put the emission (smog) components back on my XR650L, I went back to factory jetting on my KTM EXC 450 with factory exhaust and it works just fine and the next bike I buy will be fuel injected and I will run the factory maps.
Michael Katt it’s really good of you to think of home like that 😎 not many do now days and weather the climate change is a hoax or not well done 👍 What ever this is we live on or in we all really do need to look after it .
