yz450f for off-road duty??

High guys, I'm considering possibly getting a yz450f to ride off-road. I could possibly race some hare scrambles, but it would mainly be for my own single tracking and recreational riding. Right now I'm used to 2-strokes, and i could go with a yz250 because of love the lightness and how the 2-stroke operates in the woods. But i've always wanted a bit more torque, traction and top speed for other applications.

Im wondering, who here rides the 450 off-road, and what do you think of it's off-road manners? I'm afraid of it being too brutal, to heavy, or not good at chugging at low speeds without stalling or flaming out. or all three combined. Does the stock yz450 have a leak jet? or does the carb need some modification to run healthy at low speeds?

Im also worried about maintenance. What should i expect to do on a daily to weekly bases with a 4-stroke 450? I understand the yamahas are the most reliable (give or take a few lemons).

Also, what year did the alloy frame start. and what year were the 450s 5-speed?

oh and for the record. i'm 6'1, 210lbs.

I run a Yz450 for sand dunes only. Never been on an MX track.. It works for me.

As far as tight stuff, lots of people on here use a recluse autoclutch to allow them to ride over terrain where they need to vary speed a lot and go slow sometimes.

The bike doesn't like going slow for long periods as it can overheat.

Other than that it is great..

I have about 50 hours on my '07 yz450f, all off road in the Arizona White Mountains and high desert:

1. Off road manners? Not too brutal, too heavy, or prone to stalling at slow speed if it is properly jetted. Many threads about jetting at this site. Replacing the pilot screw with an after market thumb screw is recommended; no other mods. are necessary to get it right.

2. The bike is not too demanding for maintenance. Searching this site will help in deciding for how extreme you want to be. Suggest change routing of the crankcase breather hose to a higher location, and filter it. This will eliminate the risk of pulling contaminants into the engine when deep in sand or water. Also, install a hour meter for consistent maintenance intervals.

3. Aluminum frame and 5 speed was introduced in 2006 on the 450.

4. My bike has been 100% reliable so far.

I ride/race an '06 (first year of aluminum frame and return to the five speed) in the NMA offroad series and I absolutely love it. Many of our races here are in very tight and technical areas and I have yet to lose any coolant. The power of the '06 YZ450 is so smooth and linear that it is an excellent offroad motor IMO. I came off an RM250 smoker that was set up very well for the woods so I can make the comparison to a 2T.

I have done the Zipty Racing carb mod and that combined with proper jetting makes bogging and flameouts a non-issue. I also run the Rekluse z-start pro auto clutch.

I run an 06 in Michigan, trails and hare scrambles only no mx. My bike is bone stock except for a slip on 96 db spark arrestor. My bike runs flawlessly in the trails but I would recommend a rekluse clutch. I dont have one but in the tight stuff it would be useful. I would also like to try a heavier flywheel. I run Rotella T and change it every ride. $12 a gallon vs. $10 a quart for synthetic. I have had no issues with the lube. Also it is very very important to reroute your crankcase breather tube that comes from the top of the head to your airbox and put a filter on it. Mid way through (at the lowest point) put a tee with another(smaller) hose running down.

Alright, the 06 is what I'm looking at. If it were up to me i'd get a ktm 300 2-stroke. but yz250s and yfz450s both seem to be about 1000-1500 less on the used market for the same year (2006). So im thinking blue might be a good option.

also, my brother has one of those yfz450 quads. and i'd like to smoke him with similar genetics.

But i'd still like to hear some off-road testimonials, so by all means i'd like to hear some more.

I ride/race a 2006 4fiddy. I like the tight, technical, and nasty trails. I think it does a great job in this stuff. The best thing I've done to it was getting the suspension set up properly (sprung for your weight and revalved for the type of riding).

I have about 138 hours on the bike and it is still bulletproof. I checked the valves at 118 hours and it was on spec. No adjusting necessary.

BTW... I did a crazy ride with some killer riders at Clear Creek, California. It is a pretty gnarly area. Long story short, there were at least 12 KTMs in our group and my buddy on a CRF450 and me on my YZ450. Guess which bikes were overheating? For some reason all the Katooms were puking coolant and steaming like crazy when the goin got tough. I lost a little coolant, but didn't steam over at all. My buddies CRF was fine all day, too.

I was envying the electric start though.

Thanks for reminding me NorCal. I totally forgot to ask about starting. Is it an issue? I've always read and heard about how hard it is to start 4-strokes when they're hot. Is it an issue with the 06 and up? My 2-stroke was easy to start, but after a gnarly muddy section, starting it over and over could still wipe me out.

Thanks for reminding me NorCal. I totally forgot to ask about starting. Is it an issue? I've always read and heard about how hard it is to start 4-strokes when they're hot. Is it an issue with the 06 and up? My 2-stroke was easy to start, but after a gnarly muddy section, starting it over and over could still wipe me out.

No, it's not an issue if your jetting is correct and you use proper technique. Really, it is all about just kicking it over at top dead center. It is harder to start when it is in gear. My races are always dead engine starts. I put it in 2nd gear and make sure it is at TDC. Once the gun goes off, I grab the clutch and hot start simultaneously and give it a quick kick. So far it has fired first time, every time (knock on wood).

See, i get all mentaly prepared to get a 450 and make the swap to 4-stroke but then i read stuff like in the new dirtbike. they test a yz285 in the new issue and on the first page it says something like "after riding around a heavy 450 all the time, we forgot how good it felt to ride a light peppy 2-stroke".

^ I know what you mean! Confusion!

Previously owned an 00 426, now ride an 06 YZ 450F, both are 100% woods machines. NO complaints whatsoever from me. My 06 isn't set up perfectly yet, but it's dang close even with stock suspension. If you are serious into woods riding, you'll want at least the following stuff: handguards (recommend a triple clamp mount, I have GYT-R and really like them with Acerbis Rally Pro handguards), taller bars (for your height, I'm 6'2" and run Windham Pro Tapers with 10mm risers and really like them), rad cages (Works Connection for me), skid plate (also WC), good chain (X-ring or similar), and a decent front tire (Kenda Washougal on mine). I have a bunch of other stuff too of course, most of which helps but isn't necessary. One thing I do recommend though for the 06 is the GYT-R off-road flywheel, makes the engine harder to stall in the tight stuff, yet doesn't really seem to affect the power delivery. If you want PM me and I can tell you everything I've done to my 06. It's a pure woods bike, never seen a track once in its life.

And, don't listen to the rags, I honestly don't think you'll notice the weight of an aluminum framed 450. I rode a 2-smoke 250 a few years back and it felt so dang underpowered compared to my (then) 426 that the extra weight didn't bother me a bit. The 450 is so light and easy to ride/move around it's silly. Make the jump, you won't regret it.

I can't tell the weight difference between my '07 450 and 250.

I like the 450, because the 4-stroke power delivery suits me better.

When the 250 gets up on the pipe it can be a handful.

i ride mine(04 yz450f) in single trail and just off road riding and i love it. i coulda gone with the 250 4 swtroke which is good for the tighter stuff but the 450 goes good on the open parts.. u will find the power very good and you can just use lower gears and the clutch more in the tighter stuff.

if your looking for traction then the 4 Stroke is it, if you want lite, flicky, really low CG then go with a 2T...

I had both, and no matter what my 07 YZ 450 "feel's" like a tank compared to my YZ 250... But! the damn 450 motor is a tractor and really makes things easy when the going gets tough...

I like the 250 cuz its flicky and peppy, but I feel my 450 simply owns it when it comes to traction and torque..

I had to go to 12/52 gearing on my 08 to get it to go through the tight woods. But I also like a hard hitting bike too. Bike handles great in the woods.

I had to go to 12/52 gearing on my 08 to get it to go through the tight woods. But I also like a hard hitting bike too. Bike handles great in the woods.

Holy cow, that's low gearing.

My YZ 450 is awesome in the woods,GYT-R FWW ,1 tooth up on the back sprocket zip ty carb mod,and just got the recluse clutch yesterday .Stock suspension with a little tinkering.I love the power of the 4 stroke compared to my YZ 250 2 stroke.i don't notice much weight difference,Because i cant ride them at the same time lol.Here in Western Washington we have some pretty good tight&technical single track trails and the 450 is what i like.:cool:

i have about 140 hours on my 06 yz450 and thats all on the tight trail i dont really ride anythin ealse and i love it.

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