When the yfz acually runs 1/4 of the time its a great bike but since it doesnt run and has many problems its a pos.

Grinder04,
I have the same bike and I had a similiar problem, you may have already checked but check the ventilation tube coming from the fuel cap. Mine was pinched so no air could get into the fuel tank causing vapor lock. I know it is a basic suggestion but I hope it helps, if not get the carb cleaned.

i have a 2006 YFZ 450. I have had it for 2 years and no problems. I have a new axle new rims and tires. Last week I put a slip on exhaust on it and i love it, rejetted it also. I was riding yesterday and we were crusing about 4th and 5th gear, and it wanted to cut out, so i stoped to listen closer and it died and wouldn't start back, i waited for 10-15 mins and i started back up for a few seconds and then it died and wouldn't start back up. Pulled the plug and it was clean and brown from burning awesome. Any ideas??

once you go blue...hondas threw

I am in the market for a yfz 450, but im wondering since im 260 pounds if its a good choice for me..... wondering if there are some big yfz boys out there??!!

yfzs are the worst i had mine for 1 hour and it blew into a million pieces and the yamaha guys said that happens all the time and theirs nothing they can do about it even though i had a warrenty!!!!!!! even the guys at the yamaha shop told me to buy a honda i bought the honda and right out of the box it must have been doing like 200mph it was very fast

my yfz is fast if got it up to 97 mph i have it jetted, piped, nerf bars,shocks,metal tech a-arms,dg front bumper,itp tiers and wheels,hand gards,skid plates, it is a fast atv

I just bought a 2006 left over yfz450 about a month ago i must say its 1 sick machine seriously. But i have a problem that happened about yesterday i was riding and i was fallowing about 20 people and just cruising in 5th hear for about 5 minutes and it wanted to shut down it kept bogging out and wanting to shut off and i went to stop. It wont let me take off right i have to keep it in a really high Rpm and beet the hell out of it to get back to my truck it still took about a half hour and yet ll it wanted to do and it did was bog out and cut off on me its kinda hard to explain but does anyone have any suggestions about to what it is?

i bought my yfz when they first came out and well i have put about 15,000 into it and i have never been beatin by anything on the track ! even before i did any major work to it it kicked butt . i have to say the best upgrade to it was full elka suspension .this bike was the best investment i have made as far as fun goes .

I have a '06 yfz 450, and i also own a '06 trx 450r. and by far the yamaha beats the honda right out of the box. ive done limited changes to both. ive put a full pipe with header on both, with the skid plates, the nerf bars, rejetted both of them and the yamaha still beats the honda on the track. i run faster lap times with the yamaha everytime. this quad is truely one of the best quads ever produced, ive owned a yfz 450 ever since they came out, before that ive owned a 660r, a 400ex, z400, any sports quad you can think of and this 450 topps them all

dude i have been at gordons with my all stock YFZ like every weekend and the only thing that has beaten me is other YFZ and suped up banchees it is a fast bike

ltr 450 suzuki.i need not to say more.

I've had my YFZ for over a year and I haven't yet met a stock quad to beat me. I've smoked the 450R, Suzuki 450, the polaris predator. The only quad close to beating me was a highly modified banshee. I don't care what anyone says, a stock YFZ will smoke anything out there as of today. If you disagree, meet me at the track at Rauch Creek, PA and I will prove it to you!!!

I just got my new yfz ABOUT 3 WEEKS AGO. IT SUCKED WHEN I HAD TO BREAK THE MOTOR IN FOR 20 HOURS. ONCE IT WAS BROKIN IN IT WAS THE SWEETEST QUAD IVE EVER RIDDIN IT HAS ALOT OF LOW END POWER ONCE I TOOK OUT THE BAFFLE IT GOT LOUDER AND IT WAS MORE RESPONSIVE. IT GOES ABOUT 78 MPH STOCK WITHOUT THE BAFFLE IT GOES 81 IT IS AMAZING IF YOUR LOOKING TO HAVE A SCARY FAST, AWSOME DUNE AND HILL CLIMBING QUAD THEN GET THE 06 YFZ 450 ITS INCREDIBLE.

My yfz 450, with about 35 hours on it, just blew up!! The piston pin came out, broke the counter balance, someyhing put a hole in the top of the tranny. It's a complete loss. It's my first and last yamaha. Total garbage!!!

Regaurdless of what atv you decide to ride. How good the rider is, decides which bike is faster or better. Also anybody can put thousand s of dollars into thier quads and blow each other away but lets look at the bike at stock level.


YFZ 450-------------------
Bore x Stroke-95mm x 62mm
Carburetion-Keihin 39mm FCR w/ Throttle Position Sensor
Compression Ratio- 11.9:1
Drive Train- 2WD; Sealed O-Ring Chain
Ignition- DC - CDI
Starting System- Electric
Transmission- 5-Speed Manual Clutch
Type- 439cc, 4-Stroke Single, Liquid Cooled w/ Fan, Titanium 5-Valve DOHC

TRX 450R------------------
Bore x Stroke-94mm x 64.8mm
Carburetion-Keihin 42mm with Throttle Position Sensor
Compression Ratio- 10.5:1
Drive Train- 2WD; Sealed O-Ring Chain
Ignition- CD with electronic advance
Starting System- Forward Kick
Transmission- 5-Speed Manual Clutch
Type-450cc 4-Stroke Single, Liquid Cooled

660R RAPTOR--------------
Bore x Stroke-100mm x 84mm
Carburetion-Dual Mikuni 33mm BSR Compression Ratio- 9.2:1
Drive Train- 2WD; Sealed O-Ring Chain
Ignition- DC - CDI
Starting System- Electric
Transmission- 5-Speed Manual Clutch w/ Reverse
Type-660cc, 4-Stroke Single, Liquid Cooled w/ Fan, 5-Valve

There are the fact! they all are very close. One thing to keep in mind is with the electric start you have to deal with the batter possible going out, than your screwed if your out riding and that goins out. However, some newer quads have higher compression which need to have a battery to compensate like the 2006 450r.

very fast sucks on trails. not much of a wheelie machine. and nose dives when you jump it. but its got tons of kick ass power.

06 - stock. Very Fast machine. I took the lid off the airbox and no bogging anymore, you can feel a little more power already. My rear shock is leaking already, Ive only had it for about a month but ive some pretty good air on it. I got a service plan...so yamaha will pay for the shock. Anyone recommend any specific pipe for it? I live in Vegas, and ride the trails and dunes at APEX. Great time, havent raced any other 450's yet, but it will kick everything elses butt!

a friend of mine has a yfz, I must say it is an awesome quad to ride but i will take my honda 250r any day. i have heard from a lot of pple sayin that they have top end trouble and trouble getting oil to the crank. none the less very fun/fast quad, just needs to be a bit more reliable

iv got a 06 yfz 450 with pipe and air filter kit iv had nothing but problems with mine since the day i picked it up falls on its face at a idle..

yamagay sucks dick

I rode the yfz450 today and i was so impressed on what yamaha did to those things... the only thing i didnt like about it was that the reas sat way to low and hit every little rock.

The YFZ 450 is opne of the the best sport quads ever made. I am a strict yamaha and i can also give the honda props. Its a fast quad too, but more trail oriented. Both modded they are equally deadly in the dunes, on the track, or in the woods. Anyone that says they has yet to ride on or is just jealous because they dont have one.

the yfz 450 is the baddest fourwheeler out there anybody that says that a stupid ass 660 raptor is badder they obviously havent rode one yet

Excellent bike very fast.

I am an all out honda. I havent been beatin by a yfz yets(noticed i said yet) but there were saome that i almost gotten beatin by. I went to pymatuming the week or what ever after a freind was lost(died racin his honda 250x) and me and this kid from Sharon PA gave me a good race.All day people were comming up and sayin that that was the best race they ever seen.Yamaha YFZ450 are a very fast bike.Not mebnt for unexpirenced rider.My hats of to people who ride yfz.VERY VERY LIGHt.SUspineson could be a little wider and lower,Plus a little stiffer.

have had mine since feb 04 (still 4 months before the honda even showed up at dealerships) have added full ct kit (junk threw it away, worst $600.00 I ever spent) A dr D slip on (best $285.00 I ever spent, so impressed I bought one for my son's raptor)pro flow k&n filter kit (very nice product) & did cam mod (very easy & free). I ride the dunes in mose lake, wa & have yet to beaten by anything other than a 420 banshee & a couple of other yfz's (have raced built predetor's, trx 450r's, ds650's, anything that would line up) . I took 3rd in a 18 mile cross country race my first time ever racing quads (this is my first 4 wheeler). I found it quite interesting that out of 44 quads on the starting line, yfz's took 1st -5th &7th-11th, there were only 12 in the race. trx 450r's (there were 13 that started) finished 6th & well I don't know, I didn't stay long enough to see them finish. Well any way the only problem I have had is my son likes to leave my key on & drain my battery, (after riding a friends trx I would rather pull start my yamaha than kick a honda!!!!!!!!!!!)

Well i have to say that this Quad sucks Along with the honda 450r ... sorry to say but my 86 honda 250r will smoke any yfz or 450r. to bad they weigh so much and have to have twice the displacement as a 250r. plus 2 strokes are always lighter. less weight = more speed, ill put my r up against any 4 stroke, i promise ill be waiting in the end. Its just so pathetic.

wow just got one and does it rip. its amazing best qaud i riddin yet. i bought it off someone and at the end of almost every gear it bogs a little, anyone kno whats up with this?

I am HONDA to the bone, but the yfz450 is an all-around kick-a@* machine. I have no problem admitting that Yamaha makes one hell of a competition, in some aspects better than Honda. I say if you RIDE it's all good. RIDE ON!!!

I LOVE THIS QUAD!!! I just got it about a month and a half ago. My b/f will most likely race this quad instead of his Honda TRX 250R, if for no other reason than THIS QUAD FLIES!!! The ONLY thing that bothered me at first about the quad was the thumb throttle and how tough it is on you on long rides. But I am getting used to it. Hey Raptorman89 - I take it that you live in PA? I just learned of Rauch Creek yesterday - how is it?

my 14 year old brother had to ride this quad(which is my dads) because his blaster was still getting fixed with new parts. he got 2nd place with this! and my dad rides this quad and he does really good on the hole shot and doesn't even have custom parts exept for an axle which doesn't in crease the speed really. this quad kicks @$$

This quad kicks ass. I rode my neighbors yfz and i was at rauch creek beating everyones butt with it. The best quad ever

it could posably be the worst atv ever!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!1