Yamaha's amazing reliability!

Just finished checking my valves all in spec! Haven't had to adjust them since i bought the bike in 03 :applause: Never again will i ever have another bike, besides yamaha.

i'm on my 3rd motor on my 03 thanks to a bad factory rod bearing with no help $$ from yamaha, then after a complete top and bottom rebuild 10 minutes into 1st ride motor blew up again cuz of detenation in the cylinder. once again no help from yamaha or yamaha dealer. love the bikes &%$#@! the company or corporate or whoever they are. bitches

I've heard many many many stories like 450 Rider's and less than a handful of stories similar to rasta. Rasta, I'm sorry to hear abour your experiences, but the law of averages say it won't happen again if you buy another blue. They're wonderful bikes!

I've heard many many many stories like 450 Rider's and less than a handful of stories similar to rasta. Rasta, I'm sorry to hear abour your experiences, but the law of averages say it won't happen again if you buy another blue. They're wonderful bikes!

that is true,i just have bad luck, always been like that but anyways i am getting a 06 wr450 for the street here in ca, since i have a red sticker bike and have to travel 2 hours to ride on the dirt, i have not rode anything yet that feels and pulls like a 03 450, my 02 was close.

I love my '02 YZ426, but...........the intake valves have been tight and needed shimming three times since I got the bike used last year. :applause:

I love my '02 YZ426, but...........the intake valves have been tight and needed shimming three times since I got the bike used last year. :applause:

You might need to look at replacemen of the valves then since it seems they are stretching pretty quick.

Metal stretching. What a funny concept.

I love my '02 YZ426, but...........the intake valves have been tight and needed shimming three times since I got the bike used last year. :applause:

Unfortunately, unless you know how the bike was maintained before you owned it, all bets are off when buying used.

Unfortunately, unless you know how the bike was maintained before you owned it, all bets are off when buying used.

The previous owner was a friend of mine and I know he treated the bike well and maintained it often. Unfortunately however he ran the bike with a K&N airfilter which I'm certain was the culpret in wearing the intake valves so much. This most recent valve adjustment was since I went back to a properly oiled foam filter so I'm just hoping it's the last I see of the negative effects from the K&N.

Bought an 04 new and the valves have been perfect.Only things I' ve had to do is replace 2 :applause::ride: rear tires.No defect in the tire i just use the heck out of this bike.

Just finished checking my valves all in spec! Haven't had to adjust them since i bought the bike in 03 :ride: Never again will i ever have another bike, besides yamaha.

I bought my '99 YZ 400 new in 99, and checked valve clearance in 2004 for first time. :p They were all within spec :applause:

Ron D.

I bought my '99 YZ 400 new in 99, and checked valve clearance in 2004 for first time. :p They were all within spec :applause:

Ron D.

Now that is amazing............ :ride:

Now that is amazing............ :applause:

Yeah it is.

sincerely,

CRF 250s

I bought my '99 YZ 400 new in 99, and checked valve clearance in 2004 for first time. :ride: They were all within spec :applause:

Ron D.

That's awsome. What's funny is you hear Honda guys bragging about how great their valves are holding up when they are still in spec 40 or 50 hours later. I'd like to see a Honda guy (not an XR) with a similar story. Oh, thats right, Honda didn't make a MX thumper in '99. :p

I love my '02 YZ426, but...........the intake valves have been tight and needed shimming three times since I got the bike used last year. :applause:

You need new valves, they will keep going out of spec until they break. Dirty air filters (or clean K&N's) caused the coating on the valve to wear off.

You need new valves, they will keep going out of spec until they break. Dirty air filters (or clean K&N's) caused the coating on the valve to wear off.

I have been using my K&N for last year or so it hasnt harmed my valves at all, or am i just lucky?

You need new valves, they will keep going out of spec until they break. Dirty air filters (or clean K&N's) caused the coating on the valve to wear off.

Actually the one intake valve that had been out of spec the most was OK this time but my mechanic said the other two were right on the border so I had him adjust them. If they're all within spec now and I'm not at the last possible shim allowed, do you think they'll be OK for a time or am I courting disaster?

I have been using my K&N for last year or so it hasnt harmed my valves at all, or am i just lucky?

The pro's and con's of K&N's have been debated on other forums here at TT. The general concensus is that they do not filter the really fine silt that can get into your valves.

The pro's and con's of K&N's have been debated on other forums here at TT. The general concensus is that they do not filter the really fine silt that can get into your valves.

Oh I see, where I ride its always raining, or on gravel logging roads, but I think i might just want to get a new filter, don't wont to worry about my valves.

Goose, if your valves have had to be adjusted three times in a year, you need to replace them before you drop one. If you do drop one your parts list will most likely include a cylinder, head, cam, crank, piston, rings, etc... My riding buddy had his let loose after 250 hours on the motor. These motors are tough, but it's giving you a sign you should heed.

As far as K&N filters go, the only way to flow more air than a stock filter is to filter less. It's simple physics. Is whatever minimal power you gain from a K&N filter worth it?

I'm on my 3rd YZF and the only engine work I ever did was on my 99 YZF400 when I did the piston and rings because the bike had 3 years of ALOT of riding on it and I thought I should. The piston was fine, the rings were ready though. I know there are bikes out there that will out handle my current 03' 450, but they won't outlast it or beat it up the hill. I'm amazed they get this much power out of the motor yet it's still stone cold reliable...

I have been using my K&N for last year or so it hasnt harmed my valves at all, or am i just lucky?

Your lucky, or the damage hasn't been found yet.

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