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Valve War

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When ever a manufacturer improves something on there bike that gives them the edge whether it be susp, motor, etc.. it does not take the other guys long to step it up. I know every brand has there pros and cons for what ever reason but I do not understand why none of the other brands have followed suit behind yamaha on the valve thing. I'm not a mechanic so I dont know if its the argument on better quality metal or the fact they run five valves and not four. I just know from what I see on the boards etc.. over the last few years yamaha's don't need adjustment near as much as everybody else. I think all brands have great bikes but over the course of a year I had my crf450 adjusted four times while my friends yz450f at the end year were still with in spec. Needless to say that even though I would like to try a susuki, or maybe a ktm, my next 450 will be a yamaha just for the fact I wont have to worry about valves but once a year or so. We all have to change tires, brakes,seals etc.. but you would think that if yamaha is winning the reliability factor in the valve department the other brands would want to be of at least equally competitive. Just tired of adjusting valves more than my chain is all. :thumbsup:

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I’d like to understand the differences in valve reliability between CRFs and YZFs. It would be hard to tell from a forum like this because most people don’t typically start treads on the subject until they run into a problem. Honda sells a lot more 450s than any other manufacture so of course there are more CRFs running around out there with valve problems. There are a lot of opinions, but I’m not sure how to really tell which bike has a more reliable valve train.

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I’d like to understand the differences in valve reliability between CRFs and YZFs. It would be hard to tell from a forum like this because most people don’t typically start treads on the subject until they run into a problem. Honda sells a lot more 450s than any other manufacture so of course there are more CRFs running around out there with valve problems. There are a lot of opinions, but I’m not sure how to really tell which bike has a more reliable valve train.

Your right, its a fact there are more CRF's sold than YZF's. But if you randomly pick 100 owners of each brand and question them about reliability you will find the YZF's valve train is far more reliable than the Honda.

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It must be our climate here in NC because out of the two valve failures that my personal friends have had both were YZ250F's.

I have 5 friends with CRF450's, 2 CRF250's, 2 YZ250F's, & 4 YZ450F's. :thumbsup::ride:

After Anally checking mine for 3 yrs now with no movement I have been led to believe what I see more than what I read.

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alot of it comes down to how hard you work your motor. these are all pretty much works race type engines and if you race them hard no matter what brand your on valves,cam chains should be checked fairly regular.it's all proportional to the amount of abuse.

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This is such an age old question and is flogged with opinions. I have friends with basically all brands and niether of us have had to adjust/shim our valves any more than the next guy. What we notice is the performance differences more than the maintenace ones. My CRF has never had the valves adjusted and are not even close to being out of spec. Two fo my friends had to adjust theirs, but just once so I don't considder mine any more reliable or better than theirs. They rode a YZF and RMZ. My buddies KTM 450 has never had to adjust the valves but the jetting has been hell. Maintain your bike and it will take care of you. :thumbsup:

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^^ If that was it they would probally make em in the US. There are USA factories that make Hondas and what not. Might not be bikes but if it came down to that Im sure they could.

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Your right, its a fact there are more CRF's sold than YZF's. But if you randomly pick 100 owners of each brand and question them about reliability you will find the YZF's valve train is far more reliable than the Honda.

I guess thats my point. If you go to the treads on this site alone on valves you will notice that the yamaha's dont seem to be as long listed as the other brands. Yamaha seems to be getting a good reputation for how long there motors can go without needing adjustment. Im not brand loyal and alot depends on abuse and maintenance I know. For instance I went to a ktm dealership and the guy there explains that ktm uses a much better quality metal than the other guys and says after the first couple adjustments they can go along time before they need it again. Fact is on this website or even ktmtalk they need adjustment same as everybody else and just as often.

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Your right, its a fact there are more CRF's sold than YZF's. But if you randomly pick 100 owners of each brand and question them about reliability you will find the YZF's valve train is far more reliable than the Honda.

That’s the kind of opinion that I am talking about. Unless you’ve done your own polling, you can’t say for certain that the YZ owners will not have as many valve complaints.

Even if you did ask 100 owners of each brand, they would all have to be riding on the same level with similar riding styles and similar maintenance routines.

I would like to know if there is a difference in reliability because it will definitely affect my next bike purchase.

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is it possible that the UniCam design used solely by Honda has anything to do with it? how are the RMZs and KXFs?

why is it that motocross 4-strokes need such frequent valve adjustments? they dont rev particularly high. 600cc street bikes rev to over 15,000rpm now and i've never heard people complain about frequent valve adjustments on them. just curious.

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For instance I went to a ktm dealership and the guy there explains that ktm uses a much better quality metal than the other guys and says after the first couple adjustments they can go along time before they need it again. Fact is on this website or even ktmtalk they need adjustment same as everybody else and just as often.

yamaha uses a shim/bucket arrangement, which tends to stay in adjustment better just because there are fewer parts. ktm, berg, husky, honda and some others use more of a rocker arm type arrangement where the cam is connected to the valve through other machinery. more stuff to wear, but also easier to adjust (no need to actually remove the cam).

i can do the valves on my husaberg in 20 mins or so. it's so easy i almost feel guilty going 1000 miles between checks.

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That’s the kind of opinion that I am talking about. Unless you’ve done your own polling, you can’t say for certain that the YZ owners will not have as many valve complaints.

Even if you did ask 100 owners of each brand, they would all have to be riding on the same level with similar riding styles and similar maintenance routines.

I would like to know if there is a difference in reliability because it will definitely affect my next bike purchase.

I really don't need to start a poll about reliability. I bought my 426 brand new in December of 2001. I do all the maintenance myself. I ride the bike very hard also. So far, nothing out of the ordinary has gone wrong with the machine, including the valves.

Whats my next bike going to be?......A YZF of course, why should I take the chance on another brand since the YZF has been so good to me? CRF's look good, but I have seen first hand too many valve and counter balancer issues for me to buy one.

IMO, Every manufacture makes a good bike, but only one manufacture makes a great bike.

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