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Marauder
Mon Jul 31st, 2006, 12:39 PM
I was looking at the Yamaha website the other day and noticed there are "Dirt Bikes" and "Motorcross" bikes. I guess I am nieve...I thought they were the same. What's the difference between, say, a Yamaha WR205F "off-road" bike and a YZ250F "Motorcross" bike. I was thinking about dirt riding.

chadincolo
Mon Jul 31st, 2006, 01:31 PM
WR's have lights, heavier flywheel (bigger mag), different timing on the cams (less hit), and are typically quieter, softer valving on the shocks... I'm sure there's more. YZ's are more high strung, race bikes. You can do motocross on a WR or trail ride a YZ, but they are a little out of their element, even though they are almost the same bike.

Bueller
Mon Jul 31st, 2006, 03:51 PM
YZ-screams, WR-is a tractor
YZ-Motocross, WR-trails

I like my YZ on the trails 'cause it screams :rock:

Marauder
Mon Aug 7th, 2006, 11:54 AM
Ok...pardon my ignorance. I am interested in dirt riding but know nothing about it. What is all this talk of 2-stroke vs 4-stroke? I was told I want a 4-stroke but I would like to know why. Also, I know nothing about trail riding. All I have seen are the courses on I-25 up north and east of E-470 on Jewell. Do people take trail bikes to the courses? Like chadincolo said...would I want an MX bike instead of a trail bike if I wanted to do both?

Bueller
Mon Aug 7th, 2006, 05:03 PM
The difference in the motors is a lengthy explanation, with multiple options.
The choice of bikes would probably be best based on what you will ride the most. If it will be the track then the choice would be MX if you feel that trail ridding will be your preference, then I would get an enduro style.
They will both do it all, but the specific bikes are much more adept at their jobs.
If you plan on doing much real trail riding, as a beginner I would definitely go with a four stroke. The XR's and DRZ's are dirt couches, very comfortable, easy to ride, adequate power and bullet proof but not the best suspension in the world and a bit on the heavy side. The WR's and KTM EXE, KLX and the CRF X Are all woods weapons and are the best bikes you can get for trail riding, a bit more demanding as far as maintenance but they can be plated easily. They have a plush suspension, very forgiving in the woods but too soft for serious track riding.
The YZ F's, CRF's, RM Z's, KX F's and KTM SX are race bikes that totally rip, they have peaky motors, very light weight, no E start, and a board for a seat. The suspension is designed to take bigger hits from jumps. They take a little practice to ride on trails but they will wheelie all day long!

There are some enduro 2 strokes that do extremely well, but for trail riding I wouldn't recommend an MX 2 smoke to start with, but if you will mainly be on a track I think it would be a good option. They are fun as hell but they do require premixing oil and gas.

Bueller
Mon Aug 7th, 2006, 06:23 PM
http://www.sphaera.co.uk/two-stroke.htm

R1chie
Mon Aug 7th, 2006, 06:35 PM
With the latest technology of the 4 stroke the lines have blurred but here are some basic differences
2 stroke: Advantage
Lighter weight
Easier to work on. Top end replacement can be done by about anyone with a tool box. (and half a brain)
Less expensive, because they are not the latest technology, used 2 stroke bike the are cheap by comparison.
Powerful, (almost too powerful) same power for half the CC displacement.
Easier to kick start (especially when hot)
Less maintenance. (does not need oil change every few rides) (no valves to adjust)
More fun (subjective but because of the abrupt power band they are considered more fun to ride but some 4 strokes have similar traits)
Not as finicky to poor fuel, jetting, heat, altitude changes
Runs cooler (you will not develop an instant 3rd degree burn touching the expansion chamber)
Even with years of neglect 2 strokes seem to start.

2 Stroke disadvantage:
You must premix oil with gas (although some have oil injectors you still must fill the reservoir)
2 smokes, often called this because they burn oil and are dirty. (they are illegal for trail riding in California, you cannot get a park sticker for them)
Are more likely to foul spark plugs (but I am finding with 4 strokes if they are not jetted correctly, they can foul plugs as well)
Harder to ride on larger displacement and motocross models, more throttle control is required.

4 stroke advantage:
Runs on pump gas. (great just to drive up to filling station and pump it)
Very durable long lasting motors.
Latest versions are as light as 2 strokes
Smoother powerband, easier to ride. Lots of torque. Not as much power (unless you get the latest models)
Good beginner bikes, easier to ride (latest motocross models are the exceptions)

4 Stroke disadvantage
Harder to start, especially when hot (new models com with electric start but that means more weight).
Pipe super heats, instant 3rd degree burns if you touch it or it lands on you after a wreck.
Generally heavier, often much heavier (latest motocross versions are the exceptions.
Harder to work on. I would not attempt top end job and to have this done at a motorcycle shop is very expensive.
You must change oil or engine will blow up. (The new Honda CRF250 and 450 with seperate moto oil and transmission oil means the motor oil is less than 400cc. It states you must change after every ride or two. A number of these engines have blown up due to neglect and changing the transmission oil only and not the seperate motor oil)

Having said all that, which one to get depends on how much money you want to spend, do you want used or new, what level of riding skills, what is your purpose (riding trails or riding the motorcross track), type of terrain (mountains, desert, tight technical trails, dirt roads that require a license plate) etc.

Once you determine which and what type of dirt riding, skill level, ride or race, night riding, age/physical dimensions, you can choose a bike. If you answer those questions then suggestions on type of bike can be made.

R1chie
Mon Aug 7th, 2006, 07:04 PM
Ok...pardon my ignorance. I am interested in dirt riding but know nothing about it. What is all this talk of 2-stroke vs 4-stroke? I was told I want a 4-stroke but I would like to know why. Also, I know nothing about trail riding. All I have seen are the courses on I-25 up north and east of E-470 on Jewell. Do people take trail bikes to the courses? Like chadincolo said...would I want an MX bike instead of a trail bike if I wanted to do both?

It really depends on what you want to do most. There is no bike that does everything well and will always be a compromise (well the Kx500 and Cr500 could be motocross raced competitively, ridden enduro and desert competitively in expert hands only, have wide ratio, with horse power at bottom and top, but have broken more bones and cause more riders to quit dirt bikes than any bike made.. don't get one)

You can have fun on the motocross track with a WR450 and it is a great trail bike it has lights, has a electric starter great for after you fall down a couple times and are tired, you can make it street legal, very versatile and forgiving compared to a motocrosser, but if you intend to race, even at the novice level, get a YZ450/250. They are much lighter but harder to start. They can be ridden on the trail but require more experience. You must have previous experience fanning clutch or you will stall, since it has no starter and is harder to start, you can get frustrated after stalling it on tricky hills and having to start it.

My suggestion is if you are new to dirtbikes, get the WR, you will ride more with less effort with great fun factor. Even if you have some experience the WR is a great bike (So are the equivalent Honda and KTMs.. Suzuki and Kawasaki do not have bikes in this class)

If you are going to race motocross then buy the YZ. After racing, you will have most of the skills to deal with a motocross bike on the trails. You will spend a good $1500+ for flywheel weight, electrical system/lights, spark arrester, big tank, skid plate to make this bike trail worthy. So if you are not going to race and only hit the motocross track on rare occasions then the WR is for you.

There are other bikes to consider, but these and the Honda CRF's and KTMs (though not for motocross K.T.M= Kan't Take Motocross) are the cream of the crop.

Marauder
Mon Aug 7th, 2006, 07:40 PM
Richie...informative and entertaining as always. I really appreciate the time and effort you put into your posts. My g/f's brother was talking to me about a 2003 YZ250F for about $2000, one of the guys at his work is selling. I agree with your conclusion...I think trail and an occassional track may be the direction I am heading. Not to get on a tangent but this whole thing started looking for a 250 for Jenene. Found an old 1972 XL 250 Enduro like my father had when we lived in Hawaii. Started me thinking about dirt riding. Then Jenene's brother starting talking about his 2 stroke YZ and the rest is history. Plenty of WRs on Craig's list. You really have to change the oil every ride or two? Any late model WRs I should stay away from? I was thinking 2000 or newer. Also, is a WR450 too much for a newbie?

Mel
Tue Aug 8th, 2006, 09:26 AM
Depends...when you say newbie are you talking about yourself or Jenene? If you are talking about yourself, I think you would be fine on a 450, especially with your size...I bet you would do alright on a 250 to start, but I suspect you would be wanting a 450 very quickly.

R1chie
Tue Aug 8th, 2006, 10:23 AM
Richie...informative and entertaining as always. I really appreciate the time and effort you put into your posts. My g/f's brother was talking to me about a 2003 YZ250F for about $2000, one of the guys at his work is selling. I agree with your conclusion...I think trail and an occassional track may be the direction I am heading. Not to get on a tangent but this whole thing started looking for a 250 for Jenene. Found an old 1972 XL 250 Enduro like my father had when we lived in Hawaii. Started me thinking about dirt riding. Then Jenene's brother starting talking about his 2 stroke YZ and the rest is history. Plenty of WRs on Craig's list. You really have to change the oil every ride or two? Any late model WRs I should stay away from? I was thinking 2000 or newer. Also, is a WR450 too much for a newbie?

The Yamahas do not have the separate oil sumps so the total sump for the oil is over 1000cc. I don't change my oil in my YZ for about 5 or 6 rides. Trail riding is easier on the motor unless you are clutching it all the time. Motocross I change it more often but realize that experts (which I am not) running the engine near its potential will have to change it more often. I have heard of more people grenading the engine on the Hondas for oil change abuse, not so much on the Yamahas. Oil change and oil are subjective and you will get 100 different answers, but the more often you change your oil the better. The Yamaha recommendation for the WR is 620 miles. If you ride hard, I would change it more often.

If I remember right, you are a bigger guy. I would get the WR450. The power is smooth, I think it is easier to ride in the woods because of the low end power. I learned on a 250 two stroke knowing as a 15 year old kid, the bike was very powerful and that I should have started with a smaller bike. But I was told the bigger bikes lasted longer and that is what I wanted. So if at 15 my first bike was a 250 enduro at 16 a 250 mxer, I would say you would have no problem with a WR450. I would say the wr 4 stroke is easier to ride than my old 2 stroke.

The 450 will outlast the 250, it will be easier to ride in the slow stuff (bigger guys can handle the extra weight of bigger bikes).

I know 2 guys here at work that bought brand new WR250s. They both were smaller guys which is the reason they chose the smaller bike, one was 5'8. BOTH gave the 250 to their sons and bought WR450s after the first year of owning the 250. The reason was they wanted more power. One of them I told should buy the 450 for the reasons I am telling you. He still bought the 250, he later came back and told me I was right and wished he would have listened. The 250 4 strokes run at higher rpm, they are tuned more aggressively for more top power thus they wear out sooner and they suffer on the low end horsepower needed to haul bigger guys around. They are outgrown leaving the owner with a desire for more power. Altitude up in the mountains of Colorado make them even less effective. 450s are more fun. This may not be true for a wifes bike who would be more than satisfied with a 250 (perhaps still too much bike for most wives) but it seems true for teenage boys, young men and aging adults males who once feel comfortable with the power of a 250 will want to move up.
I hope this info helps but realize it is only my opinion.

R1chie
Tue Aug 8th, 2006, 10:24 AM
Depends...when you say newbie are you talking about yourself or Jenene? If you are talking about yourself, I think you would be fine on a 450, especially with your size...I bet you would do alright on a 250 to start, but I suspect you would be wanting a 450 very quickly.

You beat me to it and said it in less than 60 words :)

Kim-n-Dean
Tue Aug 8th, 2006, 11:04 AM
Marauder - I ride a 2006 WR450 and Kim has a WR250. We go out every weekend and you're welcome to come hang and try them out. However, I can save you some time and tell you to just go get the WR450.:lol:

I grew up on two-strokes and don't think I'll ever go back. Although, I wouldn't mind having my CR500 again. Just for the fact that everytime I let somone ride it, they came back white as a ghost and bleeding...

I know Cheyenne Yamaha will make you a screamin' deal and there's no tax. If you're going to go street legal, get it here since you'll get hit with the taxes when you go to register it. Vickery was doing the 450's for $1,000 under MSRP. I don't know if it's still going on but, they should work a deal. They matched Cheyenne's price when we bought ours.

R1chie
Tue Aug 8th, 2006, 01:08 PM
Marauder - I ride a 2006 WR450 and Kim has a WR250. We go out every weekend and you're welcome to come hang and try them out. However, I can save you some time and tell you to just go get the WR450.:lol:


And if Dean could ride one, anyone could. :) J/K He is a pretty good rider and knows what he is talking about regarding the WR.

Marauder
Tue Aug 8th, 2006, 02:30 PM
Great info, guys...thanks. Got a little more info from Jenene's brother. Yes, Mel, this is for me and not Jenene. Richie, if you consider almost 6'2" and 235 lbs big, than yes. Brian (Jenene's brother) had some interesting comments last night. He was telling me about the actual difference between the "burn cycle" of a 2-stroke vs a 4-stroke. And that a 450 4-stroke is as powerful as a 250 2-stroke. Likewise, similar power between a 250F (4-stroke) and a 125 2-stroke. It was more complex than that, but I got the jist or it. He, too, said that the field is moving towards the 4-stroke and that I would be happier with it. Still undecided on the type. Brian's opinion was that I would be happier with the YZ, slightly modded to ride on trails than I would taking the WR on the track. He honestly thinks that his buddy is practically giving away the 2002 YZ 250F for a great deal and I should take it. I think you have a point, Richie, that I don't want the 250 because I will want more power once I really get into it. Dean, when you say "go out", do you mean trails or the track? Just want to know where you're running your WRs.

Kim-n-Dean
Tue Aug 8th, 2006, 04:29 PM
Dean, when you say "go out", do you mean trails or the track? Just want to know where you're running your WRs.

No track. All trail. We go everywhere in the mountains.

R1chie
Tue Aug 8th, 2006, 05:41 PM
Brian's opinion was that I would be happier with the YZ, slightly modded to ride on trails than I would taking the WR on the track. He honestly thinks that his buddy is practically giving away the 2002 YZ 250F for a great deal and I should take it.

Like I said, no bike can really do both. There have been many internet debates on which crosses over to the other side better. Motocrossers think that a Yz modded for trail is best, I agree but it is also up to 1500 buck more to do it right and not necessary for some who will be mostly on the track.

For someone like Bueller (if I can speak for him) or myself the YZ is a better choice, we understand the limitations (no lighting or electric starter, harder to ride on slow gnarly trails) and can live with them. My hope is to have both so my YZ does not have to ride trails.

The "WR" in WR450 stands for Wide Ratio transmission. It is a 5 speed (the YZ only has 4 gears) The WR will climb slow rocky ledges in Moab in first gear and take you down a fire road at a good comfortable clip. The YZ will never be able to do this without mucho expense and if geared for the hard slow stuff will be wringing out like an R6 stuck in first gear on a race track. (changing the transmission, only possible on later models). Larger tank, skid plate, spark arrestor, flywheel weight (a must in my opinion for a newer dirt rider), are all needed to ride in the mountains.

The weight and soft suspension of the WR as soon as you get on a motocross track and hit the whoops or come up short on a jump. It will not be very competitive in a race.

One piece of advise if you go with the YZ. Do not buy a bike that has been raced by a "B" or Pro (A) motocross rider. They use up the engine and stress/crack the frame in one year. Often you will see them for a low price, new plastic, looks good but often the frame shows stress crack (that will break just because of vibration even if you don't ride it hard) that after welding will only crack again. The motors crank will be used up and many pro riders ride the rev limiter like the motor will never blow.

If you buy from someone who never raced, check to make sure the air filter is oiled. See if you can see if dirt has been sucked through, this could cause early engine failure. Smell the oil and see if it smells burnt.

Good luck, hope you find a good bike, who knows we may see you up at Rampart.

Marauder
Tue Aug 8th, 2006, 05:55 PM
Good advice...I didn't ask if the guy raced it. Brian has him down to $1800. Now I am getting concerned about what you were talking about. I thought you had a good point about the 450, Richie. I had my 600 for a year before I bought the 929 and then, eventually, the 954. Brian is a service tech and has been riding for eons...I don't think he would try to sell me his friend's bike if it had serious mechanical or frame problems. Also, he said the bike was piped and jetted at Vickery by a guy he knows. That the great thing about mechanics...they have connections EVERYWHERE!!

R1chie
Tue Aug 8th, 2006, 06:13 PM
Good advice...I didn't ask if the guy raced it. Brian has him down to $1800. Now I am getting concerned about what you were talking about. I thought you had a good point about the 450, Richie. I had my 600 for a year before I bought the 929 and then, eventually, the 954. Brian is a service tech and has been riding for eons...I don't think he would try to sell me his friend's bike if it had serious mechanical or frame problems. Also, he said the bike was piped and jetted at Vickery by a guy he knows. That the great thing about mechanics...they have connections EVERYWHERE!!

$1800 is a great price and may be hard to pass up, have a mechanic check the frame for welds and flaking paint around the head and stressed members of the frame and engine compression if you want to get it.