Getting back into Dirt Riding. A few Questions on 250's & 500's

[pjb84]

Hey everyone, its been about 4 yrs since I've owned a dirtbike of any kind. I've been riding sportbikes since then and I currently own an R1 (which is for sale). I've been riding some kind of bike since I was 11 yrs old and I'm a pretty experienced rider but have become out of touch with the dirtbike world and I'm hoping you can all answer a few questions I have:

1. I want to get a 2 stroke so I can feel like a kid again. :laugh: How often do these need to be rebuilt and how much does it cost? Can someone who is pretty mechanically inclined do the job at home?

2. Should I sway away from a late 80's CR500 or KX500? How often will these need to be rebuild also? I'm looking at an 88 CR500 which has just been rebuilt.

3. Why do these bikes need to be rebuilt so often? I owned a KDX 220R for 4 yrs and never had to rebuild it and never had ANY problems. It started 1st or 2nd kick everytime.

Thanks guys!

 

[Moparman1539]

Well... i think they say every 15 hours or so. But every year would be a good time to do it. If your not really hard on the bike you could probably go 2 years... And for me it would cost about $200+/- for a new piston and rings and for the cylinder to be honed or bored. It is a pretty easy job to replace the top end. (piston and rings) (have your shop hone/bore/or re-plate the cylinder.) Order the parts and put it on. I did the top end on my Ke100 when i was 15 :cool:. had a little bit of help.

I have a 1983 KX250, and so far its been pretty reliable. Its kinda lacking down low, but has a wicked powerband. The only downfall i really have with the bike is it is hard to find parts for. So try to find the NEWEST bike in your price range and you should be fine. But the older they get the harder they are to find parts for. And Usually the bigger the bore the longer they will last between rebuilds. But don't quote me on that.

And i'm not really positive why they have to be rebuilt so many times but i think its because they are high performance engines. And the parts just wear out quickly. And a KDX is still a 2-stroke. I'm sure it was due for a good rebuild. But if you don't punish the bike it should last a while.

Good luck, And have fun!

 

[rossim22]

It depends what you mean by "rebuilt" engine. If it's just top end, it's pretty much a maintenance thing. If it's bottom end, clutch, valves... then it's probably just because the bikes you're looking at are 20+ yrs old.

 

[_JOE_]

What exactly do you plan to do with the bike?

 

[FNG]

I am wondering the same thing.

I just bought my first true dirtbike at the ripe old age of 38. As a kid I rode mini bikes and then a DT 100 before jumping into the 3 wheeler/4 wheeler/snowmobiling world and left dirtbikes behind.

I decided 1000$ was my budget so I went shopping for a 250. I am 6'4" and 225# so I knew a 125 wasn't gonna do it for me. In the past I have ridden a few dirtbikes and even spent a day on a real dirtbike track. I got to ride a 95'YZ 125 and a 97'RM 250 that day. I also threw my leg over a 93' I think KX 500 and HOLY CHIT!! What an ANIMAL!!!!

I settled on a 95' YZ 250 for 700$ and spent another 350$ getting it right and it has been a blast all summer! Plenty of power, actually more than I can use on the track, but better to have too much than not enough.

As for rebuilds, my top end will be replaced over the winter. I still have 180# of compression and when I cleaned the power valve and took the head off for an inspection it looked ready for one more season of rookie abuse:)

Like others have said, rebuilds depend more on time on the motor and how hard they are ridden.

 

[d_alexand]

bike choice... depends what you're gonna do with it?

pjb84,
The 500 is definitely the R1 of dirtbikes... if you're gonna just ride trails or desert then it's cool, but if you're gonna put it on a motocross track then it's way more than the average joe can handle. If you must have the 500 then use extreme caution. The kx500's and the older cr500's have a powervalve and are pretty wicked, but the newer onces were tamed a little & had a better chassis. I've ridden a 2001 cr500 and it was truely a bike that demanded respect.

I have similar experience (started on dirt years ago, rode street & roadraced off/on, and switched to mx last year) and a 2-stroke 250 would probably be easier for you to adapt to. The modern 250's are pretty fast so it'd be a step up from the kdx.

 

[stuart500]

Go for the KX500. It will give you a smile.

 

[whenfoxforks-ruled]

For some reason that remark about the 500 needing to be rebuilt after 15 hours, sounds more like a 125 rebuild time? It has to be the longest running engine between top ends! Be more concerned about your safety, and parts like tires and chains. Even a 250 should be in the 20 or so hour mark? Then you throw in the trail riding and you are probably not Brad Lackey, so the rebuild time goes way up. Just check it and you will know where you stand. Them older Cr 500's can be a real bummer starting, technique, and decent mechanical shape helps a ton, speaking of such, if you are over 180 pounds should help allot! Personally, look hard for a KX, they have a power valve, and a much better hit off bottom!

 

[Panhead]

get the 500

I own a 2003 kx 5hunny. You will not need to rebuild all that often unless you do alot of desert riding. Many people rebuild these things because a race bikes rebuild quite often. Only rebuild it if the compression is down. If you are gonna track ride, it is a alot to handle (for me). A lighter higher revving bike will be better on a track.

I'm 5' 9" and weigh 250, and I'm as fast as anthing in the dirt. The 500 bikes demand respect but are awesome, and everyone knows what you ride when they are behind you. I personally like riding what most others are afraid of.

You want to be the man? You gotta ride the man.

You have a R1, you can handle it!

 

[gwcrim]

I'm with Panhead. A 500 two stroke is an awesome bike. They are low revving engines so they need rings less often than a 125 or 250. MUCH less often.

They're great for lazy riders. Put it in 2nd or 3rd and never shift.

Hill climbs? They laugh all the way up.

Deep mud? One good BRAAAAP on the throttle and you'll be the first to the other side.

Hot starting? Nothing like a four stroke. One or two good kicks and off you go.

 

[_JOE_]

Make sure you have good health insurance!!!

 

[whenfoxforks-ruled]

Make sure you have good health insurance!!!

Pffffft! Now Joe, you know that on an mx track and the correct rider, your bike will walk away. Therefore traveling at a higher rate of speed makes your bike more dangerous! AFLAC!

 

[_JOE_]

Pffffft! Now Joe, you know that on an mx track and the correct rider, your bike will walk away. Therefore traveling at a higher rate of speed makes your bike more dangerous! AFLAC!

I guess, if you really twist your perspective, that may be true. I have passed a 500 or 2 on the track. Usually right before or during a corner where they were trying slow down and turn in a nasty heavy pile of high horsepower steel that tried running away on the previous straight. :)

 

[ws6transam]

Just wanted to chime in,
After 18 years of no dirt bike, I jumped in again with a '92 Yamaha WR500. I took it to a MX practice track last Thursday. It was an eye-opening experience. At first, I thought the bike was going to kill me. Then I shifted out of second gear into third gear. That tamed it "just a little". I spent the remaining 16 laps in second/third, just trying to learn how to turn and brake again. Never did I use more than half throttle because even half-throttle was enough to lift the front-end and eliminate all steering input. Jumps? Sneeze once, and close your eyes, and you'll jump. After about thirty minutes of ride time, my arms and legs were jello, and I spent all of Friday, Saturday, and Sunday hobbling around with the sorest muscles I've had in probably sixteen years. In hindsight, I might have been just as happy with a little liquid cooled 250cc YZ.

However, Those last laps were much more comfortable than the first, and by lap sixteen I could even "pilot" that bike without feeling like I was going to die. It was work, but a thrill nonetheless. I didn't die, I didn't crash, but I did get unintentional air, and all I can say is that if you feel like getting a 500, then get one. Just be ultra careful with the fuel: Respect it, and you'll survive. The CR500 and KX500 is supposed to have even more salsa than the simple air-cooled 490cc motor of my WR.

 

[abitiseb]

I got back to dirt bike in 2006 and like you I was previously on road bike 92 gsxr1100 and 03 gsxr1000 and I have to go back in 1989 for my last dirt bike. Right know I own a 01 KDX220r and a 04 KX500. What I can tell is dont be affraid of the KX500 but look at what your going to do with the bike if your gonna do tight stuff the 500 is not really a good idea (it can do the job but not as funny as with the KDX ) but for open stuff go ahead you will smile all the time (well I do!) . That the reason I have both the KDX and the KX and for nothing in the world I would let anyone of them go. By the way my KDX got motor carb and suspension mod and the KX got only a pipe on it. Hope it help you out and have fun.

 

[abitiseb]

I got back to dirt bike in 2006 and like you I was previously on road bike 92 gsxr1100 and 03 gsxr1000 and I have to go back in 1989 for my last dirt bike. Right know I own a 01 KDX220r and a 04 KX500. What I can tell is dont be affraid of the KX500 but look at what your going to do with the bike if your gonna do tight stuff the 500 is not really a good idea (it can do the job but not as funny as with the KDX ) but for open stuff go ahead you will smile all the time (well I do!) . That the reason I have both the KDX and the KX and for nothing in the world I would let anyone of them go. By the way my KDX got motor carb and suspension mod and the KX got only a pipe on it. Hope it help you out and have fun.