The "R" in 250R and 450R stands for "Racing".
I don't race and I love my R.

 

if u want to get a true "R" bike,a 1986 honda 250R is the way to go

 

my friend has 1,and i road it and i have to give it to him,its fast.its a good choice for a almost any rider.but if u are new,and just starting off,the 450R is a little much.

 

I use my 450er and I love the thing I wasn't worried about anything I heard and like was said before if it can withstand the baja that is a challange in itself just to finish is hard let alone win first place...the newer model r's have a different look to them with the hood compared to the older ones but mand I couldn't have wished for a better handling and running quad...If you maintain the bike and check the fluid levels and take care of it you should have no problem maintanance wise...and as long as you check over these things along with the valves this bike is unstoppable

 

1989 was my year on the 250R.

 

You mentioned the Z400 earlier. Except for the frame issues on a few 03's, it is a dead solid machine. It hasn't been around as long as the 400EX so it hasn't has as long a time to prove itself, but I would say in the long run it is going to prove to be just as venerable a machine as the EX. It certainly has an engine that is more buildable than the EX.

So what's the point of this post? Are you actually considering a purchase, or just thinking out loud?

 

We have a bone stock 450r in the shop right now for engine work. Broken connecting rod just below the wrist pin, cylinder ruined, cases cracked from front to back, and tranny locked up. Talk about a costly fix w/ no warranty.
It's the only one I have seen like this to date. The only one that has been in our shop for any work after the sell. They do make some noise and to me sound like something is about to fly apart all the time but we don't have any problems out of them.
The 400ex and the 450r are good quads and are reliable. But, they are only as reliable as the person who does the maintenance on them. If you don't change your oil, clean your air filter, keep your chain adjusted and lubed, adjust your valves, check your rear axle nut for looseness, and tighten up some bolts every now and again then don't expect it to have a long life. Most of the 400ex's that I see in the shop are there b/c of dirt. Dirt will get in the engine and ruin your valves, rings, cylinder, piston, bearings, etc. When you start to do mods like removing the airbox lid and running a K&N air filter you are asking for trouble.
P.S: Don't run a K&N air filter on a quad. They flow better, yes. But, they also let in more dirt. A high revving engine like the 450r is really pulling in some air so it will pull in more dirt if allowed which will decrease it's life expectancy.

 

The point is kind of both I guess then...

Considering a purchase and some thinking out loud too.

I dunno... I sorta like talking to the 'masses' too when it comes to stuff like this because you can get more info this way than talking to a couple guys who have them. The only down side is that sometimes you can also come away more confused than before too.

The cool thing that has happened since I posted this is... a bit before posting this, a buddy and I were discussing all the sport quads out now. And I mean all of them. I guess this sorta got his clock ticking. I didn't know it until after we started talking, but both of his machines were trashed and in need of serious repair. So I just found out he went and bought two new quads this week after our talk... LOL...

(note to self... steer clear of his wife for a while)

Anyways, one of the two he ended up buying was a Honda 450R kick.

So hopefully before too long I'll get a chance for us to get together so I can give it a serious ride.

 

Now you can find out first hand what the 450R is like, instead of just stuff that you've "heard".

 

Be sure your friend with the new R knows all about these engines. Have him go through the old posts in here, and he will get lots of information. Things like: break it in hard, frequent oil changes, run at least 100cc's of extra oil in the trans, keep up on the valve adjustments, etc.

I highly recommend a synthetic oil for these machines. I recommend Maxima Extra ester synthetic, in both the engine and transmission sides.