I am looking into getting a 450R or a 400EX. I can't decide between the two machines.

Basically I am looking for something I can toss around on an MX track and ride on trails occassionaly. I won't be racing except for occasional drags against friends.

The reliability of the 400 entices me because it's the old XR motor which is indestructable. I see how my friends' XRs are. However I am concerned it will be too slow from me (coming off of a KFX700).

The speed of the 450 interests me of course. How is the reliablity? I know the new high performance four strokes can be a handful to maintain.

 

I own both. I prefer the EX for riding tight trails, because the engine will lug down. Excellent handling machine, excellent quality, excellent durability. It flies well, but is underpowered for the track.

The R is a superb machine as well. It likes to rev and is geared tall, so it can be a handfull where you need to ride slow, like on a technical trail. Excellent handling on the trail or at high speed, and excellent quality. Flies like a bird! Goes faster than I usually care to go! Reliability??? Nine of the top ten finisher in the last Baja 1000 were R's.......that's all I need to know!

 

For the price difference (about $900), can you make a 400EX run with a 450R? I know it can probably be done but if it would be more than the initial price difference between the two machines it seems like the R would be a no brainer.

 

No! You could not make a 400 run with a 450 for any amount of money. In the modern scheme of things, displacement doesn't mean a thing unless you are comparing engines of identical design (THERE IS A REPLACEMENT FOR DISPLACEMENT!). You could bore a 400 out to 450, and it still wouldn't keep up. The reason? The 400 is air cooled, it's heavier, older lower tech design, etc..............

The upside of the 400 is it will run forever with only minimal maintenance, and if you care for it you may never have to rebuild it. The 450 will require frequent oil changes and valve adjustments, but should easily go 200+ hrs. without a rebuild.

Take a good look at the Z400 as well. It is perhaps the best all-around machine there is. It handles much like the EX, but is faster, and that motor has huge hop-up potential. My Z doesn't fly as will as either my EX or R. It flies kind of front heavy for some reason, so you have to be on your game and really launch it.

 

200 hours would be like 3-4 years with the amount of riding I do. That is probably OK.

Really I would just like to know if the amount of money I would spend up front and on maintenance is worth it. It sounds like it will be even though I'm just a casual weekend rider.

 

The only real expense is oil and filters, which anybody can do themselves. If any motor can benefit from a synthetic oil, it is the 450's. I run rather expensive, ultra high quality ester synthetic oil in everything. http://www.maximausa.com/technical/l...beNews2002.pdf

I don't have the patience to do valves, so I take it to the dealer for that.

 

I have about 2k, into my stroker 440ex. It will on a good day, come kinda close to my 450r. I think my 450r has all the reliability, of a 400ex. Infact its better, I have yet to put a battery in the 04 450r, and the EX is on its third battery.[img]i/expressions/face-icon-small-wink.gif[/img]