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CBR 250 or 200 at 7000 ft?

3K views 10 replies 6 participants last post by  Pete 
#1 ·
So I just moved from CA to AZ and sold my 2010 250 mostly due to the hassle and expense of moving it. Was planning on replacing it here, likely with a 300. Some folks are trying to talk me into a Yamaha Y3. Any ideas? They said at 7000 ft I would need more power but doesn't electronic fuel injection account for thinner air?
 
#2 · (Edited)
Power to do what? Can you describe your riding needs? 7,000 feet; are you in Flagstaff?

I use a 223 cc bike for some things, but have not crossed any high ranges on it; I'm old and I don't play that hard in the dirt any more.

I think that the 400cc twins are just about a perfect town and country street bike, but I needed enduro ergonomics so bought a 471 cc twin road bike that has those ergos. It makes 400-450 mile days enjoyable even for someone in their mid 70s. It easily handles passes in the 10500 foot range.

I rode my old carbureted NX250 up to Flagstaff several times to visit my son. It had no problems climbing up to get on the plateau.
 
#6 ·
I always rode through Strawberry, and sometimes ate there. I'm a back road person myself. The NX was redlined at 9K and that was 89 mph according to the speedo. A 250 will work, but if Kawi has the naked 400 this fall, you should look at that.

The picture below was taken at Lake Mary Lake on the way into Flagstaff.


 
#4 ·
The R3 is going to be a much different bike from the CBR. You are going to need to spin it a lot higher to get to the power.

Altitude does reduce power (less air = less power) but if you like most everything about the CBR250R the CBR300R would probably feel about the same given the altitude change. Most likely it would still feel stronger than the 250 did.

I'd personally go for a Ninja 300 or 400 over the R3, but the CBR is still going to be stronger down low - if that's what you like.
 
#5 · (Edited)
EFI does correct the air/fuel mixture for altitude changes, however there is a net loss of horse power on any IC engine, whether it has EFI or it's carbureted, as altitude increases. It's about a 2.5% HP loss for every 1000 ft. above sea level, and that's after the EFI has adjusted the air/fuel ratio (or in the case of a carbureted engine, after it's been re-jetted).

On my CBR250R I changed out the 14T front sprocket to a 13T, which improves overall performance at high altitude (FWIW, I live at 9000 ft. ASL). The 13T sprocket makes 3rd and 4th gear much more responsive when going uphill on mountain switchback roads.
 
#9 · (Edited)
EFI WILL account for thinner air, but it will do so by pulling fuel. It will run fine, but will be down on power.



Before you listen to anything other people say, try it out for yourself! On a trip to Montana, I got to ride a grom at about 4800 feet, and it was pretty slow, but I could still hit about 57-59 mph without a drafting buddy, up to 66 mph in a superman tuck while drafting the WRX in front of me. It was plenty at 45 mph or less, but above that it felt pretty dead. I also didn't have the pleasure of needing to climb any hills, so it worked out fine for me.





Earlier in that trip I took my V6 accord up chief joseph highway which is about 8000 feet and the power loss was very clear. On my OBD2 reader I have a engine load gauge which uses pressure in the intake manifold to determine percent load. Down in Georgia I can get it up to 96% at full throttle. Up on chief joseph it would only go as high as 83%. That road was an absolute blast though, sharp 180 degree corners, steep climbs, PASSING ZONES!!! I spent a whole lot of time above 5000 RPM there. :grin2: I can only imagine how much fun it would be on a motorcycle, one with enough power that is, not a grom. :eek:
 

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#10 ·
I would not discourage anyone from buying a CBR300R if you can get a great deal on one (and you should be able to). I used to own a CBR250R myself and I still ride my wife's old CBR250R when we ride together (I have larger bikes for longer rides now). If you are seriously considering an R3 I would strongly encourage you to also look at the Ninja 400, it makes substantially more power, has better suspension, and better tires out of the box at a very similar price point (this is what my wife rides now). With that being said any of the bikes in this class will do just fine at that elevation although as previously mentioned they will be a bit down on power.
 
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