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Anyone take their CBR across the Rockies, or another high elevation/steep grade?

I've done it in a Superhawk and noticed a huge drop in power vs sea level, but that was carbureted, so I'm not sure it had all it's power.

I'm probabaly 250-260 in all my gear, and on a hot/muggy day I've seen top speeds as low as 77 or 78 (mph), although it's typically 85+.

I could live with going 55 or 60 up the hills in the thin air, but I don't want to be doing 37mph flat out for an hour trying not to get run over by 18 wheelers, I'm wanting to go to Oregon or California from Chicago as it's been a while, just trying to figure out what's practical.
 

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Ive had mine up to 8415 feet, no noticeable loss of power....ive also had a crbed bike that high and it ran like crap. The Fi system will recalibrate.
 

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Anyone take their CBR across the Rockies, or another high elevation/steep grade?

I've done it in a Superhawk and noticed a huge drop in power vs sea level, but that was carbureted, so I'm not sure it had all it's power.

I'm probabaly 250-260 in all my gear, and on a hot/muggy day I've seen top speeds as low as 77 or 78 (mph), although it's typically 85+.

I could live with going 55 or 60 up the hills in the thin air, but I don't want to be doing 37mph flat out for an hour trying not to get run over by 18 wheelers, I'm wanting to go to Oregon or California from Chicago as it's been a while, just trying to figure out what's practical.
Any non-turbo or non-super charged internal combustion engine, whether carb or EFI, loses about 2.5% of its sea level horsepower for every 1000 ft. of increase in elevation. So, at 10,000 ft ASL your HP is down by about 25%. One of the advantages of EFI is you don't have to make any adjustments as you go up in altitude... a carb engine has to be re-jetted just to stay even with that 2.5% decrease in HP. A carb engine that isn't re-jetted would see a much larger decrease in HP, perhaps as much as 5%.

You'll definitely need to work the gearbox a lot when you get out to the Rocky Mountains, riding up mountain passes with 7-9% grades. I live at 7000 ft. above sea level, and regularly ride roads that take me up to elevations of 10,500 ft. I run a 13T front sprocket on my 250R, which definitely improves high altitude performance.

Don't worry about being run over by an 18 wheeler, they will literally be crawling up and down these mountain passes.
 

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The highest I've been so far is the top of Mt Washington at about 6200'. The bike adapted to the altitude a lot faster than I did - I winded myself pretty good climbing the last 20' or so to the summit.
 

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I currently live in said Rockies. I purchased my bike in Denver and then took I-70 to Avon (just past Vail). I went up and over 2 passes (Loveland (actually the tunnel) and Vail passes). I was usually cruising around 70mph most of the way. Up the passes however I lost some steam. I was never going slower than 55-60mph up either pass. With the small displacement of this bike, you're never going to set any speed records heading up the passes on the highway.

That being said, one of my favorite rides is down 24, from Minturn to Leadville. It takes me over Battle Mountain and Tennessee passes. The bike crushes both. It's not highway speed; you're downshifting and taking plenty of corners.

Passes while on the highway/interstate = mehhh
Passes on normal roads = great!

With a stretch of 75mph highway between some of my regularly traveled exits, I get the bike up to 80mph with little effort. I weigh about 195 without gear (prob 215+ with). The bike does perfectly fine at altitude.
 

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Anyone take their CBR across the Rockies, or another high elevation/steep grade?

I've done it in a Superhawk and noticed a huge drop in power vs sea level, but that was carbureted, so I'm not sure it had all it's power.

I'm probabaly 250-260 in all my gear, and on a hot/muggy day I've seen top speeds as low as 77 or 78 (mph), although it's typically 85+.

I could live with going 55 or 60 up the hills in the thin air, but I don't want to be doing 37mph flat out for an hour trying not to get run over by 18 wheelers, I'm wanting to go to Oregon or California from Chicago as it's been a while, just trying to figure out what's practical.
I went up to ~10,700 feet and gained power!!! :O To be fair i just installed my new exhaust and it was running lean at lower altatue and got the mix right at the higher altatue... But now it just feels like its working a little harder (imanage a car that is overheating and starting to loose power) but its not so bad that I would worry about it
 

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Anyone take their CBR across the Rockies, or another high elevation/steep grade?

I've done it in a Superhawk and noticed a huge drop in power vs sea level, but that was carbureted, so I'm not sure it had all it's power.

I'm probabaly 250-260 in all my gear, and on a hot/muggy day I've seen top speeds as low as 77 or 78 (mph), although it's typically 85+.

I could live with going 55 or 60 up the hills in the thin air, but I don't want to be doing 37mph flat out for an hour trying not to get run over by 18 wheelers, I'm wanting to go to Oregon or California from Chicago as it's been a while, just trying to figure out what's practical.


i took mine all the way to highest possible roads in the world... averaging 15000 feet most of the times and peaked out at 18,500 feet.. no power loss.. beyond 16000 feet in steep inclines when i felt the bike was sluggish.. ( placebo effect) .. disconnected the battery wire.. removed filter cover and reconnected after 20 minutes... ( ECU reset + some extra air flow) and it kept singing just like at sea-level...

cbr went flying into knee deep slush and iced roads and temperature ranging from 40 degree Celsius to -5 degree
 

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