Power Loss at Altitude
Posted: 01 April 2008 08:06 AM   [ Ignore ]  
Legend
RankRankRank
Total Posts:  230
Joined  2008-03-03
Has anyone ever put any numbers on the amount of power lost at higher altitudes? I know it is significant, just wondering if there is any formula or figures.

I bought a new 1098 last spring and broke it in at 6500-7000 feet. Seemed to be fast enough, but when I took it to Laguna Seca in July and rode it around at sea level it was noticably quicker. Free horsepower!
Profile
 
 
Posted: 06 April 2008 05:35 PM   [ Ignore ]   [ # 1 ]  
Abnormal User
Avatar
RankRankRankRankRankRank
Total Posts:  1951
Joined 
At Bonneville(4400ft. or thereabouts) they say the power loss is 10% compared to El Mirage(2500ft. or thereabouts). Your obvious answer is to move to Laguna Seca.LOL!
 Signature 

Speak to me, I’m your friend.  Race with me, I’m your brother.

Profile
 
 
Posted: 09 April 2008 02:44 PM   [ Ignore ]   [ # 2 ]  
Legend
RankRankRank
Total Posts:  230
Joined  2008-03-03
I have a better solution in my dreams - just go get the 1098R and be done with it...

Wouldn't mind living close to Laguna Seca, though. Perhaps I can start a new career picking lettuce or catching fish or being a guide at the Steinbeck museum. Or better yet, be a pro Superbike rider.
Profile
 
 
Posted: 26 May 2008 10:42 AM   [ Ignore ]   [ # 3 ]  
Legend
RankRankRank
Total Posts:  271
Joined 
DARBY - 01 April 2008 08:06 AM
Has anyone ever put any numbers on the amount of power lost at higher altitudes? I know it is significant, just wondering if there is any formula or figures.

I bought a new 1098 last spring and broke it in at 6500-7000 feet. Seemed to be fast enough, but when I took it to Laguna Seca in July and rode it around at sea level it was noticably quicker. Free horsepower!


Air density and hence power decrease by about 3% for every 1,000 ft of altitude (assuming constant temperature) so at 7,000 ft asl you would be down around 21% on power. In terms of flat out speed it may not make too much difference as there would be a similar reduction in air resistance it would just take longer to get to the max. speed.
Profile
 
 
Posted: 27 May 2008 01:14 PM   [ Ignore ]   [ # 4 ]  
Abnormal User
Avatar
RankRankRankRankRankRank
Total Posts:  2032
Joined 
This page here has all the info you need to get all the information you need. If you know your exact altitude you can calculate everything else.

http://wahiduddin.net/calc/density_altitude.htm
 Signature 

It will bring you so close to nausea, it will make you sick! - Big Al

Profile
 
 
Posted: 28 May 2008 04:52 AM   [ Ignore ]   [ # 5 ]  
Legend
RankRankRank
Total Posts:  271
Joined 
r60man - 27 May 2008 01:14 PM
This page here has all the info you need to get all the information you need. If you know your exact altitude you can calculate everything else.

http://wahiduddin.net/calc/density_altitude.htm


I was just giving an approximation as few riders know either the dew point or the altimeter setting at a given time or location.
Profile
 
 
Posted: 29 May 2008 07:34 AM   [ Ignore ]   [ # 6 ]  
Abnormal User
Avatar
RankRankRankRankRankRank
Total Posts:  2032
Joined 
heritage32 - 28 May 2008 04:52 AM
r60man - 27 May 2008 01:14 PM
This page here has all the info you need to get all the information you need. If you know your exact altitude you can calculate everything else.

http://wahiduddin.net/calc/density_altitude.htm


I was just giving an approximation as few riders know either the dew point or the altimeter setting at a given time or location.


No problem, but this will allow people to dig a little deeper into the issue. Bike set up is tricky depending on where you live. Here I only range between sea level and about 1800 ft. above, so I really do not get into feeling a problem. However, if I go to the mountains I know it.
 Signature 

It will bring you so close to nausea, it will make you sick! - Big Al

Profile