Advice wanted on riding 250cc scooter over the Rockies, specifically: altitude-related power loss?

Question

I will be crossing the Rockies on my way from CA to NY(I've heard all the reasons not to, and I'm going anyway) and wondered how much power I can expect to lose as I rise in altitude. I am concerned about keeping up with the flow of traffic. I won't be on major interstates, by the way. The bike is newish (<3000 miles) and has traveled from SF to LA without missing a beat.

Any constructive advice would be appreciated. I've had a lot of people inform me that I am suicidal, crazy, overly optimistic, etc, but an equal number wish they could come with me!

Thanks in advance. AlbeeC

Answer 1

A million years ago, back in the 1960s and 70s, people used to routinely cross the continent on 250s.  It&#039;s hard to imagine these days when 100 hp is considered the minimum for a motorcycle, but in those days motorcycle magazine writers used to say, often, that there was really no reason a bike had to be bigger than 250cc.

The problem is the roads.  If you ride all day on a freeway, 250cc is just not big enough. The poor little thing will beat its heart out, plus it won&#039;t be either comfortable or safe.  So the trick is to keep to secondary roads--roads with a 45 mph speed limit where people go 60.

I wouldn&#039;t worry about the altitude.  I have crossed high mountain passes on a bike and you really can&#039;t tell.  Especially on a modern bike with fuel injection, there are sensors that detect the air pressure and change the mixture accordingly.

Years ago I crossed the Rockies in a 1969 Volkswagen Camper.  We took Hwy 70 through Grand Junction and  Leadville to Denver.  Leadville is 10,000 feet high, it&#039;s called &#039;The Two Mile High City&#039;.  That day we drove all day long at 30 mph, because it was all the van could do on that grade.  But we made it just fine.  That would be fun on a 250cc bike!  You just need a little patience.  8^)

Good luck!  I wish I was going with you.

Answer 2

Since we don&#039;t know the make/model/year of your scooter, we cannot know if it is fuel injected or carbureted, so I would be willing to bet that a 250cc scooter is carbureted.  Yes, I know there are injected ones out there, Aprilia has been doing 50cc models for almost 10 years.

If it is carbureted, then you will have altitude-related power loss because the ambient air has a lower percentage of oxygen than at sea level.  Just like putting a candle under a jar, the candle goes out as the oxygen is used up.  The engine begins to have a rich condition, which means there is more fuel going into the cylinder than is needed because there is not enough oxygen in the air for complete combustion.  Of course, fuel injected bikes will also suffer an altitude-reladed power loss due to the reduced amount of oxygen in the air, but they don&#039;t suffer the same rich condition because the computer that controls the fuel injection system reduces the amount of fuel going into the engine.

To answer your question:  Yes, you will have altitude-related power loss regardless of your fuel delivery system.

Constructive advice:  Have a basic set of tools, including those needed to perform basic repairs.  A roll-up pouch works well and takes up less space than a shoe.  Have a copy of the service/repair manual for your scooter downloaded onto your Blackberry/Palm/PDA to be able to diagnose and repair things when you&#039;re in the middle of nowhere.  A set of tire plugs and patches, including glue, or a tube of Slime, will help you out in a bind.  A small pump for your tires is available in the bicycle section of any store, it costs the same as the compressed air stuff and you can use it for years instead of only once.  Very helpful if you&#039;ve still got a leak and have to re-air several times on the road.  Be sure you&#039;ve got something reflective on your jacket, think about adding additional lights to the front and rear if you can.  Most of all, be safe.

Answer 3

I dont know the percentag of power-loss, but there WILL be some.See a local dealer, and ask about possibly re-jetting the carb..( Bigger main jet ) .You also asked for advice; Trade it in on a 650, or bigger !

Answer 4

You will loose a little while you are crossing over but it will come right back again. How  big is the scooter?  You should not loose enough to be a traffic hazard.   I would think 250cc and  up would be no problem. When  I was in Denver there were scooters everywhere.

Answer 5

If the bike is fuel injected, shouldn&#039;t be a problem, it will adjust itself.

I doubt really that you have any issues and need to make any adjustments.  The air is thinner...but it is also cooler. There is less oxygen in the air, but you will be getting more air into the cylinders.

I doubt you notice much of anything, good luck on your trip!!!!