moab trip in late july

[Michael Schaefer]

Hi all, My KLR is setup perfect for this flatlander country here in Dallas. But I'm gonna be up in Colorado in a week riding the high passes up there. My altitude will vary from 5,800 to 13,100 along the route. I'm wondering if anyone has any tips for setting the bike up for this kind of riding. Specifically, I'm wondering about carb setup. I'm using the stock carb with stock needles. My pilot screw is currently turned about 1 and a half turns out. Thanks in advance for the info, Michael

[daylan]

Tips for High Altitue Riding.... Don't fall down Cheers

[Fireman Ed]

> Tips for High Altitue Riding.... > > Don't fall down >

I second that one, and watch out for turkeys in the fog. the crash hurts just as bad at 6,000 feet as it does at sea level. Fireman Ed A17---still crooked

[pete88chester]

What you are going to find is that your bike will be running richer at the higher altitudes of Colorado compared to Dallas. This is because the higher you go in altitude the less dense is the air. This is because air has weight & the air at lower altitudes l is compressed by the weight of the air above it. The less dense high altitude air will have fewer molecules of nitrogen, oxygen, co2, etc. per volume than the more dense air at lower altitudes. The thing is that carbs do not compensate for the less dense volume of air flowing through them (there were some, there was a Solex carb used on some Merc. Benz cars that had a main jet altitude compensation), they basically meter out the same amount of fuel per volume at high altitudes as at lower altitudes. So a carb jetted correctly for sea level that is run at higher altitude will mix the same amount of gas to the less dense air which gives you a rich mixture, same amount of gas for less oxygen to combined with. I remember the first time I drove my Pinto to the top of a high mountain & it idled like the choke was stuck on & had low power. The opposite happened when I drove to considerable lower altitude, the engine felt stronger (which indicated it wasn't jetted right for the altitude I lived at). The problem for somebody that lives at a very high altitude that re-jets their carb for that altitude & then goes to sea level, the carb is extremely lean. If they run the vehicle at high speed using high power they could cause engine damage like piston seizing or burning a hole in the piston. Any way back to your question: I do not think you will have much trouble. My A16 has the stock jetting & I have run it at altitudes of 3000 ft. to 10500 ft. with no real problems. Re-jetting it when you get out here may help, but would it be worth it? Considering how lean Kawi sets the carbs to meet air pollution standards it may actually be running better at some higher altitudes. Another thing to consider is temperature. The colder you go the richer the mixture may need to be. A carb jetted correctly for say 5000 ft. & temperatures in the high 90's may not need re-jetting when run at 8000 ft. & temperatures of mid 70's. I found this when taking my road race bike from the Denver area tracks to the race we used to have at Steamboat Springs, CO in the fall. This brings me to another point I have been meaning to comment on. The flat statement that the idle mixture screw should be set to 2 turns out. That may be true for a bike operated at sea level, but may not apply at higher elevations. You need to adjust the mixture screw to get the best idle & transfer to the needle part of the throttle position for your bike according to where you live. Well I was long winded again, sorry. Pete Chester A16

[Michael Schaefer]

Good info Pete. That's along the lines of what I was looking for. So the bike is gonna run rich. So if I need to lean it out a bit, do I close (clockwise turns) the pilot screw or open (counterclockwise) it? I'm looking for an explanation of what that little pilot screw is doing in there so I can figure this stuff out on my own next time. Thanks, Michael --- In DSN_klr650@yahoogroups.com, "pete88chester" wrote: [snip]

> This brings me to another point I have been meaning to comment on. > The flat statement that the idle mixture screw should be set to 2 > turns out. That may be true for a bike operated at sea level, but > may not apply at higher elevations. You need to adjust the mixture > screw to get the best idle & transfer to the needle part of the > throttle position for your bike according to where you live. > > Well I was long winded again, sorry. Pete Chester A16

[Judson D. Jones]

Leave your carb alone. The vacuum slide carb on your KLR will pretty well compensate for the altitude at everything but an idle (just like the Solex that Pete Chester mentioned). Your idle mixture is already set fairly lean. You will notice some power loss due to the reduced air density at altitude, but your mixture will be OK. --- In DSN_klr650@yahoogroups.com, "Michael Schaefer" wrote:

> Good info Pete. That's along the lines of what I was looking for.

So

> the bike is gonna run rich. So if I need to lean it out a bit, do I > close (clockwise turns) the pilot screw or open (counterclockwise)

it?

> > I'm looking for an explanation of what that little pilot screw is > doing in there so I can figure this stuff out on my own next time. > > Thanks, > > Michael > > --- In DSN_klr650@yahoogroups.com, "pete88chester" > wrote: > [snip] > > This brings me to another point I have been meaning to comment

on.

> > The flat statement that the idle mixture screw should be set to 2 > > turns out. That may be true for a bike operated at sea level,

but

> > may not apply at higher elevations. You need to adjust the

mixture

> > screw to get the best idle & transfer to the needle part of the > > throttle position for your bike according to where you live. > > > > Well I was long winded again, sorry. Pete Chester A16

[Arden Kysely]

I'll second Jud's post. I was up over 10,000 feet in Utah last June and the bike ran fine. You may find you don't need to choke it as much (if at all) to start it, since it will already be running rich. __Arden --- In DSN_klr650@yahoogroups.com, "Judson D. Jones" wrote:

> Leave your carb alone. The vacuum slide carb on your KLR will

pretty

> well compensate for the altitude at everything but an idle (just

like

> the Solex that Pete Chester mentioned). Your idle mixture is

already

> set fairly lean. You will notice some power loss due to the reduced > air density at altitude, but your mixture will be OK. > > --- In DSN_klr650@yahoogroups.com, "Michael Schaefer" > wrote: > > Good info Pete. That's along the lines of what I was looking for. > So > > the bike is gonna run rich. So if I need to lean it out a bit, do

I

> > close (clockwise turns) the pilot screw or open

(counterclockwise)

> it? > > > > I'm looking for an explanation of what that little pilot screw is > > doing in there so I can figure this stuff out on my own next time. > > > > Thanks, > > > > Michael > > > > --- In DSN_klr650@yahoogroups.com, "pete88chester"

> > wrote: > > [snip] > > > This brings me to another point I have been meaning to comment > on. > > > The flat statement that the idle mixture screw should be set to

2

> > > turns out. That may be true for a bike operated at sea level, > but > > > may not apply at higher elevations. You need to adjust the > mixture > > > screw to get the best idle & transfer to the needle part of the > > > throttle position for your bike according to where you live. > > > > > > Well I was long winded again, sorry. Pete Chester A16

[kdxkawboy@aol.com]

In a message dated 2003-07-16 10:55:26 AM Pacific Daylight Time, strathound@... writes:

> > My KLR is setup perfect for this flatlander country here in Dallas. > But I'm gonna be up in Colorado in a week riding the high passes up > there. My altitude will vary from 5,800 to 13,100 along the route. > I'm wondering if anyone has any tips for setting the bike up for this > kind of riding. Specifically, I'm wondering about carb setup. I'm > using the stock carb with stock needles. My pilot screw is currently > turned about 1 and a half turns out. > > Thanks in advance for the info, > >

The KLR parts fiche calls out the high altitude jetting for the KLR. According to the shop manual you should run this jetting if you are above 3000'. I live at 4700' valley and do most of my riding between 6000' and 10,000'. I am running the Dynojet kit. They call out a 136 (their sizing not Kehin's) as the equivalent for Kawasaki's high altitude setting. For my riding I've found the bike runs best at those altitudes dripping the main jet another size and putting the needle jet clip on the 4th or 5th notch from the top - I can tell the right setting because it stops the muffler backfire 'poof' I get only when turning the engine off. There is something else to cover that don't deal with the bike. It doesn't sound like you are used to spending time at high altitudes. Do not be surprised if you start feeling light headed, or a bit dizzy. Its just your body reacting to the O2 being thinner. Common name for it is altitude sickness. From a pure biomechanics POV, you autonomous nervous system has to learn to tell your lungs to take deeper breaths to draw in enough volume to satisfy your oxygen needs. Its one of those quirky things that defy any means of predicting who, or when it will hit. All that can be said is it can happen to folks as they get above 6000'. Pat G'ville, Nv [Non-text portions of this message have been removed]

[Randy.Hoskins@worldnet.att.net]

Michael, Don't worry about messing with the carb. Stock KLR's have been riden to over 17,300 ft (been there, done that) without messing with the carbs. There is some loss of power, but as noted by some of the other listers your body is losing a lot more than the bike. I once did a head to head race with another KLR at approximately 15,000 ft. His bike had been setup for high altitude operation. He had drilled his air box and changed his jetting. My KLR was pure stock. My top speed was 75 mph. He could do 85 mph. From a practical standpoint however, it didn't make much difference. There aren't that many places in Tibet where you can ride 85 mph. Under normal trail riding, I had plenty of power. It is also important to note, however, that after we dropped from the last 17,000 ft pass to lower elevations, his bike was hardly running (top speed 25 mph) until he rejetted his bike. Mine was still running strong. Randy A13 Michael Schaefer wrote:

> > Hi all, > > My KLR is setup perfect for this flatlander country here in Dallas. > But I'm gonna be up in Colorado in a week riding the high passes up > there. My altitude will vary from 5,800 to 13,100 along the route. > I'm wondering if anyone has any tips for setting the bike up for this > kind of riding. Specifically, I'm wondering about carb setup. I'm > using the stock carb with stock needles. My pilot screw is currently > turned about 1 and a half turns out. > > Thanks in advance for the info, > >

[Mark Sampson]

I agree------to do absolutely nothing to your KLR to ride high altitudes. It will do fine----the idle will drop and the power will drop----but it will do fine. And when you come back down-----you can do nothing again, as it will run fine !!!! I've stood and watched guys diddle with jetting several times on the road and trail while I just stood and watched. Have a clean air filter tho. Mark Sampson www.bigdogadventures.com