Hi all, wondering if anyones had any real issues with DRZ 's' model (no modifications to jetting or airbox) at altitude? We're going to south america in Nov starting Colombia and finishing Argentina going over the hilly bits so probably looking at max 13000ft give or take. I know its going to make them sluggish but hopefully it wont be too much of an issue!! Any advice greatly appreciated
cheers Tim

I don't have a DRZ, so can only report that my unmodified KLR did ok at altitude--wheezy and weak, but always ging onward in whatever direction I pointed it.

You'll go higher than 13,000 ft. unless you're really determined not to. I topped out well over 15,000, and some common rides go much higher.

Mark

In stock trim I'm thinking you should be pretty much OK. Sluggish? yes. Probably over about 10,000 ft. you will feel it ... but it should still run without loading up and fouling plugs.

Two simple things to do to help the motor when very high:

1. I think your carb has a Pilot (air/fuel) mixture screw? Make sure you get an extended screw that is easy to access. This is a very handy thing to have. When you get to very high altitude your idle will drop and be rough. Starting may be hard too. Your fuel economy also will drop sharply the higher you go.

By leaning out the Pilot mixture screw adjuster slightly you can really improve this. Going IN on the screw a turn or two can make a huge difference ... and save fuel as well. The idle will smooth out and bike will start more easily.

2. I think your bike has a snorkel or some sort of air box cover. If things get too sluggish, pull off the Snorkel or air box cover, or both. (temporarily) This will lean out mixture and help the motor get more air at very high altitude. Be sure to replace once down below 7000 ft. or so.

Honestly, since the DRZ-S is a street legal bike with a CV carb, in stock form it will be running quite lean from the factory. Because of this it will do well at high altitude up to 10 to 12,000 ft. and I don't think you would need to re-jet for the highest roads.
The two steps above should help some with idle, starting and fuel economy. No matter how well the bike runs, even re-jetting, it will naturally be down on power up over 10,000ft. All motors loose power at very high altitude ... yes, even Fuel Injected ones.

My girlfriend's in the Andes at the moment, riding a stock DRZ400S with a DEP silencer. She was at 4,400+ metres a few days ago, emailed to say that the bike ran well but lacked power at altitude.

Fuel economy nearer sea level was 70+ mpg, not sure what she's getting at present, I think she's nearer 3,000 metres at the moment (Sucre, Bolivia).

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Cheers for that guys, it was what I was thinking/hoping for. Any ideas where I can get hold of the longer pilot screw in the uk ? (time a bit short now!) I can always make up a stubby flathead if need be tho! What kind of temperatures are you getting down to at 13-15k as wondering if any carb problems?
thanks Tim

In December and January (i.e., mid-summer) I saw nothing too extreme for temps: 0 degrees C with blowing snow was the worst of it, and that was only scattered here and there in squalls. Mostly.

Be aware that there's a big difference between 13,000 feet and 16,000 feet--for the bike, for the weather and for your poor, malnourished self.

enjoy,

Mark

my better half's vegetarianism is a bit of a worry, as I'll eat anything (so long as no-one tells me what it is !!!! sack full of biscuits required me's thinks cheers mate