DRZ400s jetting for Colorado?

[dualsports]

How would you set up a DRZ400s for Colorado? I'm considering buying a DRZ but I'm worried that I won't be able to ride around town at 5000 feet elevation if my bike is set up for 8-12 thousand foot mountains. Is there a way around this? In other words, how would you jet a DRZ for 5,000-13,000 feet?

[William1]

Cart before the horse. Get a bike, then worry about setting it up.

[ptgarcia]

3 hours ago, William1 said:

Cart before the horse. Get a bike, then worry about setting it up.

Haha, so true.

Generally, though, I'd jet for the altitude you mostly ride at. If it's at the extreme end of your anticipated range, then move it towards the center of the range a little. Don't over think it.

[rustynut2]

I'm at 430 ft, Illinois flat land. JD kit on their recommended settings. Bike runs fine in Colorado, Silverton, Durango, Gunnison and such, a little less power but no issues. Bike is geared down for the hill climbs at 15-47. I road it the first time there with stock gearing, so much better geared down a bit.

[bucket list]

Stock carb. on DRZ does well with big elev. changes.  I go from sea-level to 8,000ft still runs good. But i set it up on the lean side at sea-level.

[SilvFx]

On 11/20/2019 at 12:50 PM, dualsports said:

How would you set up a DRZ400s for Colorado? I'm considering buying a DRZ but I'm worried that I won't be able to ride around town at 5000 feet elevation if my bike is set up for 8-12 thousand foot mountains. Is there a way around this? In other words, how would you jet a DRZ for 5,000-13,000 feet?

dude...you are overthinking this.  As i mentioned on the other thread, I ride my WR450F and KTM 300 XCW without changing the jetting.  Ride in Moab...about 4500 elevation and ride up in the high peaks as high as 12.5-13k ft.   No jetting changes.  If you plan to ride a lot here in Denver, jet for Denver altitude (e.g. 5200-6000 ft)....they may run a bit rich at really high altitude but they'll be fine.  If you are concerned, the way to change things on a 4 stroke carbed bike is changing any of the following:  Air/fuel screw setting, needle height setting, needle size/shape, pilot jet size, main jet size.  All it takes is being able to get to the carburetor and change these things out.  The air/fuel screw setting you can change on the fly without taking apart parts of the carburetor.  The others can take more time depending on whether you can easily tilt the carb while it sits on the bike so you can get to the slide/needle on the top or get to the pilot/main jet on the bottom.  Unfortunately with my WR450F, its pretty much easier to literally remove the seat, rear shock and loosen the subframe to easily get to the carb. 

Others might chime in about the DRZ400 carb access for jetting changes....which again, I think is NOT the best choice for dual track riding (e.g. ATV width trails and 4 WD roads) and definitely too heavy for singletrack.

 

 

[dualsports]

I appreciate these responses. I think I am overthinking it because I got no idea how carbs work. Thanks for the responses, I'm stoked to go with my gut and get the DRZ400 over the WRR

[SilvFx]

10 hours ago, dualsports said:

I appreciate these responses. I think I am overthinking it because I got no idea how carbs work. Thanks for the responses, I'm stoked to go with my gut and get the DRZ400 over the WRR

Maybe you should consider a fuel injected bike given that "you dont know how carbs work" will likely translate into you have trouble jetting it properly or have trouble adjusting the jetting if it is not setup correctly when you buy it.  KTM/Husky, Beta, Yamaha, Honda do make fuel injected 4 stroke enduro models too.  Will need to pay more to get more current models but fuel injection for enduro bikes has been around since about 2010-12 or so on the 4 strokes.

If you do get a carbed bike, whether two stroke or 4 stroke it is better to jet it richer than leaner.  Too lean of mixtures can run too hot and burn holes in pistons.  The practical application is that if you jetted a bike for Denver @6K ft in altitude -- running in Denver will be just fine; running it a high altitude (8-12k) it will be getting more fuel than it needs or can burn....so it will run rich (like running a carbed car with the choke still on or partially engaged).  Not the worst thing in the world, but can make a bike run sluggish and not crisp and i suppose if it were too rich you can end up fouling a spark plug with too much fuel.

I am still struggling with your plans for your intended riding and why you are targeting these dual sport bikes because they dont necessarily match up with your stated intent to ride dual tracks and single tracks while you are up in the mountains doing some camping.  Maybe you arent certain about what riding you intend to do and want maximum flexibility with a plated dual sport.  Just know that maximum flexibility = doesnt do anything particularly well with lots of compromises and trade-offs to live with.

May I ask what is your budget?  And, have you changed or clarified what type of riding you intend to do?

 

 

 

[dualsports]

My budget is definitely a large factor in my decision. If I had 10 grand to blow I'd get a WR450f and put plates on it. And yeah I do know exactly what kind of riding I want to do. Alpine Loop type roads as well as mountain trails. The reason I'm trying to choose between a WR250r and DRZ400s is because no other bikes have such long maintenance intervals (miles not hours) as well as their cost to buy used. It's true that I don't know how carbs work but that doesn't mean I can't learn haha, I appreciate the feedback though brotha 

[ptgarcia]

For christ's sake, you don't need to know the ins and outs of carbs to be happy with and a successful owner of a carbureted bike. You'll be fine learning as needed. 

[SilvFx]

27 minutes ago, dualsports said:

My budget is definitely a large factor in my decision. If I had 10 grand to blow I'd get a WR450f and put plates on it. And yeah I do know exactly what kind of riding I want to do. Alpine Loop type roads as well as mountain trails. The reason I'm trying to choose between a WR250r and DRZ400s is because no other bikes have such long maintenance intervals (miles not hours) as well as their cost to buy used. It's true that I don't know how carbs work but that doesn't mean I can't learn haha, I appreciate the feedback though brotha 

Ok thanks for clarifying the riding you plan to do.  You can easily get into a lower hour used Enduro bike from KTM/Husky/Beta/Yamaha for $5-$8k and plate it (if needed).  No need to spend $10K+ on a new one.

Once you get out in the mountains and start hitting the harder 4 wheel drive trails, ATV trails, and Motorcycle only  trails, I think you are going to be quite disappointed with the performance of a dual sport bike like you are looking at.  You mentioned the WR450F....do you have prior riding experience or dirt bike experience?

If you have no experience, you might be better off just starting out on an aircooled trail bike such as a CRF230F or TTR230 or the newer CRF250F (fuel injected).  These are definitely cheaper....and if you buy used can often ride for a couple of seasons and sell for nearly the same price.

Just trying to make sure you have all the facts before you start buying bikes and provide any guidance based on my 45+ years of dirt biking in Colorado.  Maybe I am wrong, but I am thinking you arent from Colorado or you havent spent much time out here.  Are you a new transplant -- it's OK to admit it.  We promise not to haze you (at least not too much).

 

[dualsports]

I grew up riding dirt bikes in California so yeah new to Colorado but not to riding. Some WR250r riders say they experience power loss at altitude, some say they don't. Has anyone experienced significant power loss at altitude? Do you think a WR250 with ADV gear strapped on could still muster up a muddy skree-ridden hill climb at 13,000ft?  

[ptgarcia]

Yes, you will experience power loss at altitude. Doesn't matter if the bike is carbureted or fuel injected; less air make less power.

[SilvFx]

Pretty well known loss of HP formula for altitude.  Go ahead and google it.  Altitude in feet x .03 divided /1000.  Difference between Sea Level and 11k ft is 33% reduction.  About an 18% reduction at 6k ft.  Difference between 6k and 11 k altitude is a further reduction of 15% beyond the already reduced power output of 82% of that produced at Sea Level.  And, this formula assumes adjusted perfect jetting at a given altitude.  It can be reduced further by having fuel/air mix not be correct.

Anyone who says they don't experience power loss at altitude need to recalibrate their butt dynos.  To your question about WR250R loaded with ADV gear on a muddy and skree filled slope....no way.  Good luck with that.  Depending on steepness it will even be challenging on 300 2 stroke or 450 4 stroke on loose skree not even muddy conditions.  Not to mention the rider who will run out of gas quickly at 13k while trying  push or right your bike in challenging conditions.

Have a perfect example of that about an hour outside of Denver.  Ride from top of Webster Pass (12.1k) to top of Red Cone Pass.  I think Red Cone is about 12.9K and usually ridden one way down from Top of Red Cone to top of Webster Pass.

https://www.alltrails.com/trail/us/colorado/webster-and-red-cone-pass-trail