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Discussion Starter #1
On the DRZ vs. WR-X comparison, for me, the main difference is a carbureted bike versus a fuel injected bike. I have a few questions for those in support of carburetors and I couldn't find an answer to these few questions. I am aware that the answer could vary slightly when talking about different carburetors but I'm specifically interested in the DRZ.
#1: What elevation change requires a carburetor adjustment? In other words, how many feet of elevation gain or drop until you need to adjust the bike?
#2: Say one goes riding from one side of a mountain range to the other with a carbureted bike. How difficult is a carb adjustment out in the boonies?
#3: What are the consequences of riding a carbureted bike outside of it's comfortable elevation range? Severe damage or just less than optimum performance?

Thanks in advance!
 

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I believe for every 1000' of change you are dealing with approximately 0.50 psi of pressure drop atm. They have adjustment tables for this as far as jetting goes. First off, I don't have a lot of trails experience as I only ride street or track and stay at one main elevation. I don't want to give you the wrong answers for #1 and will leave that to the people with jetting experience.

2. Correct me if I'm wrong, but the only thing that you can adjust on the fly is your pilot jetting at the carb, which is mainly your 1/4 throttle and below. You can't adjust main jetting, or needle settings unless you essentially stop and remove the carb. In your case you would tune for the worst case scenario.

3. Depending on where you start elevation wise it will run more lean or rich as you change in elevation. The higher the density the leaner it will be.
 

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Discussion Starter #3
Ok thanks so much. That's makes me think carburetors are a thing of the past if you can't even do large elevation changes. It sounds irritating.
 

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I have a DRZ and in the 2 years and 15000 miles I have ridden and owned it, I have never once touched the carb. I have ridden this bike from Cincy, OH to Washington, DC, then down to Charlotte, NC, through Asheville and NC and back to Cincy a few times. Also took the bike out to the Dirty Bronson and didnt mess with the carb. It will be fine once its set up :thumbup:
 

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Discussion Starter #5
I have a DRZ and in the 2 years and 15000 miles I have ridden and owned it, I have never once touched the carb. I have ridden this bike from Cincy, OH to Washington, DC, then down to Charlotte, NC, through Asheville and NC and back to Cincy a few times. Also took the bike out to the Dirty Bronson and didnt mess with the carb. It will be fine once its set up :thumbup:

Maybe it was fine, but it seems to me that a bike with electronic fuel injection that adjustment automatically to give your bike the best performance would be so much better. I suppose that a carbureted bike like the DRZ would be totally capable but FI seems way more optimal for performance, fuel economy, and peace of mind that I'm not running it super rich or lean. I'm not trying to start a carb vs. FI thread. I was just curious about those few questions. Thanks guys!
 

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FI will give the best results no matter where you are at with no tweaking along the way but a carb will do the same thing, it Just needs to set it up and so long as you dont go WWAAAYYYY outside of parameters it will get the job done. You asked about WRX vs DRZ. Last time I was in NC I went riding with my buddy who has a WRX. Even with a pipe, programmer, and regear he couldnt hold against my stock carb'd dizzer which was set up for riding in Ohio over 500 miles away.

If you are considering buying a DRZ you arent going to get optimum performance :lol: The carb will be fine :thumbup:
 

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Discussion Starter #7
FI will give the best results no matter where you are at with no tweaking along the way but a carb will do the same thing, it Just needs to set it up and so long as you dont go WWAAAYYYY outside of parameters it will get the job done. You asked about WRX vs DRZ. Last time I was in NC I went riding with my buddy who has a WRX. Even with a pipe, programmer, and regear he couldnt hold against my stock carb'd dizzer which was set up for riding in Ohio over 500 miles away.

If you are considering buying a DRZ you arent going to get optimum performance :lol: The carb will be fine :thumbup:
Thanks for the reply and you're probably right about performance. When I said optimum performance, I didn't mean the fastest bike. I meant the best performance that the particular engine can muster, whether it's a 250 or 400. However, your argument for DRZ power and ease of carburetor use is persuasive. Thanks!
 

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I have a DRZ, and regularly ride from 1800ft to 5000ft with no issues. Sure, you lose a bit of power, but so does the FI bike as it compensates for the lack of oxygen by leaning the mixture as well. I personally prefer a carb myself. I can re-jet a carb super cheap for the addition of say a full pipe, not so with FI. I also prefer the smooth seamless feel of a well tuned carb, haven't like the abruptness of the FI systems I've ridden yet.
 

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Discussion Starter #9
I have a DRZ, and regularly ride from 1800ft to 5000ft with no issues. Sure, you lose a bit of power, but so does the FI bike as it compensates for the lack of oxygen by leaning the mixture as well. I personally prefer a carb myself. I can re-jet a carb super cheap for the addition of say a full pipe, not so with FI. I also prefer the smooth seamless feel of a well tuned carb, haven't like the abruptness of the FI systems I've ridden yet.
I suppose I'd be satisfied with either system. I just think that FI sounds easier and more clean. It might be a bit more expensive when it fails but I can handle that. Thanks for the input. You've made my decision wayyyy harder haha! :headscrat
 

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I suppose I'd be satisfied with either system. I just think that FI sounds easier and more clean. It might be a bit more expensive when it fails but I can handle that. Thanks for the input. You've made my decision wayyyy harder haha! :headscrat
I have owned many (and currently own) of both systems. Yes, major elevation changes with a carb'd bike can suck for racing but if you are not racing then you can generally get away with just adjusting the fuel screw (assuming you spent $20 for an externally adjustable fuel screw and took the 2 minutes to install it) a bit.

However, if you own an EFI bike and spend $400 for a PowerCommander EFI module and the AutoTune O2 sensor integration then you can have a rolling dyno that continually optimizes the bike at any elevation. Sure, EFI will adjust the fuel system without the power commander and auto-tune but stock fuel mapping from the factory is always very lean to pass emissions: basically as shitty as a stock carb that hasn't been jetted.

In either case you need to tune both systems. You can't expect to buy a bike and not change the fuel settings. Now, you may want to know that carb'd bikes have been ridden to over 18,000' elevations.
 

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Discussion Starter #11
In either case you need to tune both systems. You can't expect to buy a bike and not change the fuel settings.
I'm not expecting to not tune a bike. I'm just talking about once it has been tuned, it seems like a carb'd bike is not the best choice because I'm a bit of a perfectionist and knowing my bike was running perfectly at all times being monitored by a fuel injection system would make me happy! But carbs are simple and I could learn to work on one too. I think I'll just get the bike I like most and not worry about whether it carb'd or FI'ed because I'll be happy with either.
 

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I'm not expecting to not tune a bike. I'm just talking about once it has been tuned, it seems like a carb'd bike is not the best choice because I'm a bit of a perfectionist and knowing my bike was running perfectly at all times being monitored by a fuel injection system would make me happy! But carbs are simple and I could learn to work on one too. I think I'll just get the bike I like most and not worry about whether it carb'd or FI'ed because I'll be happy with either.
It really depends where you plan on riding it. If you live in the mountains and go over a lot of passes, then EFI is 100% the way to go - even to the point of that being the deciding factor between models. Having the bike bog and stall and be a bitch to hot start when the jetting is off is so overly frustrating that it can drive you to madness. That is specifically why I sold my 07 TC450 and bought an 08 TE with EFI. I lived near Tahoe and did rides with lots of elevation changes (+/- 4000 feet), the carb'd bike sometimes wouldn't kick over and I'd just be sitting there kicking and kicking for 5 minutes hating life. EFI solved the issue because you can't just take the carb apart and change mains.

However, if you are only seeing +/- 1000 feet of elevation change on a regular basis then either carb or efi is going to work just fine. In fact I love working on my SMR's carb, there's something beautiful about the non-computerized simplicity... and knowing it will start with a dead battery by pushing it makes me happy. EFI will not do that unless you have a capacitor style bike (RMZ) and the cap isn't drained.
 

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Discussion Starter #13
It really depends where you plan on riding it. If you live in the mountains and go over a lot of passes, then EFI is 100% the way to go - even to the point of that being the deciding factor between models. Having the bike bog and stall and be a bitch to hot start when the jetting is off is so overly frustrating that it can drive you to madness. That is specifically why I sold my 07 TC450 and bought an 08 TE with EFI. I lived near Tahoe and did rides with lots of elevation changes (+/- 4000 feet), the carb'd bike sometimes wouldn't kick over and I'd just be sitting there kicking and kicking for 5 minutes hating life. EFI solved the issue because you can't just take the carb apart and change mains.

However, if you are only seeing +/- 1000 feet of elevation change on a regular basis then either carb or efi is going to work just fine. In fact I love working on my SMR's carb, there's something beautiful about the non-computerized simplicity... and knowing it will start with a dead battery by pushing it makes me happy. EFI will not do that unless you have a capacitor style bike (RMZ) and the cap isn't drained.
Hm... Ok. Well I don't live in the mountains, but I do plan on doing many mountain rides. Perhaps EFI is the way to go. I agree with you on the beautiful simplicity of a carb though.
 

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Carbs are really only for if you're scared of FI or just enjoy fucking with mechanical things. I fall into the latter category so I prefer carbs, but I have to admit there is no logical reason to prefer them over FI besides initial cost. Saying "if your FI breaks you have to replace some parts" is like saying "your carb float might rupture and need replacement and flood everything oh god." Sure it happens, but not often.

The DRZ is still the bike I'd prefer because CHEAP USED PARTS. For a carb adjustment, you'd pretty much need a pair of screwdrivers and some extra jets on most bikes. Haven't done that one, I'd give it a half hour the first time, less thereafter. You could also cheat it a bit and adjust the fuelscrew if you aren't running WOT for a long time. Not sure how effective this is real world, more than nothing I'd wager.
 

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Discussion Starter #15
Carbs are really only for if you're scared of FI or just enjoy fucking with mechanical things. I fall into the latter category so I prefer carbs, but I have to admit there is no logical reason to prefer them over FI besides initial cost. Saying "if your FI breaks you have to replace some parts" is like saying "your carb float might rupture and need replacement and flood everything oh god." Sure it happens, but not often.

The DRZ is still the bike I'd prefer because CHEAP USED PARTS. For a carb adjustment, you'd pretty much need a pair of screwdrivers and some extra jets on most bikes. Haven't done that one, I'd give it a half hour the first time, less thereafter.
Yeah I'm not mechanically inclined but I could learn. I just like newer technology like FI. It does seem to be the best way to go for many reasons.
 

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Ok thanks so much. That's makes me think carburetors are a thing of the past if you can't even do large elevation changes. It sounds irritating.
If your really worried about elevation changes check out Holtzman engineering, they make automatic elevation adjusters for snowmobiles and I'm sure it would work just as well on a carbed bike. I know they work well on the small liquid 440s, when I used to ride sleds a lot of the guys were big into these things.

http://www.holtzmaneng.com/
 

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Discussion Starter #17
If your really worried about elevation changes check out Holtzman engineering, they make automatic elevation adjusters for snowmobiles and I'm sure it would work just as well on a carbed bike. I know they work well on the small liquid 440s, when I used to ride sleds a lot of the guys were big into these things.

http://www.holtzmaneng.com/
What would be the advantage of this over EFI? Cost?
 

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If your really worried about elevation changes check out Holtzman engineering, they make automatic elevation adjusters for snowmobiles and I'm sure it would work just as well on a carbed bike. I know they work well on the small liquid 440s, when I used to ride sleds a lot of the guys were big into these things.

http://www.holtzmaneng.com/
Although I love my FCR, it's pretty obvious that carbs are a dead technology when the Scary Fast site has everything 50% off and all the R&D and Boysen carb stuff is just sitting on retailer shelves.
 

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Discussion Starter #19
Although I love my FCR, it's pretty obvious that carbs are a dead technology when the Scary Fast site has everything 50% off and all the R&D and Boysen carb stuff is just sitting on retailer shelves.
Agreed.
 

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Mehhhh, just hold out and wait for electric supermotos. That, or for a diesel KLR with street rims.

Just kidding :laughingr

I've got a KLX400 (DR-Z400) motarded with stock jetting. My elevation is 4500'. I ride over the Big Horn Mountains (WY) all the time (9800' pass) and the carb'd KLX runs. It loses power fo sho, but it will still run on stock jetting. The plug is never too black, and I've never had a fouled plug. I have rejetted other bikes to run better for my elevation, and there is improvement to be had doing that. But back to your original question... I'd say unless you ride elevation changes greater that 2000 or even 3000 feet from start to finish, I'd say forget about carb tweaking. Anyways, if you get the DR-Z you'll more than likely do all the usual mods (3x3, exhaust, carb to FCR) so you can worry about jetting then. The only thing in my limited experience FI is good for at my elevation is instant starting and no screwing around waiting for the choke to come off, and less time waiting for the throttle to respond when in is under 35 degrees out.

Enjoy your purchase! :thumbup:
 
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