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DRZ Jetting Question: Altitude

Joined
Feb 28, 2017
Messages
66
Location
Fort Worth
I'm a new DRZ owner learning how altitude requires jetting adjustments.

I have an upcoming ride going from 4000 ft to 8000 ft and back in a span of only 24 hours. What elevation do you adjust the jetting to, the 4000 feet or the 8000? Or do I do the average between the two? I have read that taking the air filter cover or snorkel off will help it breath at high altitudes. I would hope that a simple trip wouldn't require adjusting them during the ride! That seems kind of ridiculous to have to do but maybe I have to. Thanks!
 
Joined
Dec 20, 2008
Messages
374
Location
granbury, tx
i have a 2013 drz that i ride in tx and co i jettin mine for 5000 ft it will run in tx or 12000 ft looses power up high .but i ride in texas more works great .jd jet kit fuel screw fmf pipe 3x3 air box mod.but i ajust fuel screw when we get to co .hope that helps .the best fix was 2015 fe 501 fi problem solved :sun: when the altitude gets high just cant go full throttle .but it made all the passes in colorado
 
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Joined
Dec 20, 2008
Messages
374
Location
granbury, tx
i would highly suggest the jet kit and air box mod realy wakes up that little motor .dont qoute me but i think i read it gives it 6 hp with the pipe but feels like 10 or more
 
Joined
Feb 28, 2017
Messages
66
Location
Fort Worth
TD, thanks. So you have it set for 5000 ft here in Texas and it works good for both here and Colorado? I will also need to learn how to mess with that fuel screw.
 
Joined
Dec 20, 2008
Messages
374
Location
granbury, tx
it does okay in both could be better but i dont have to rejet when i haul it co .runs fine here no popping or back fire on decell
 
Joined
Oct 16, 2008
Messages
1,889
Location
Bryan, TX
The fuel screw only affects idle or slightly off idle. I've never had a problem with a stock carb at 10,000 feet. I remove the left side cover and it runs just fine. I do run a K&N air filter. Multiple trips to NM, CO, and UT.
 
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Joined
Feb 28, 2017
Messages
66
Location
Fort Worth
Thats interesting. This is what I have stock: pilot 22.5 and main jet 142.5. Do you think it would run fine with leaving it as is going up to 8000 ft (Cloudcroft) and taking off the air filter cover if it starts acting up?
 
Joined
Oct 16, 2008
Messages
1,889
Location
Bryan, TX
Those are both stock so I don't think you would have any problem at 8000'. You may have to remove the side cover.
Adjusting the idle mixture screw:
1. Remove the plug
2. Lightly screw in the mixture screw while counting turns
3. Return to stock turns (should be about 2 to 3 turns)
4. Start the engine and warm up the bike
5. Set the idle to as low as it will smoothly idle
6. Turn the screw in slowly until the idle starts to fall off or miss
7. Turn the screw out until the idle starts to fall off or miss, while counting turns.
8. Set the screw half way between 6 and 7
You may have to adjust the idle during step 7
An alternative way is to just adjust the screw to the highest idle speed.
The final setting should be between 2 and 4 turns out. If less than 2 (it won't be) then the idle jet is too large. If more than 4 (it might be) the idle jet is too small.
 
Joined
Feb 28, 2017
Messages
66
Location
Fort Worth
Thanks very much. Last clarification. Would I need to do the idle mixture screw as well as the filter cover removal or would the filter cover removal be enough?
 
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