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Headwinds and losing power?

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I was riding my green DRZ-S today in Wyoming-like 30+ mph winds. I was riding north, and the winds were from the north-northeast. The bike would hesitate and slow down when the winds increased, it felt like the winds were sucking the air out of the airbox/carb. At full throttle, the bike would run just over 50 mph, and was really scary to keep it on the road.

- Does wind direction affect the bike's power and performance?

- Did the 3x3 mod have an effect?

- Should I block off that 3x3 mod?

OTOH, I had no problems riding the opposite direction, with a southeast tailwind. 75 mph was easy with less than full throttle. :bonk:

Anyone else have strange problems in high winds?

I have 15/44 gearing, stock carb, stock exhaust, 3x3 mod, jetted for 5000 ft.

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Headwind'll cause that. You're not real aerodynamic on a DRZ. The bike wasn't malfunctioning, when it hesitated and slowed you were just running into a wall of wind. The 3X3 mod shouldn't be affected nor should you block it off.

I've got an old XL250R that I can't even put into top gear with a strong headwind. Just doesn't have the torque at those speeds to keep the speed from falling.

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This may sound like "hocus pocus" (it is the internet, after all :bonk: )...

It's possible for crosswinds/sidewinds to change the pressure in the float bowl via the vent tube. I had a road bike (a GS1000S, years ago) that ran great until I passed a truck, and it would stumble until after I got away from the truck. The solution was to remove the vent tubes.

This may not be a good long-term solution, but it's definitely easy enough to pull them off & put them back on just to see if it's actually a problem.

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thats a common "complaint" with street bikes that have been converted to pods. Side winds causing it to stumble.

The real question was, was it "hesitating" as in it started stumbling/surging/running poorly, or was it running well

If it was running well, I'd say you were discovering how aerodynamically poor these bikes are. I once went across kansas on my ZRX with a 40mph head wind. It didn't prevent me from cruising at 80mph, but it did drop my mpg from 45 to 20. Just an example of how much power a strong head wind takes to counter

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...It's possible for crosswinds/sidewinds to change the pressure in the float bowl via the vent tube. I had a road bike (a GS1000S, years ago) that ran great until I passed a truck, and it would stumble until after I got away from the truck. The solution was to remove the vent tubes. ....

Very interesting. My bike started stumbling in heavy crosswinds comming from the direction of 10 o'clock. It is possible it was blowing across the vent tube, which is on my left side. If the crosswinds came from the other side (2 o'clock to 5), the bike had no stubling problems.

The bike would stumble (i.e., hesistate) suddenly when there was a sudden gust in the crosswinds. It felt like power was reduced, then come back when the winds were not as strong. With no winds, the bike runs well at 75+ mph. I will re-route the vent over the top of the carb, and away from the sides. I have to put a T in it anyway, so I might as well try this.

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+1 on the aerodynamic effect. I estimate that my top speed changes by 1 mph for every 2 or 3 mph of headwind (if I am sitting upright). A headwind gust at high speed can feel like a loss of power.

A 30 mph wind at 10:00 o'clock would have a 15 mph headwind component (= 30mph X sin(30 deg))--which could reduce your speed by 5 to 7 mph unless you applied more power.

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The carb vent is an interesting observation. Definitely anything that changes the pressure reference signal to the float bowl will affect "jetting". And you can fix some real elusive problems by changing the vent hoses. And yes head winds are a bitchh any way you look at it. I too had (have) a GS1000. Always got 50 mpg. For some reason when running into a head wind in ND I stopped early for gas. Sure glad I did. Was getting about 30 mpg. Sometimes I had to run 4th instead of 5th to maintain speed on a 1000cc bike.

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WOW - I just posted this last night...I thought I was hitting the rev limiter at

65mph..

https://thumpertalk.com/forum/showthread.php?t=490106

Yesterday was very strong winds...I'll bet 25mph to 30 which we were hittting head on. This might have been my problem too.

300 mile ride BTW...............lots of gravel, creek crossings, and twisties...besides the wind beating the crap out of me .....it was a great day

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As I mentioned earlier, my solution was to yank the tubes.

Does anyone have a proven solution, such as sticking the vent tubes into a catch bottle, or re-routing tubes to a different location?

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