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What RPM's with stock gearing at 70mph?

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I just got a DRZ 400s and i have been taking it back forth from college to home on the weekends, this means about 30 miles of going 70 - 75mph (as the stock speedo shows). What kind of RPM's is the motor at and is this too much for the bike to take for that long of a time?

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The DRZ is comfortable running 8k all day. I don't know what the RPM's would be thogh. I run mine down the highway, nearly wide open for 15-20 mi at a time. I've got no problems. If you're worried, get a smaller rear. Drop to a 41T and you will notice a huge differance.

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What is the final ratio?

Unless it has really been dropped, the final ratio not the bike, I wouldn't worry too much about going that speed for 30 miles. Just make sure you keep clean oil in it.

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I only briefly pass 70 so I don't know the exact rpm. I do however run WOT whenever I am on the freeway and have done so for numerous 160 mile stints. I only pull over because I am getting very near reserve if it had a bigger tank I wouldn't have to bother. A bgger bladder would help also, lol.

Other than tires and chains I have yet to need any significant repairs. Valves are still right where they were the first time I checked them at 300 miles. I will have 18000 miles by this weekend on a bike I purchased new about six months ago. Change the oil and let it rev.

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I just got a DRZ 400s and i have been taking it back forth from college to home on the weekends, this means about 30 miles of going 70 - 75mph (as the stock speedo shows). What kind of RPM's is the motor at and is this too much for the bike to take for that long of a time?

With stock S gearing, which is 15 / 44, and tire circumference of 82.5 inches (tire outer diameter of 26.2 inches) 73 MPH = 7000 RPM

There is an excel spreadsheet that calculates this floating around. Not sure if this will format right, but let's try -

Primary reduction 2.96

Secondary reduction 2.93

1st 2.285

2nd 1.733

3rd 1.375

4th 1.09

5th 0.863

Front sprocket 15

Rear sprocket 44

Rear tire circumference 82.5

Miles Per Hour

RPM 1st 2nd 3rd 4th 5th

1000 3.94 5.19 6.54 8.25 10.43

2000 7.88 10.38 13.09 16.51 20.85

3000 11.81 15.58 19.63 24.76 31.28

4000 15.75 20.77 26.18 33.02 41.70

5000 19.69 25.96 32.72 41.27 52.13

6000 23.63 31.15 39.26 49.53 62.56

7000 27.56 36.34 45.81 57.78 72.98

8000 31.50 41.54 52.35 66.04 83.41

9000 35.44 46.73 58.89 74.29 93.84

10000 39.38 51.92 65.44 82.55 104.26

11000 43.32 57.11 71.98 90.80 114.69

Bob

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awesome, even if my speedo is on the money im not really pushing it to hard at 75. Thanks for the info, its great.

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Noob question, but what is the "redline" of the motor?

Has anyone added a tach to their DRZ? I have found a couple tach/running time computers for pretty cheap for farm equipment that I am thinking of trying.

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I've wondered what the redline is also, but the general concensus here seems to be that if your not hitting the bike's rev limiter, don't worry about it :thumbsup: . Someday I'll have to forget to shift once, just to hear what the rev limiter sounds like? I have yet to hit it WOT in 5th.

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The other thing that keeps my highway speeds down is the annoying engine pitch change that kicks in around 65 -70. I've been told that it's the air box resonating? Anyone else get that?

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Noob question, but what is the "redline" of the motor?

Has anyone added a tach to their DRZ? I have found a couple tach/running time computers for pretty cheap for farm equipment that I am thinking of trying.

Redline for S is 10K, E/K is 10.5K, quads are 9.5K

Yes people have added a tach, just no real reason since the cdi has a very well functioning rev limiter.

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The other thing that keeps my highway speeds down is the annoying engine pitch change that kicks in around 65 -70. I've been told that it's the air box resonating? Anyone else get that?

I get that too I figured it was some kind of harmonic vvibration.

Does the 3x3 mod relieve that?

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I get that too I figured it was some kind of harmonic vvibration.

Does the 3x3 mod relieve that?

When you look at the Stock bike dyno HP curves, there is an odd dip/flat spot in HP at about 6500 RPM. This would possibly correspond to about the road speeds you mention. The old 2000 DR test report on exhaust systems shows that removing the rear insert, or going with an after market pipe eliminates the odd 6500RPM dip. It may be an interesting experiment to remove the insert and see if the effect is still there.

Bob

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