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at what RPM do you shift?

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or with the DRZ's lack of tachometer, approximately what speed in what gears?

The reason I ask...a couple weeks ago some buddies and I were on our way out from work. This group includes a Buell S-1 lightning, a cafe'd rat bike interpretation of an 81 Honda GL500, and a Ninja ZX-12R. Naturally the DRZ is short on the acceleration department with these bikes (except the Honda) so I was twisted as far as it would go and shifting at higher RPM than I had before. I noticed a very uncomfortable sounding buzz from the engine area at what I think to probably be 8k RPM or so, and the power just fell on it's face.

For some reason I now find myself wanting to accelerate faster and this is coming up and making me very nervous...and I can't figure out whether something happened and this is a power loss situation, or it's all in my head and I'm now actually waiting longer to shift and going past the powerband, and never did that until two weeks ago...which would also be very strange. The part that makes me feel like I might just be paranoid is that the bike gets through the gears REALLY fast, but it doesn't feel like it's got the same torquey pull that it had when I was new to the bike. It doesn't feel like anything's slipping because I can make the bike jerk by quickly changing throttle openings.

I'm more used to cars so I don't have a good feel for what a certain RPM "feels" like, but according to this calculator

http://www.gearingcommander.com/

this seems to be happening around 8k RPM.

Because I know someone's going to ask:

3x3, stock exhaust w/ modified end cap

155 MJ, 25PJ, extended screw, 4th clip on blue needle

MCCT installed.

1100 miles on the bike, until now I've ridden it fairly easily. This is my first streetbike and only my second bike ever so I'm riding harder as I've become better at it.

I found a thread that kindof described a power loss situation somewhat similar and it turned out the timing chain had jumped a tooth, so I checked and the timing is good.

The ONLY thing I have changed recently is I started running regular gas instead of "premium", and everything I know about gas and the DRZ is telling me that shouldn't matter. I get it at whatever station is most convenient when I hit reserve.

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This is just advertising, and someone else will probably have a better link, but torque and power curves for the stock DRZ are given in this advertising brochure:

http://www.akrapovic.com/typo3conf/ext/user_products/mod1/uploads/documents/21a7716eb81d612232ced06d9b1fc0e7.pdf

Last page. Looks like about 8K and the motor is starting to run out of puff.

HTH,

John

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I really wind my SM out. During those times, I'll shift right as it hits the rev limiter.

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with the stroker kit i shift at 7000 rpm .. i have a vapor , the shift light activates at 8000 rpm . shifting at 7000 rpm makes use of the motors torque .

no real need to rev it any more unless i need to defend against the CRF's

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I could probably shift just before 8k and avoid the noise and the power fall-off...for some reason it just feels natural to try to keep going, and feels like I'm short shifting if I don't.

By 9k, are your bikes making a buzzing noise like the engine is about to grenade?

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That noise has got me so bothered I'm seriously considering doing the primary nut fix tonight...I've been justifying to myself that the bike is still under warranty, but with my trip to Colorado coming up I can't have the bike go down days before we leave.

I don't even know that the noise and power loss are even related, but both bother me.

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Mine does make the noise, from what i have found out its the airbox resonating. worried me when i first got it but seems everyone has that issue, used to it now and use it as a shifting point. Right when i start to get the buzz i move on... unless i need the juice then i throttle through it...only lasts about 1000rpms till its past the harmonics...

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My bike still feels strong at 9K. Once I get above 6K, the revs build so quickly, that I am at 9K before you know it. If I shift earlier than that, I either have to be just cruising gently along or else it feels like I am short shifting.

Hitting the limiter in 1st, 2nd and 3rd is a very common occurence. During yesterdays ride, nailing the throttle at 70 in 5th (about 6,200 rpm), 100 on the Vapor showed mighty quick.

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Mine does make the noise, from what i have found out its the airbox resonating. worried me when i first got it but seems everyone has that issue, used to it now and use it as a shifting point. Right when i start to get the buzz i move on... unless i need the juice then i throttle through it...only lasts about 1000rpms till its past the harmonics...

so this is the airbox noise I've read about? I had read it happening at highway cruising speed on S models so I thought this was at too high of an RPM to do it. Maybe the 3x3 airbox hole moves it up in the RPM range?

I plan on getting a Yosh RS-2 within the next six weeks, I expect that to let it breathe more up there in the RPM. I'll have to rejet again at that point too so I may tinker with it and make sure I don't have a main jet issue. Normal drivability is otherwise perfect.

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