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Team,

I saw a youtube video where a guy named horse replaced his clutch with a "performance" clutch and EBC heavy duty springs. I'm hoping he's a member here and will also respond to his youtube comments. In the video, he describes not having to rev as high on the interstate due to the new clutch gripping better.

I have 33k miles on my vn900 and 3rd gear definitely slips if I'm trying to speed away and interstate travel is not enjoyable due to the bike having to rev so high (no 6th gear problem). I have replaced both front and rear pulleys with Baron pulleys and installed a taller tire. I also have Ivan's ECU and a hard krome 2.5" exhaust.

I'm interested if the reason my bike has to rev so high on the interstate is due to the clutch slipping? Would installing a new and therefore grippier clutch truly reduce the interstate revs? I may replace the clutch anyways due to mileage and it seems it's only $300~ or so and easy to take out the old install the new.


Thanks,
Brent
 

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Installing a performance clutch would not change the rpms of a bike that has a good clutch. The system is either engaged or not. The differences of a performance clutch over stock is a more solid quicker engagement and less tendency to slip under hard use. High performance clutches are recommended for modified high power engines, trikes, pulling a trailer, and bikes with sidecars.
 

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As Tourer notes changing a clutch will not change the engine RPMs in any gear since when engaged it has nothing to do with the mathematical relationship between the engine and final drive components. If engine RPMs increase without disengaging or manipulating the clutch lever in any gear without any change in road speed then the clutch is slipping and will need to be adjusted ASAP per the manual, or otherwise it will self-destruct.
 

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As Tourer notes changing a clutch will not change the engine RPMs in any gear since when engaged it has nothing to do with the mathematical relationship between the engine and final drive components. If engine RPMs increase without disengaging or manipulating the clutch lever in any gear without any change in road speed then the clutch is slipping and will need to be adjusted ASAP per the manual, or otherwise it will self-destruct.
I have installed an exhaust, tuner, and air filter and I’m having issues with clutch slipping when I really get on the throttle in any gear. Would this performance clutch help?


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I believe all 900 without 6th gear have a similar problem.
That is the reason to change sprocket sizes, tires sizes, ect....
 

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Hi EasyMac. If your clutch is adjusted properly and it is slipping it is time for replacement. If I was replacing my clutch, would go for a higher performance clutch and springs.
 

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I noticed the clutch on the 900 I put back together has a very short disengagement range when I pull the lever. It begins to disengage after only about 1/4" of lever pull, and that is with play in the cable adjustment. I would guess if the cable is adjusted too snuggly there could be some slippage
 

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Rc4man, due to the straight forward clutch cable design of the VN900, the service manual says you need to adjust the gap between the moveable and the fixed part of the clutch handle to a 2mm gap. I think this is not enough of a gap, because it puts the disengagement point too close to the released handle position. I use a 4mm gap, to make sure the clutch is fully engaged when the handle is released. With this increased gap, the clutch engagement/disengagement feels perfectly normal to me.
 

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I'm interested if the reason my bike has to rev so high on the interstate is due to the clutch slipping?
This is also a hard question to answer because of the relative nature of the question. A high revving motor to one person might be totally normal to another. MPH matched with RPMs in a given gear would be great, but most of us don’t have a tach.

It’s also complicated by the speedometer issue, which I think is corrected when I replaced my tire and pulley. So now I’m actually doing 80 when my speedo says 80. I don’t know how I’d verify that with any accuracy, tho, other than getting pulled over. “Do you know how fast you were going?” “Actually, I was hoping you’d tell me!”

I don’t have a tach on my bike, but after changing the rear tire and rear pulley, it’s noticeably better on the highway (it revs lower at 80 than it used to). Also, when riding around town, third gear is where I spend most of my time, and when getting onto the highway, I generally take 4th gear up to about 60-65 before needing 5th.

Your mileage may vary.
 

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Mike, you could verify your speedo with a couple of methods. The modern way is to use a GPS. The older way is to use the mileage markers on the side of the highway and a watch. For the older way, you hold a certain speed (usually 60 MPH) and time how long it takes from one mileage marker to the next one. Pick a flatter part of the highway to make it easier to hold the speed. If the result is less that 60 seconds, your speedo shows slow. If the result is more than 60 seconds, the speedo shows fast. You can do the math, or adjust the speed up or down to get 60 seconds between the mileage markers. Then you know exactly how far off your speedo is.
 

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The older way is to use the mileage markers on the side of the highway and a watch. For the older way, you hold a certain speed (usually 60 MPH) and time how long it takes
Ah, that’s great! So simple!
If I’m lucky enough to have a warmish day and I’m off, I’ll def try that.


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I generally take 4th gear up to about 60-65 before needing 5th.
This is where I have a problem with the gearing change. Unless I was accelerating hard, I would normally shift into 5th between 45 and 50 mph. I didn't need to downshift into 4th until I got down to 40. On my annual 100 mph run, I would hold onto 4th until around 95. One of the things I loved about my 900 (and miss on my 1700), is that I could ride from 35 mph to 105 mph without having to shift gears unless I wanted to. This engine was designed for higher revving than most larger V twins and using pulleys to lower the gearing drops you lower in the power range and requires more downshifting,

I realize that it's a matter of opinion, but I could ride my 07 900 Custom all day long a 80 mph with a completely stock setup and the revs never bothered me.

Whatever you do, enjoy the ride!
 

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Better way to check your speedometer - find a location that has an active speed sign - shows your speed - very simple.

only solution to a clutch problem is the 6th gear add o_O
 
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