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Discussion Starter #1 (Edited)
what's up all,
So I have a question about the bike's responsiveness, I'm trying to understand if what I've been observing is normal or not. If I'm in 1st at a stop light, when the light changes I'll release the clutch and open the throttle a little more that half way, the bike will pull and and usually by the time I'm across the intersection the speedo will hit 20-25mph, tach will hit maybe 5500 and then I'd shift up. 2nd gear takes me to 40mph or so within the same RPM range, point being is acceleration is smooth, the speed and the tach seem to be pretty close to being in sync. This all seems normal to me.

What I'm questioning is when I'm on the highway. If I'm doing 55 to 60mph, the tach reads 4500 and if I want to pass someone or get some separation I'll roll on the throttle, usually not WOT, the bike seems to rev but speed climbs slowly. tach will go up to 6500-7000 but I feel like I have to give it a little more to get it going. So here's what i'm unsure about, same scenario, doing 55mph, open the throttle quickly (almost WOT) and the tach will jump to 7500 and it almost feels like I'm shifting into this magical 6th gear, the tach will drop to 6000 and I get a rush of torque and before i know it I'm going close to 80mph.

Is this normal? Is my clutch getting weak or needs adjustment? or is this an early spline issue symptom? Do I need to lose weight lol? Or am I simply over thinking this? I've been searching but can't find a post that describes the exact same situation.
 

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Not sure, but sounds like you're describing clutch slippage.

If at 55 mph and you go full throttle, does the rpm keep climbing while the speed is slow to increase?

Or try this. . At about 30-35 mph in 3rd, go full throttle. Do the rpms increase a lot with the speed.just gradually rising?

5500 rpm to shift out of 1st might be a bit high. The shift to 2nd is less harsh at around 2500 rpm, I'm usually shifting out of 1st at 2300 rpm.
 

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If I understand you right, you’re saying the tach will drop 1,500 rpm although you have not moved the throttle?
That’s weird to me. Seems like if you open it up to 7,500 rpm it should stay there. Does kind of sound like the clutch is slipping.

Normally when the clutch slips the revs stay at one spot but the bike feels it’s losing speed.
If there’s a disparity between throttle position and engine speed, you might have a sticking slide, or some other carb issue.

From what you described here, it sounds like the latter. Run some Sea-foam through the bike and make sure your cables and throttle linkage are adjusted right.
 

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Discussion Starter #4
Sorry I was trying to be detailed but not too log winded, glad you both mentioned clutch and not splines

So to answer your questions:
Spockster, Yes at 55mph if I slowly roll the throttle it feels that I'm increasing RPMs and speed increase is slow, it DOES increase but slower than what I expect. I haven't quite tried what you described in 3rd gear, I normally don't push it so hard in 1st but was trying to duplicate the issue.

KM,
You're understanding me correctly, I open the throttle (let's say 3 quarters open) the bike roars, RPMs will climb steadily but speed increases slowly. At 7000-7500 without letting off the throttle it'll drop momentarily and then i'm off to the races. To my untrained internal dyno it feels like a load is applied.

I'm fairly religious with my seafoam use, every other tank for the most part. I have recently adjusted my clutch cable, I noticed a couple weeks ago the rib was not lined up. I followed the manual and the one detail that i struggled with is it states that the cable connection to the clutch release lever should be 70-80 degrees, when lined up mine looks like it's at a right angle, The free-play at the handle feels dead on so I'm not 100% sure if i should redo that and give it a test ride.
 

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it does sound like clutch slippage to me as well.

1st gear is to get the bike rolling, not much more. sure you can rev it out to about 50 if you take it up near redline, but it not needed. 2nd is where I always did most of my accelleration.

clutch slippage can be caused by lack of free play in clutch cable (it must have some free play or the pressure plate will never fully squeeze on the clutch stack) or an oil issue. make sure you use wet clutch safe motor oil in the engine (motorcycle specific is best, but you can use some regular motor oils that are NOT 'energy conserving' with good result). of course, the friction discs may be wearing out as well.

test in 3rd as spockster suggested, that will confirm clutch slippage. if it does not slip in 3rd, try 4th.
 

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A lower gear that's already making higher rpm is less likely to produce clutch slippage when the throttle is opened quickly.

A higher gear that's giving you a lower rpm is more likely to produce clutch slippage when the throttle is snapped wide open.

Can try this: About 30-35 mph, put it in 5th and snap it to full throttle. If the rpm rises a lot and speed is slower to rise, it's slipping.

Or you can use 5th at even slower speed, snap the throttle open, and see what happens.

That 6th gear feeling you had may have been the clutch beginning to grab again.
 

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Discussion Starter #7
I’m going to try these scenarios you’re all suggesting. Does anyone think it could simply be my cable adjustment I mentioned?
 

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You said you have free play, so it may not be adjustment.

Sometimes you can tell by how far the adjustment is out, compared to where the clutch starts to grab.

If the adjuster is screwed out a lot, and the lever is almost completely out by the time it grabs, you're probably dealing with worn out discs.

However, on mine, the difference in slipping and.not slipping was about 1/8 of a turn on the lever adjustment.
 

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Discussion Starter #9
Guess it’s time to start troubleshooting. It’s good that all responses kinda zeroed in on the same culprit.
 

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Splines would be more like a ratcheting, jerky sort of slipping and you would hear some snapping or grinding directly behind you.
 

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Discussion Starter #11
Ok, Went through the adjustment procedure again, this time I took note of the position of the adjusters before I started for sanity. It appears I may have had the mid-span open a little too much. I went through the tests you all mentioned and only got a tiny slip in 3rd but no major drop in RPMs as before. Jumped on I-95 and took it to redline in both 4th and 5th with no slips. Didn’t have to rev it as high to gain speed and engine braking is even more effective and that torquey shaft drive feeling is back.
Thanks to all once again for your help.
 
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