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Discussion Starter #1
ive had different answers to this question, while shifting from neutral to first my bike seems to drop hard, seems a little violent. ive heard that this is typical for this bike and others have said it is not. it only seems to happen after riding for a while. any feedback, thanks!
 

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I think it's normal. From what I've heard the majority of people say. Mine does the same thing. I'm pretty sure the warmer your oil is the more noticable that First grar clunk is. It even rocks my bike forward a little if I'm not holding any brake.
How you liking your RC51?
 

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Pretty normal for a Honda drivetrain to be a little clunky especially going into 1st from a standing stop, however what you term as "hard" can be a very subjective adjective.

Ideally you need to compare it to other RC51's to get a really good idea. Keep in mind that even the brand and viscosity of the engine oil can affect transmission and clutch engagement and also be mindful that an excessively high idle can also cause a larger than normal clunk when snicking it into 1st gear as can an excessively worn clutch or insufficient throw from the slave cylinder.
 

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LDH® pretty much nailed it. Try changing the oil first and see if that helps.
But I just got to ask, why are you going into neutral anyway?
99.9% of the time my bike is in gear.. stop lights, in 1st gear. parking the bike, in gear.(come to stop in 1st, flick side stand, bike cuts off, pull key) :confused:
 

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When your gearbox is is neutral, the clutch basket and plates are spinning together.

There are no synchronizers on bikes to slow down or match shaft speeds as on cars, so when you engage the clutch and place it in gear, the rotating mass of the steel drive plates, friction plates, and hub have to suddenly stop.

That energy is conveyed to the output shaft, and onto the wheel.
A higher idle or engine engine speed means even more energy to suddenly stop.

Since these are wet clutches (meaning the clutch plates are bathed in oil), the viscosity of the oil can cause drag on the drive and friction plates as well.
Especially since the disengagement distance is not all that much.

These bikes use a hydraulic clutch mechanism, so it should automatically maintain proper clutch adjustment.
But on bikes that use clutch cables, the cable can stretch over time, allowing decreasing disengagement clearance with progressively less clutch disengagement, and therefore clutch drag.

Don't feel too badly about the clutch. Indy cars and older F1 cars use a similar method.
I've watched an Indy car in the pits shred a gearbox due to impatience.
Rather than allow the engine to idle or run a low revs, he revved the engine way too high and snicked into 1st.
The rotating mass of the clutch and gears at those RPMS sheared the engagement dogs right off.
The same can happen to bike as well.
 

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~

This is one reason why I change my oil every 1200~2000 miles (Depends on how hard I ride the 'ol girl;))

I know the gear box thanks me just by how smooth it shifts, which makes both of us happy :D

What type of oil are you running? (Not that I want to jack this thread into another oil thread)
 

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Discussion Starter #7
Usually I stay in gear as well, but the times I don't I have noticed it. Thank you all that helps..the bike is awesome and always gets tons of compliments.
 

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Staying in gear in stops/lights adds temperature due to clutch friction. I wait for ped/light to go red, pull the clutch all the way, wait 1-2 secs, then shift. This allows the shaft to slow down some before it engages.
Either the idle is set too high or you have clutch drag above normal if you compare to other RCs.
 

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The senior members are correct in every way.. Describing the effect of the action of the clutch..
May i add - that the clutch slave cylinder fluid, also has to be changed periodically.. The color of the clutch slave res. fluid can also be a determining factor to when the fluid needs to be changed (the lighter is better, the darker needs to be changed)
 

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The senior members are correct in every way.. Describing the effect of the action of the clutch..
May i add - that the clutch slave cylinder fluid, also has to be changed periodically.. The color of the clutch slave res. fluid can also be a determining factor to when the fluid needs to be changed (the lighter is better, the darker needs to be changed)
I've found that to be true for all the fluids, as a rule. But it can be different with the clutch fluid. (Only use DOT4.) I've gone through, complete take apart and clean, and replace a bunch of parts in my clutch system. I've changed and or bled the entire system about 3 or 4 times now. Regardless, that fluid gets dark looking within just a couple days. I've heard that from a couple other members; it rings true for my bike as well.

Edit: LDH makes a good piont, make sure your oil isn't old - like more than 2 or 3 months of your 100+ degree weather - and your idle should be 1300 rpm.
 

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Well, that's gonna have to wait just a couple months anyway. I've been pretty hard on my clutch this last summer. Self-teaching myself to blip, it can get ugly once in a while. I've pretty much got it, don't miss very much now, but I'm sure my clutch has paid a price. Plus I still get that occasional SP1 clutch judder. So I'm looking at a barnett kit w/springs, and a shift star. (Although I don't really understand the shift star)
 

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I don't blip... I stopped blipping the throttle years ago when I started using Brembo Master Cylinders and race calipers etc...

The blipping action caused my fingers to inadvertently put pressure on the brake lever causing the brakes to pulsate and alter my trail braking efforts. Trailbraking is an essential part of my riding style from altering the bikes geometry to get it to steer properly into the turn to loading up the contact patch on the front tire. I use trailbraking techniques to a greater extent than any other facet of my riding and I need every ounce of feel I can get out of the front end to insure I am not exceeding the limit. Blipping the throttle upsets the front end and causes additional gyroscopic precession inside the engine that I can simply do without.
 

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Well, that's gonna have to wait just a couple months anyway. I've been pretty hard on my clutch this last summer. Self-teaching myself to blip, it can get ugly once in a while. I've pretty much got it, don't miss very much now, but I'm sure my clutch has paid a price. Plus I still get that occasional SP1 clutch judder. So I'm looking at a barnett kit w/springs, and a shift star. (Although I don't really understand the shift star)
I blip I-4's....not so much with the V twin.:cool:
 
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