New Rider...

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ajay

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Hi All,

After a break of 3 years and watching from the shores, i finally took the plunge and bought a 2008 FZ1(Preowned, $6000 OTD, 4300miles).

So one of the concerns that i have about the bike is that when i change gear from Neutral to 1st with bike standing still and clutch lever fully pressed, the bike gives a loud thud and jerk with a slight forward motion; I ensured that the clutch lever is fully engaged. After shifting if i open the throttle(with clutch engaged) i dont feel the bike going forward (to make sure clutch is not loose).

Everything else seems to be fine with the transmission...

Any apparent reason why I am seeing this behavior?

-AJ
 
ajay said:
Hi All,

After a break of 3 years and watching from the shores, i finally took the plunge and bought a 2008 FZ1(Preowned, $6000 OTD, 4300miles).

So one of the concerns that i have about the bike is that when i change gear from Neutral to 1st with bike standing still and clutch lever fully pressed, the bike gives a loud thud and jerk with a slight forward motion; I ensured that the clutch lever is fully engaged. After shifting if i open the throttle(with clutch engaged) i dont feel the bike going forward (to make sure clutch is not loose).

Everything else seems to be fine with the transmission...

Any apparent reason why I am seeing this behavior?

-AJ
Click to expand...

Well AJ, welcome to the forum bud. Glad your back among the two wheeled ranks again. Good choice to go with the FZ. The tranny in these bikes are a bit clunky from nuetral to first. Nothing wrong with that, it's normal, however, please elaborate a little more on whats happening when you shift. I don't quite understand what your saying. When you say that you don't feel the bike going forward, what do you mean by that?
 
Make sure the clutch free play is properly adjusted and you may want to change the oil and then see how it behaves. My '06 is kind of like that when cold, but once it warms up a bit the clunk into 1st gear is not as noticeable. I think there is probably nothing wrong with it...
 
Interestingly, the longer you hold the clutch in at a stop, the less of a clunk you get going into first.

Try it; hold the clutch in for like 10-15 seconds and go into first, it's a very light click.

Squeeze the clutch and go into first immediately, CLANK.

This leads me to believe there must be a part in the clutch that "spins down" when you squeeze the clutch. Giving it a few seconds to spin down an the shift to first is less jarring.

Try it, works every time on mine...
 
^^^ Absolutely. I like about 1/2" play in my clutch handle (at the end). I think that's the big end of spec, but works good for me.
 
Before I start let me say that I am not a FZ1 owner and know very little about them. You may have a problem but I suspect that you do not.

Your bikes drive train goes something like this:

Engine->Clutch->Transmission->Chain->Wheel

Lets say that your bike is started, in neutral, with the clutch out. The engine is spinning, and because the clutch is not pulled in, this spinning motion is transfered to the transmission.

In the transmission there are two shafts, an input shaft shaft and an output shaft. The input shaft has a bunch of gears on it that all connect to a corresponding gear on the output shaft. The gears on the input shaft are directly connected to the input shaft, but the gears on the output shaft are on bearings that allow them to spin at a different speed than the output shaft.

transmission-simple.gif

In the picture above the green shaft is coming from the clutch, the red shaft is the input shaft, the gold shaft is the output shaft. The purple collar allows you to select which blue gear the output shaft is connected too, when the bike is in neutral none of the blue gears are connected to the output shaft. The gold shaft leads to your chain and therefore your tire. When the bike is not moving the output shaft is not spinning.

The clunk:

The clunk occurs for the following reason. As stated earlier your bike is in neutral with the clutch out, this causes the input shaft in the transmission to spin, but because you are in neutral none of the output shaft gears are attached to the output shaft. The output shaft is stopped because the bike is not moving. Pulling in the clutch disconnects the input shaft from the engine allowing you to select first gear without the engine instantly becoming connected to the back tire. However, the input shaft is still spinning due to momentum. If you instantly select first gear after pulling in the clutch, the output shaft suddenly becomes connected to one of its gears which stops that gear from spinning. As this gear is directly connected to the gear on the input shaft the input shaft also stops spinning. The sudden stopping of the input shaft results in a heavy "clunk".

If you start your bike in gear with the clutch pulled in, the input shaft never spins up so it doesn't gain any momentum so there is no clunk. If you pull the clutch in and leave it in for a few seconds as boomer talked about the input shaft has a chance to spin down, lessening the severity of the clutch.

Summary: I don't know enough bout the FZ1 to be sure nothing is wrong but I think the clunk you are talking about is a jerk from part of the transmission being forced to stop suddenly as it becomes attached to your rear wheel.
 
:ditto: All that makes perfect sense. I don't think there is anything wrong with his motorcycle either. Mine will clunk also as I stated above, especially noticeable when the bike is cold and the oil is thicker. I will try the little experiment of holding the clutch in for 10-15 seconds before shifting into 1st gear.
 
I experimented a little with this today; it doesn't take 10-15 seconds, more like 3-4 seconds. If you shift into 1st immediately after squeezing clutch you get a good clunk. 2 seconds later a very light one. 4 seconds, you barely feel it.
 
Welcome to the forum. Your bike is normal and it's not just an FZ1 phenomenon. My M109R, VRSCD, DL650 and now the FZ1 all do the same thing. You'd think the manufacturers could eliminate the neutral to first "clunk" but they don't seem to be too worried so you shouldn't be either. You'll learn to live with it. Also remember that the gear cluster in these things has to be pretty beefy to deal with the H.P. and torque they produce.
 
Thanks...

Changed the OIL and tried the "pull clutch for 5 secs" suggestions.

Works like a charm.

:sport12:

Thanks every one! Getting used to the awesome acceleration... whenever northwest weather allows. :)
 
ajay said:
Changed the OIL and tried the \"pull clutch for 5 secs\" suggestions.

Works like a charm.

:sport12:

Thanks every one! Getting used to the awesome acceleration... whenever northwest weather allows. :)
Click to expand...

Well we're in the crap weather now. Congratulations on your new ride!
 
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