Neutral to 1st gear makes bike kinda jump?

[rsmith2072]

Hello I just bought my 2007 FZ6 a few days ago. It only has 8,500 miles on it. So i am new at the FZ6 forums. I have searched this and haven't found any threads on it yet. The bike shifts pretty good through all gears but when its in neutral and i shift into 1st gear it does it kinda hard. It makes the bike kinda jump a little. So my question is this normal or is there an adjustment to be made or is it an oil problem? Thanks in advance for any support!

 

[red_rock_beetle]

the first gear on a FZ is a little twitchy anyways, but try adjusting your clutch cable

 

[Erci]

Totally normal. Having said that.. do change the oil (motorcycle-safe synthetic works great on fz6) and make sure clutch fully disengages when squeezed.

 

[darius]

Welcome, Blue Clan. Nice bike.

A solid, but reassuring "thunk" when you kick it into 1st is normal. The bike might push forward slightly, especially if the engine is cold. Pulling in the clutch a few times to loosen it up might help, but it's not a problem.

Be sure to check your tires for age, wear and I'd recommend changing all the fluids.

 

[PFD023]

trying to find the article in Cycle World about the very same issue....I think it was in the Service section.....still searching The mechanic/editor (Paul Dean) explained in full detail why and how it happens. Wet clutch and the plates tend to stick together due to the oil (wet clutch)......two very smooth surfaces which are wet with oil will kinda "suck' to each other......heavier the oil the more they "suck".....you are breaking the plates apart when you shift. I think they refer to it as "oil drag"....plates still spinning while you try to put it into gear. Do a search online and you'll see dang near every make of bike has riders concerned about it.
Article by Paul Dean said not to worry at all.....completely normal and expected.

Some of the comments I've read elsewhere is that the riders put their bike into gear....push it forward abit....then start it.....breaking the oil drag prior.

Thicker the oil and "possibly" more oil drag.
One of the downsides I guess of not using automotive oil for wet clutches....due to the friction modifiers which would cause the plates to slip all the time.

 

[rsmith2072]

WOW! You guys are awesome! Thanks for the support.

Im going to change all the fluids this weekend. The tires look pretty good, they have about 7000 miles on them. They do have really small cracks on the top edge of the tires but they are not deep and they do not look dangerous. But i will replace them anyways as soon as i can!

 

[PFD023]

Please forgive the source (I kinda like cruisers too).....but here is another source of info on your issue (and ours).....summary is this

"I should mention that, by nature, wet clutches suffer from something called viscous drag, particularly when they're cold. Viscous drag occurs when the viscosity of the cold oil creates enough drag between the plates to transfer some torque, even though you're holding the clutch in. If the drag is severe, punching the bike into gear can result in a loud clunk and maybe a small leap forward, or even a stall. Normally, this is only a problem when the bike is started for the first time on a cold day, or too heavy an oil is used, but the solution here is simple. Just let the bike warm up for a minute, preferably with the clutch disengaged, during the first start of the day, before putting it in gear."
The source is here -

Read more: How To: The Ins and Outs of Clutches - Motorcycle Cruiser magazine


The same thing will happen when you put the bike up on the centrestand and start the engine with the bike in neutral.....the back wheel will spin.....so I've been told.

 

[FZ09Bandit]

Yes the back wheel will spin about 5-7mph. Mine clunked like what you describing from the factory. Unless it developed it in the 14 mikes I didn't ride it

 

[rsmith2072]

So i changed all the fluids and it helped. If i pump the clutch before going to 1st helps to. Thanks for all the help!

 

[The_Paragon]

I'd check out your idle RPM too. Mine set from factory was nearly 1300 rpm. Now that i have 4000 miles on the bike I turned it down to about 900. 1st gear jump is much less violent.
I read somewhere on this forum that idle rpm is supposed to be turned down after break in.. Not sure on the source of that information though..

With that lower idle, be prepared to use a little more throttle on take off though, or you migh find yourself clunking it out!

 

[trepetti]

In a 'dog box' (a transmission WITHOUT synchronizers) all shifts are harsh. Overly simplified, in neutral the drive gears are spinning because they are driven by the engine through the clutch, and the driven gears are spinning too because they are floating free. When you pull the clutch the drive gears are still spinning because the clutch doesn't fully disconnect, it just loosens. It can't transmit much torque, but spinning the trans in neutral does not require much torque.

Now you select 1st, and the driven gears latch to the driven shaft and STOP because the front sprocket is not moving. The driven gears now stop the drive gears by requiring more torque then the disengaged clutch can deliver. The energy of the rotating gears is dissipated both ways....to the engine and to the front sprocket. The engine slows a little (immeasurably) and the front sprocket jumps, resulting in a lurch and clunk.

So you will ALWAYS get a clunk...but too big a clunk can be caused by a sticky clutch (plates, wrong grade oil, not releasing enough because of adjustment), idle speed (more rotational energy means more energy dissipated when 1st is selected) and perhaps other things.

Take care of the basics by ensuring the oil is right and idle speed is within spec.

 

[regder]

I'd check out your idle RPM too. Mine set from factory was nearly 1300 rpm. Now that i have 4000 miles on the bike I turned it down to about 900. 1st gear jump is much less violent.
I read somewhere on this forum that idle rpm is supposed to be turned down after break in.. Not sure on the source of that information though..

With that lower idle, be prepared to use a little more throttle on take off though, or you migh find yourself clunking it out!

900rpm is way too low, manual specs the idle to be about 1250-1300rpm if I remember right.

All bikes that I've ridden jump when going into first gear after sitting for a bit. As mentioned above, the clutch plates stick together, going into first gear effectively breaks them apart from one another. With our wet clutch, there's nothing pushing the plates apart except the force of the engine.

To me it sounds perfectly normal, I wouldn't worry about it

 

[Nelly]

All brilliant explanations, one thing I do in the winter when its really cold is, with the engine off I change down into first and then back into neutral before starting the engine. This certainly helps.

Neil:thumbup:

 

[rsmith2072]

Yes you are absolutely right. My RPM is at 1300 at idle. I will check the specs to see what it recommends. Thanks!