Lag/Play when changing gear

[nilesh_b]

Hi All,

I have noticed every time i change gear, i feel after few milliseconds that the sprockets(I know i am not using the correct term here but something is engaging with the shaft - Bike is chain drive of course!) are engaging or something being engaged and then rear wheel gets power.

I am not sure if i am describing my problem clearly or not.

Its never a smooth/straight delivery to the rear wheel - From the stand still (Bike in Neutral), Pull clutch and select first gear. Now release the clutch slowly as you accelerate. Once the clutch is half way, i feel a thunk and then rear wheel starts rolling. This was felt in almost all gears except sixth.

:banghead:

Same when changing downwards, pull clutch and drop into fifth/fourth/third gear then release the clutch. I do notice thunk(this time it will be quicker than the change from first to second or from second to third gear though)

Bike has done 3.8k miles - Will it disappear once bike gets old?

Is this the normal behavior?

 

[Boneman]

Well the ol FZ6 does have a bit of a heavy clutch and a very small friction zone. It's either on or off. So that could be the issue. You can try playing with and adjusting the clutch cable in and out to see if that helps.

Might also want to check your chain tension. If your chain has stretched a bit and has too much slack, you might nees to tighten it up a bit. Too much chain slack can cause symptoms like you are having.

 

[RJ2112]

The smaller possibility is that the rubber cush drive is somehow buggered up.... inside the rear sprocket, there is a rubber bushing to help cushion the impact of engaging the driveline.... The sprocket assembly has cogs on the back of it, that fit into the rubber spacer, which then connects to the slots in wheel hub. The sprocket doesn't drive the rear wheel directly... it pushes the rubber which then pushes the hub/wheel. If that part is worn excessively, you would get the sort of on/off clunk you describe.

If it's missing, it would be quite noticable.

Item 8 in this schematic.

2005 Yamaha FZ6STC FZ6 OEM Parts, 2005 Yamaha FZ6STC FZ6 OEM Replacement Parts - BikeBandit.com

 

[nilesh_b]

The smaller possibility is that the rubber cush drive is somehow buggered up.... inside the rear sprocket, there is a rubber bushing to help cushion the impact of engaging the driveline.... The sprocket assembly has cogs on the back of it, that fit into the rubber spacer, which then connects to the slots in wheel hub. The sprocket doesn't drive the rear wheel directly... it pushes the rubber which then pushes the hub/wheel. If that part is worn excessively, you would get the sort of on/off clunk you describe.

If it's missing, it would be quite noticable.

Item 8 in this schematic.

2005 Yamaha FZ6STC FZ6 OEM Parts, 2005 Yamaha FZ6STC FZ6 OEM Replacement Parts - BikeBandit.com

hey RJ2112,

thats exactly what i was suspecting but being a bike only less than 5 months old with < 4k mls, i thought it shouldn't have been damaged. I could have been missing altogether?

 

[andrewm]

Thanks Boneman for saying it has a heavy clutch. I had not ridden bikes in about 15 years and after putting about 2000km on mine inf the last few months I have to say the clutch is really heavy. After a 3 or 4 hours my clutch hand is very sore. I don't remember this on the 550s i used to ride 15 years ago.

Oh well guess I need to work my left hand more... ;-)

Andrew

 

[abacall]

Or try to lube the clutch cable, that will help greatly.

 

[RJ2112]

hey RJ2112,

thats exactly what i was suspecting but being a bike only less than 5 months old with < 4k mls, i thought it shouldn't have been damaged. I could have been missing altogether?

If you bought the bike used, someone may have done some bad maintenance or something. It's (remotely) possible it got left out on a tire change or some such.

Should be pretty easy to check for play between the sprocket and the rear wheel hub....

I'd put the bike on the center stand in gear, and move the back wheel. You can expect SOME play from the front sprocket as the slack comes out of the chain... what you'd be looking for was any movement of the rear sprocket after that, with respect to the rear wheel hub. They should move together, no play at all.

 

[nilesh_b]

I loosened up the clutch cable by adjusting ring dial thingy before clutch lever. It has almost gone now and the clutch has become very comfy and less stressful.

cheers all.