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V7II Cush Drive

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jefrs View Drop Down
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    Posted: 29 Sep 2018 at 23:57
How much play should one expect on the cush dive of a 2015 V7II?  

With the bike in gear on the centre stand (or jack), how far should the wheel rotate back and forth loosely before it encounters resistance?

Is the cush drive in the wheel hub?
How easy is it to replace the rubbers?
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Brian UK View Drop Down
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Post Options Post Options   Thanks (1) Thanks(1)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 30 Sep 2018 at 07:57
There should be no play in the cush drive, the rubber inserts should hold the wheel without movement.
If you have the wheel off the ground and are turning it back anf forth, you will get movement which is backlash in the gearbox. It's highly unlikely that the cush drive will give problems unless it's been assembled incorrectly.

Take the wheel out and you will see all.
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Andyb View Drop Down
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Post Options Post Options   Thanks (1) Thanks(1)   Quote Andyb Quote  Post ReplyReply Direct Link To This Post Posted: 30 Sep 2018 at 11:39
The cush drive rubbers are individual pieces of rubber that go in the hub of the wheel, behind the bevel.  As Brian has said, remove the rear wheel and as you will see them.
I can’t imagine they could be assembled wrong, there is no room in the hub.
My V7 is not in front of me but I would guess 5mm of rotation at the tyre is normal backlash as it is a summation of play in bevel / splines / UJs between wheel and gearbox.
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jefrs View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jefrs Quote  Post ReplyReply Direct Link To This Post Posted: 30 Sep 2018 at 14:44
I'm getting a lot of rotation of the wheel up on the centre stand before the slack is taken up and resistance is felt.  Maybe 4 to 6-inches at the tyre.

I'm not sure how much is backlash and how much is cush; certainly more than 5mm. The gearbox and drive is behaving normally, no issues there.

Do I assume the rubbers are shot?

But having just done the rubbers on the Enfield, similar age and mileage, it was the rubbers and made one hell of an improvement. Yes, the rubbers do wear out. Getting the wheel out of the Guzzi will be a little bit more complicated
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Brian UK View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 30 Sep 2018 at 16:28
No, they all do that sir. That's the backlash in the transmission as a whole but mainly in the gearbox.

Andyb, by assembled wrong I really meant assembled with some missing.


Whatever you do, do not ever run the engine on the centre stand, in gear. The noise will scare you to death.
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Mike H View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike H Quote  Post ReplyReply Direct Link To This Post Posted: 30 Sep 2018 at 18:12
Originally posted by Brian UK Brian UK wrote:

No, they all do that sir. That's the backlash in the transmission as a whole but mainly in the gearbox.

+1

Don't know about new V7's but on the old Tonti's you also had to add on the play of 4 splined joints.

"Chicken nuggets don't dance on a Tuesday."
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Post Options Post Options   Thanks (0) Thanks(0)   Quote V7Chris Quote  Post ReplyReply Direct Link To This Post Posted: 30 Sep 2018 at 18:47
Originally posted by Brian UK Brian UK wrote:


Whatever you do, do not ever run the engine on the centre stand, in gear. The noise will scare you to death.
What, more than sitting at the Traffic lights between two panel vans with the clutch out you mean! Wow that must be scary. I looked around to see where the concrete mixer had stopped......
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 30 Sep 2018 at 19:04
It's not the clutch noise, it's the transmission rattling with the uneven beat of a v twin.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jefrs Quote  Post ReplyReply Direct Link To This Post Posted: 30 Sep 2018 at 19:11
I don't think it can all be free play in the gearbox because of the way it makes slow cornering jerky going on and off the throttle.

The movement is very free with no sound of the shaft turning, then resistance is felt and then I feel the backlash of which you speak.  The movement is a short hand-span.

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Post Options Post Options   Thanks (1) Thanks(1)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 30 Sep 2018 at 20:51
The jerky throttle is also a known issue and is generally considered to be a fuelling issue.

Take the wheel out and look for yourself. You will see the rubbers and the vanes which go between them so will easily be able to tell if there is any play there.
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jefrs View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jefrs Quote  Post ReplyReply Direct Link To This Post Posted: 01 Oct 2018 at 10:22
Originally posted by Brian UK Brian UK wrote:

The jerky throttle is also a known issue and is generally considered to be a fuelling issue.

Take the wheel out and look for yourself. You will see the rubbers and the vanes which go between them so will easily be able to tell if there is any play there.


A jerky throttle is a feature on most electronic fuel injection.

An example of the symptom I'm on about might be taking a mini-roundabout where you have to move forward, slow to negotiate the hump and accelerate gently away, slowly because you're in traffic. This can be done by keeping some power on and dragging the rear brake, with the clutch slipped.

When I replaced the cush rubber on the Enfield the kick up the bum as the brake comes off went away, everything is now smooth taking slow turns. Beforehand the Enfield had only a couple of inches of play, less then the Guzzi has now, but if anything the Enfield torque is even lower down, it will walk away at idle, needing gentle use of the throttle for slow speed.

On the Guzzi the power come up without a massive flat spot, decelerating into the turn and then accelerating gently out is producing a pretty big kick up the bum as the force on the drive reverses direction. To use the rear brake to take up the slack, the Guzzi needs more throttle kept on. This needs a fair amount of brake and with the clutch slipped the engine is racing.

I also want to change the foam in the air box breather (full of oil, needs cleaning), which needs the wheel out. This is turning into a fairly major job.
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Mike H View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike H Quote  Post ReplyReply Direct Link To This Post Posted: 01 Oct 2018 at 10:36
Originally posted by jefrs jefrs wrote:

The movement is a short hand-span. 
Yes so it was also on my Tonti bikes. 

"Chicken nuggets don't dance on a Tuesday."
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Mike H View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike H Quote  Post ReplyReply Direct Link To This Post Posted: 01 Oct 2018 at 10:40
"On the Guzzi the power come up without a massive flat spot, decelerating into the turn and then accelerating gently out is producing a pretty big kick up the bum as the force on the drive reverses direction. To use the rear brake to take up the slack, the Guzzi needs more throttle kept on. This needs a fair amount of brake and with the clutch slipped the engine is racing."

Yes sounds familiar. I hated having to do small roundabouts. 

"Chicken nuggets don't dance on a Tuesday."
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 01 Oct 2018 at 13:55
I know this might sound odd, but how much slack do you have in the throttle cable? Many, including myself, have found that reducing this slack to the absolute minimum does reduce that snachiness you describe. You just need to be sure that turning the steering from lock to lock has no effect on the tickover speed.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike H Quote  Post ReplyReply Direct Link To This Post Posted: 01 Oct 2018 at 14:38
+1, I've had to do this. 

Try roundabouts on a maxi scooter with automatic clutch and CVT and too much throttle play ShockedShocked

Know all about throttle snatch then


"Chicken nuggets don't dance on a Tuesday."
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