Clutch lever travel changed again!

[John in PA]

I had a problem with too much freeplay at the clutch lever and a "squashy" feel a few weeks ago. I spent a good deal of time bleeding the clutch system and almost eliminated it. Now it's back, probably 300 miles later. I never have had to touch the clutch on the Norge or Breva 1100, or V11 Sport for that matter. They just work every bit as solid as a cable. What is it about the Stelvio that it seems folks have more trouble with this?? The reservoir is full. How does "new" air get into the system after it's already been bled extensively and worked properly for a while? What am I missing here?

I'm going to bleed it again this weekend, but I don't want to keep this up!

 

[draidt]

Have you checked if all the banjo bolts are tight enough ? It could also be a bad banjo bolt sealing washer in the clutch hydraulic system.

 

[John in PA]

No *apparent* leaks of fluid. I'd think pressurizing the system with the lever would squirt/drip fluid out rather than sucking air in(??) I'll run over it and tighten everything I can find before bleeding again.

But I think several others reported clutches dragging after running for a while also. And that bleeding gave either temporary or permanent(?) fix for the issue?

 

[Greg Field]

All the 1200s have a new clutch design in which there are four different lengths of throwout pushrod, which presumably allows the assembler to select the correct one to keep the throw of the slave cylinder within range of the normal throw requirements of the single-plate clutch. Too short a pushrod, and the clutch may not de-clutch properly. Too long a pushrod, and pulses from the engine can push back the piston in the slave cylinder, in the same way that a badly warped brake rotor can push back the pistons in a caliper. Aprilia had horrible problems with this on the '04 and later RSVs. I'm guessing that this might be what's going on.

 

[John in PA]

So have I got a warranty problem? How do I diagnose??

 

[Wonder B]

I don't have that problem with mine, but boy how I wish this lever was softer... When I ride into Paris and have to make numerous gear changes it hurts after less than an hour... (and I have a solid grasp which I trained heavily when I was doing squash at high level a few years ago)

 

[RJVB]

Ditto here. It's not actually that it's particularly hard, but it's so damn far ... and the 4-step tuning is far from effective enough.

I had the mechanic have a look at this at the last revision (they had to change the lever anyway, from my last accident at the traffic light). So far all I can see they've managed is reduce the travel (making it harder to "feather the clutch" :S) ... though it's hard to tell whether I'm not imagining this

 

[Greg Field]

John in PA wrote:

So have I got a warranty problem? How do I diagnose??

John: I do not know for sure what it is. I'd document it as an issue with your dealer. I'd even have him flush and refill the system so it is documented that it was done by a dealer's tech. If that does not cure it, they're going to have to dig deeper. I brought up the pushrod thing as one of the possibilities.

As for the lever effort issue, perhaps we can convince Evoluzione to make a slave-cylinder kit for the Guzzis?

 

[John in PA]

RJVB wrote:

Ditto here. It's not actually that it's particularly hard, but it's so damn far ... and the 4-step tuning is far from effective enough.

I put on a pair of Pazzo levers (same ones as the Norge) Workmanship is flawless, and they have a positive, logical, six step adjustment for reach. I found the stock Brembo levers numbers for adjustment totally random, and three positions were nearly identical to each other, the last made a SLIGHT difference.

 

[John in PA]

I bled the system again today, this time with a vacuum bleeder. It feels solid again, as it did before, (after bleeding with a little one-man bleeder bottle). I filled the reservoir to slightly over-full. I've only taken a short ride so far, I'll report on how it goes from here.

I don't see how air can get back into the system once it's bled, unless there was a hole in the bellows(??) All my connections seem to be fluid-tight. If it gets spongy again, I'll call my dealer and get him to check with Guzzi technical.

 

[RJVB]

I've been considering them, but since I've just gotten a new pair of levers (the clutch lever on somebody else's insurance), I'm hesitant to go that route. Esp. since they apparently lack the copper/bronze bushing and thus could wear quite quickly (?)...

 

[Greg Field]

John:

Is air getting in? Do you see it coming back out when you bleed?

 

[John in PA]

I've got 2 trips back and forth to work so far (maybe 50 miles max?) I'd say 1/3 of the excess free-play is already back. I'm gonna take a LONG ride today and see what happens.
Is there any way the piston travel on the master cylinder can affect this, like if it moves too far in or out at either end of the stroke??
I did change the lever, but measured the length of the small operating arm that pushes the piston and matched it's adjustment on the new lever when installing. I have NO evidence of fluid leaking anywhere.

Greg: I don't actually SEE air coming out, just the lever function improves after bleeding. Do you think I'm just moving the same air bubble around without removing it? Does it's location in the system have anything to do with the lever travel? I would have thought that the location of the bubble in a sealed hydraulic system wouldn't have made a difference(?) Air in the piston itself?

 

[john zibell]

John

Air has to be somewhere. Just because fluid doesn't get out, doesn't mean air doesn't get in. Air is thinner than the fluid. Possible entry points are at the bleeder, or a bad piston at the MC, even a scored cylinder at the MC that has finally worn the seal on the piston, plus any of the joints.

First step, try using teflon tape on the bleeder screw the next time you bleed. Also inspect the bleeder and the seat for any scratches on the sealing surfaces. If after bleeding the free play returns, the problem is elsewhere. Second step, if still under warranty, ( as a US Stelvio I assume it is) take it to a dealer as the cure should be covered by the warranty.

 

[guzzi jon]

I put on the Pazzo levers, great by the way. I needed to adjust the small doohicky quite a bit to get the sucker to work right. I suggest you screw the little sucker in a bit and give it a go.... I needed to move mine in more than the same measured distance from the original lever, perhaps the geometry is a bit different. Once I did, no problems for over a year

 

[John in PA]

guzzi jon wrote:

I put on the Pazzo levers, great by the way. I needed to adjust the small doohicky quite a bit to get the sucker to work right. I suggest you screw the little sucker in a bit and give it a go.... I needed to move mine in more than the same measured distance from the original lever, perhaps the geometry is a bit different. Once I did, no problems for over a year

Move in as in, lengthen the push rod, or shorten the push rod?

 

[Greg Field]

John:

If air's getting in, you should see it coming out when you bleed. If an air bubble were just being moved around, lever travel would be consistent. I'd suspect the master cylinder first.

 

[John in PA]

Thanks all for the advice and input. I'll try a warranty claim for the master cylinder and see what happens.

 

[guzzi jon]

John in PA wrote:

guzzi jon wrote:

I put on the Pazzo levers, great by the way. I needed to adjust the small doohicky quite a bit to get the sucker to work right. I suggest you screw the little sucker in a bit and give it a go.... I needed to move mine in more than the same measured distance from the original lever, perhaps the geometry is a bit different. Once I did, no problems for over a year

Move in as in, lengthen the push rod, or shorten the push rod?

Shorten the push rod as in greater clearance

 

[kwn306]

John,

When I first got my Stelvio I felt the clutch action was weak, I asked my stealer about it and he claimed all MG where that way.

When I got home I put the bike on the side stand, grabbed the clutch lever, pull it in all the way and tied it to the handle bar / grip, then turned the bars fully right and walked away from the bike. I came back two days later, untied the clutch lever and the action felt perfect.

I learned this trick a long time ago to get air out of a hydraulic line on a m/c. Try this before replacing anything else, there could be a few air bubbles trapped in the line somewhere and by opening the master cylinder (pulling in on the clutch lever and tying it open) and turning the handlebars to the right, this gets the master cylinder into its highest local and the air bubbles will work there way up the line and into the master cylinder.

It's worth a try anyhow.