Shifting woes...

[craigsinclair]

2001 Rosso Mandello. 

 

OK, I'm going to try to describe the problem. When down shifting, when letting the engine "brake", the bike will slow down and when I go to downshift I'll pull in the clutch and go to shift down a gear and the shifting mechanism is "jammed." If I blip the throttle I can shift down no problem. My mechanic suggested that the clutch needed to be bled, or that the it was over-shifting. And it might need shift springs. So I've bled the clutch and replaced the shift springs. Plus, if I were to prematurely pull in the clutch on an upshift I would get the same binding. It can't overshift in both directions? 

 

Warped pressure plate? It's a single plate clutch. If the bike is in gear, I can pull in the clutch and if I go to push the bike I can feel it overcoming the drag in the transmission, like the clutch is still engaged but as the coefficient of friction is overcome the bike breaks past the friction and rolls smoothly. Truthfully, I've replaced all three shift springs, gear box oil, and bled the clutch. I haven't actually finished putting it back together again but I'm not confident that these steps have fixed the problem. 

 

Thoughts?

 

[footgoose]

my first thought is the dreaded aluminum flywheel is coming apart on you. I wouldn't think It would take very long to to do so once it fractures, but who knows? How long has it been acting up? How many miles on her?

[stewgnu]

I had that when i over-tightened the shift lever.

[Scud]

As Stew implies, the first place to look is at the linkage. Make sure it is totally loose and free - the lever should have almost no friction. If you put the little screw and nut on the front of the linkage backwards, it will rub against the starter and make it feel like the shifter is jammed or that it is not returning the center (ready for next shift) position after shifting.

 

If the clutch is dragging a little when you push the bike with the clutch lever in, take a look at the screw on the lever - the one that pushes into the master cylinder. If you turn that in a little, you might force more fluid into the slave - just enough to get it to release the rest of the way.

 

If the linkage is all clear, then take another look inside the pre-selector, using this thread as a guide:

 

http://www.v11lemans.com/forums/index.php?showtopic=19547

 

If you have the pre-selector off now, it's worth going through and cleaning up the contact surfaces as described in that thread. You'll notice an improvement in shifting action while it's on the bench.

[craigsinclair]

The bike has 35000kms on it, the problem has developed in the last 1000kms. Nothing was taken apart and reassembled as the problem arose so I'm pretty sure it's not interference with the starter housing from a misassembled linkage. When I took the linkage off the bike to get to the gear selector it was bind-free, everything was loose. Regardless, once the shift resistance has been overcome it shifts with ease in both directions, it's only if I pull the clutch in while the driveline is loaded (accelerating or decelerating) that the transmission jams. It's like pulling in the clutch doesn't unload the transmission, and if I blip the throttle with the clutch lever pulled in the bike will react for a half second (lurch forward) until the transmission disengages which is why I think it's in the clutch somewhere. It's consistent, as in it happens with every decelerating downshift. 

 

The preselector runs smoothly off the bike. None of the springs were misshapen or damaged, but I've replaced all three "just because." It's the older model without the banana plate. And now that it's back on the bike it seems to run through the gears smoothly.

 

And the clutch has been thoroughly bled. 

 

Maybe it will be fine upon complete reassembly, but the fact I haven't seen anything wrong with the parts I've serviced makes me think the problem hasn't been addressed. And checking in here on the forum seemed smart because it would have been nice to get a "this is the problem" while the bike was still apart.

 

I'm going to try turning in the screw on the clutch lever at the master cylinder to see if actuating the clutch a bit more solves the problem. Maybe the master cylinder is the problem? But what it really feels like to me is that pulling in the clutch doesn't unload the transmission which is causing the shifter to bind against loaded gears. 35000kms is a fair bit of mileage, but it's been mostly on the highway so not a lot of clutch play. It's the single plate clutch too, which Moto Guzzi didn't stick with for long so maybe there's issues with that as well.

 

OK. Back in the shop tonight, we'll see what happens after it's all back together. Thanks for the input.

[Chuck]

 

 

 It's the single plate clutch too, which Moto Guzzi didn't stick with for long so maybe there's issues with that as well.

 

Ya Think?? That = about 22K miles which is about as far as I've heard of a single plate clutch lasting. You *may* be sitting over a grenade. 

[Lucky Phil]

Like Chuck said if its done that kind of mileage on the originl single plate clutch then its about time to pull it down and replace the flywheel and clutch assy. The outcome for a failed unit is too severe and dangerous and its a matter of when not if.

Your shifting issue sound like clutch not gearbox to me.

 

Ciao

[cash1000]

That's a bit scary.My RM has just clocked over 40,000 km's. I've had it since 3,000 km's with no clutch or gearbox work. Clutch fluid is due for a change but doesn't look dark.

It occasionally gets a vague feel to gear box like its lost between gears when you change down while rolling to a stop. It also squeals a little bit when taking off quickly.

Will I get any warning that clutch plate is about to go?

[Lucky Phil]

That's a bit scary.My RM has just clocked over 40,000 km's. I've had it since 3,000 km's with no clutch or gearbox work. Clutch fluid is due for a change but doesn't look dark.

It occasionally gets a vague feel to gear box like its lost between gears when you change down while rolling to a stop. It also squeals a little bit when taking off quickly.

Will I get any warning that clutch plate is about to go?

Warning? not really its not the plate its the flywheel that fails and can take out the crankcases with it. http://www.v11lemans.com/forums/index.php?showtopic=16675

 

Ciao

[MartyNZ]

 

Will I get any warning that clutch plate is about to go?

 

Warning? not really its not the plate its the flywheel that fails and can take out the crankcases with it. http://www.v11lemans.com/forums/index.php?showtopic=16675

Ciao

More on that topic, with an interesting picture here:http://www.v11lemans.com/forums/index.php?showtopic=19510&page=2&do=findComment&comment=211566

Aluminium alloys do not have a fatigue limit like steel, so every power stroke leads the aluminum flywheel inexorably closer to eventually cracking. Then the cracks join hands. Then "pop".

Or is it "grind grind clatter"?

I don't know 'cause I have a two plate clutch.

[craigsinclair]

 

 

More on that topic, with an interesting picture here:http://www.v11lemans.com/forums/index.php?showtopic=19510&page=2&do=findComment&comment=211566

Aluminium alloys do not have a fatigue limit like steel, so every power stroke leads the aluminum flywheel inexorably closer to eventually cracking. Then the cracks join hands. Then "pop".

Or is it "grind grind clatter"?

I don't know 'cause I have a two plate clutch.

 

 

 

The fear of God has been put in me. That, and I suspect the problem has been the clutch all along, it was the shop that steered me down the path of clutch bleeds and gear selectors, though it was time to do both of those too so no regrets there. I'm going to order a clutch replacement kit today. Thanks. 

[footgoose]

 

 

More on that topic, with an interesting picture here:http://www.v11lemans.com/forums/index.php?showtopic=19510&page=2&do=findComment&comment=211566

Aluminium alloys do not have a fatigue limit like steel, so every power stroke leads the aluminum flywheel inexorably closer to eventually cracking. Then the cracks join hands. Then "pop".

Or is it "grind grind clatter"?

I don't know 'cause I have a two plate clutch.

 

 

 

The fear of God has been put in me. That, and I suspect the problem has been the clutch all along, it was the shop that steered me down the path of clutch bleeds and gear selectors, though it was time to do both of those too so no regrets there. I'm going to order a clutch replacement kit today. Thanks. 

 

 

 

Don't feel too bad. You're just discovering this potential problem. At least no catastrophe. Many of us have lived with the expectation for some time. I knew I'd have to fix it sooner rather than later though I have a low mile bike, 12k mi., with no problems. I've had a long time to come to the realization that it's just going to have to be done. It's not worth the gamble. Winter comes, and time for the fix.

[cash1000]

Is there a post that shows how to replace the clutch plate? Ideally with a better plate(s)

[Scud]

Here's one with a detailed parts list and some other links within the thread:

http://www.v11lemans.com/forums/index.php?showtopic=18068

 

Here's a well-documented story with some pictures:

http://www.v11lemans.com/forums/index.php?showtopic=17074&page=1

 

If you search for "single plate clutch" or "scura clutch" you'll get several more. There were more Scuras than RMs or Tennis - so the problems most frequently appear on the Scuras.

[cash1000]

Thanks Scud

I've got Tattley Rappit Rally end of month so bike will need to hold together for that. The rally is NZ's Moto Guzzi Rally

Otherwise on a mission.I emailed Peter Kelly of Motokiwi last night for price and availability

of parts need