Clutch lever and heat?

Sorry for posting Stelvio query in the GRiSO forum but this is such an excellent source of help.

I have ridden my stelly now from Terrace BC to Las Vegas across to Carmel CA and now on my way home, currently in Fraser Valley.
Some days rode in 5c and bits of snow in mtn passes to 45c heat in vegas, in some cases almost that amount of change in the same day. Bike is a 2014 NTX, mods - canisterectomy, Beetles stelvio Map, Tuning by me as per all Petes info and aluminum wheels instead of the spoked ones, little windscreen i got from a fellow ghetto member.

Bike is a rock solid and tires are even wearing nicely with a full load of stuff i didnt need. With Petes tuning advice and Beetles map this machine is a dream to ride.

The only issue that is coming up is with the clutch lever, I have the pazzo levers and they are adjusted just right but ended up bleeding the cluth line roadside in Nevada as it was like it had air and we did get some air out, now 5 days of riding later it seems like its got air in it again, it gets better with the engine hot etc but its not right and its not consistant. Almost like the little pushrod on the lever is moving back n forth throughout the day but I have confirmed the little set screw is tight. I also checked the actuator where it attaches to the gearbox, those bolts are tight, no sign of clutch fluid leaking anywhwere. The clutch works but when cold its just doing its thing enough to let me put it in gear stopped at idle, once hot its better but not always.
What else can I check? Could air be getting in somewhere over time? Some days riding 10 hrs or so with with quite bit of change in temps. Not sure what else to consider.

Perhaps time to completely replace the fluid - how long since this has been done?

Its still less than 20,000kms on the bike in total and during the roadsie bleed in Nev we must have pretty much done that. Is there more to replacing it all than just bleeding?

Not unless there is still air in there, or a way for air to get in. Mine is coming up to 90,000 km and still has the original brake and clutch fluid in; not to mention still the original HH pads in the front. Me likey engine brakes; front brakes for emergencies only; rears are probably suffering from trail braking syndrome, and were replaced around 60,000 km.

Maybe I am just a soft pussy, the way I ride.

Check that the master cylinder pushrod in the clutch lever pivot is tight, if loose they have been known to unwind seeming as though you are losing hydraulic operation.
Or are you losing clutch fluid?
If so it could be a leak at the slave cylinder, my old GRiSO leaked past the seal in to the gearbox housing so there was no obvious external leak.

no obvious fluid loss, just rode another 4hrs this morning on way home and its working normall but I had to pump the lever a couple times before starting out to get it working, once home I am goong check every connection, banjo bolt and the lever assembly.

I can't even imagine what it looks like inside the tubes and reservoir with the original fluids after 90,000km.
I changed mine at 30k and the cultch fluid was as black as it can get.
And the reservoir was filled with all kinds of debris

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So after riding all day yesterday without issue, the bike sits overnight and now this morning cold the lever needs to come in all the way to the bar before it just barley has pressure to operate the clutch. Its like it pressures up when the engine is hot, I didnt think this normal but maybe I just have too much free play regarding the pushrod on the lever.

Bled it this morning and got another gulp of air out, air is getting in but cant figure out where or how. I did notice the little rubber cap on the bleeder nipple had some fluid in it so I put a little thread tape on the threads, would think there would be a o-ring or something there for a better seal when its closed. Anyone ever get air in this way? After the bleeding the lever action is back to normal but for how long...

>I put a little thread tape on the threads, would think there would be a o-ring or something there for a better seal when its closed.

As far as I know, the bleed nipple seals via a tapered seat. Should not need thread tape at all, and that tape may not be rated for brake fluid.
Have you crawled underneath and checked the clutch cylinder itself ?? I don't know if the Stelvio has the same neat extended bleed hose arrangement as the GRiSO.

It has the same bleed setup, I dont think the thread tape will do anything iether once I thought about how it seats as you say.

i have been underneath, etc, With the location of the clutch cyclinder and the design of the frame its buried in there pretty good but I can see nothing like a leak and I can get a wrench on the bolts holding it to the gearbox and they are all snug. The fluid when I bled it this morning is clean but did get a more air out. It has sat all day now on centerstand and bars even and clutch action is normal still.

Have you removed the swingarm to grease the bearings yet? If not you should and this would be the ideal time to pull the slave cylinder and inspect it.

Problem is that it doesn't sound like a slave problem. (Scratching head.) If it doesn't present with a more severe problem it might be worth trying swaping out the master and slave as well as checking out the pushrod depth. I can send you a master and slave, (Hoses too if you want?) as a loaner if you'd like to try it.

Pete

Have not done the swingarm yet, was putting that off till winter as this winter I will have a space to work on it and be warm and take all the time I want. I dont have anymore multi day trips with it for the rest of the summer so I am not too urgent to do too much with it. Certainly nothing obvious as I have checked what everyone has suggested. I have never had a clutch system get air in it like this. Thinking back it seems when it sits overnight on its sidestand I notice the issue starting out in the morning, as everything warms up the issue goes away then repeats.
Is it possible water got into it and created air through heating up? Just a wild guess. The first three days of the trip was cold and rain. Water would have to enter at the master resevoir tho which I would guess unlikley but it wouldn"t take much I gather.