Downshifts getting herder when engine warms up

[PieEater]

Hi Fokkers - bike has done just over 60,000 miles and downshifts are starting to get harder to engage. I've adjusted the clutch cable from the top adjuster so there is some but very little slack, I've also adjusted the lever span outwards so the cable is being pulled in a bit more. Is it time to replace the clutch or is there something else I should be looking at first?

[agricola]

Always best to start with the cheapest option first if youre not certain its the clutch plates etc. Try a new cable.

[Trebus]

Might be worth greasing up the rose joints on the shift mechanism. There were some problems reported with the blanking plug falling out at then end of the main shaft causing oil starvation issues. 

Possibly some wear in the basket fingers which much need dressing.

That’s where I’d start after ruling out the cable.

[Gnasher]

Check both ends of the cable for Adjustment/cable operation/wear or damage, if all is well you'll need to go deeper. 

First check the clutch push/pull rod bearings, the top one can be done without removing the clutch cover.  If there's any play it's buggered and will need replacing, fairly common on bikes 30k plus.  The seal starts to degrad and water/crud get in, likelyhood is the bottom is ok as it's inside the casing but check it.  The mechanism only moves a few mm at the bottom, if the top bearing is shot it will not release the plates properly. Giving you hard gear changes.

If that's all ok than check the ends of the push/rod for wear and then it's the plates, basket.  Chances are it's at worst the top bearing.

If all of the above is good then you're looking at worn possibly damaged selector mechanism or dogs.

[PieEater]

Thanks guys, appreciate the advice, this will be my winter project !!

[b1k3rdude]

I added stainless springs on the clutch end of the cable on mine, 

There is already a spring on the clutch shaft arm (you can see it in the photo) that performs this function?, so your mod may potentially be masking that there is an issue with your cable? and making the lever harder to pull.

[PieEater]

I'm also thinking that because it only happens when the engine warms up (15+ miles) there must be a part that is expanding with the heat whilst another part isn't expanding as much in order to not fully engage the clutch, so not sure what that would be !?! Looking at Google a motorcycle clutch generally lasts 50k at most and my bikes done 64k so I'm thinking of getting a clutch kit and filing down any grooves in the basket before refitting as well as replacing the top actuator bearing. Does that sound like a plan?