Oberon clutch setup

[bang76]

So Ive installed an Oberon 29mm piston clutch slave. Master is standard 13mm.
I know that the clutch spring plate stroke will get shorter with a larger diametre slave. But mines only moving 1.6mm resulting in a somewhat half "sticky" clutch.
Anyone know the stroke length you get on the clutch spring plate with this setup ? Or is that whats expected ? Just air in the system ?

[wobblyas]

Originally Posted by bang76

So Ive installed an Oberon 29mm piston clutch slave. Master is standard 13mm.
I know that the clutch spring plate stroke will get shorter with a larger diametre slave. But mines only moving 1.6mm resulting in a somewhat half "sticky" clutch.
Anyone know the stroke length you get on the clutch spring plate with this setup ? Or is that whats expected ? Just air in the system ?

I have installed lots of the Oberon slave cylinders and have never noticed a discernible change in the plate movement or the engagement point for the clutch lever. I would double check that you have not introduced any air into the clutch hydraulics. Note also Oberon ship their clutch slave cylinders with a short extension pin that is required on some models of bike. The instructions detail on what years of bike that you need to fit this.

From trial and experimentation I have found that the best clutch stack height for the Supersports fitted with the Oberon master cylinders is 39mm but they seem to be just as tolerant as the standard master cylinders of stack height variation.

There are several other things that can cause stick clutches on these bikes and make it difficult to engage neutral. Make sure that your clutch basket is not too badly notched, make sure the steel plates in your stack are not warped (no more than 0.2mm) and also check the condition of the cush drives in your hub. When the cust drivers are knackered they cause the hubs to run eccentric and this causes the clutch to not be smooth. When I encounter this issue I change the hubs to lightweight aftermarket ones that don't have cush drives.

[DME3]

You might have forgotten to install the extra thingie that's needed for models with the older, shorter push rod

[bang76]

Originally Posted by DME3

You might have forgotten to install the extra thingie that's needed for models with the older, shorter push rod

The small shaft extension is installed

[bang76]

Originally Posted by wobblyas

I have installed lots of the Oberon slave cylinders and have never noticed a discernible change in the plate movement or the engagement point for the clutch lever. I would double check that you have not introduced any air into the clutch hydraulics. Note also Oberon ship their clutch slave cylinders with a short extension pin that is required on some models of bike. The instructions detail on what years of bike that you need to fit this.

From trial and experimentation I have found that the best clutch stack height for the Supersports fitted with the Oberon master cylinders is 39mm but they seem to be just as tolerant as the standard master cylinders of stack height variation.

There are several other things that can cause stick clutches on these bikes and make it difficult to engage neutral. Make sure that your clutch basket is not too badly notched, make sure the steel plates in your stack are not warped (no more than 0.2mm) and also check the condition of the cush drives in your hub. When the cust drivers are knackered they cause the hubs to run eccentric and this causes the clutch to not be smooth. When I encounter this issue I change the hubs to lightweight aftermarket ones that don't have cush drives.

Ill try to measure and check the stack height. Just thought that the stroke lenght would be the same thatever the stack height is?
Ill take it apart and get wiser on the mechanics of the clutch

[bananaboat]

Originally Posted by bang76

Ill try to measure and check the stack height. Just thought that the stroke lenght would be the same thatever the stack height is?
Ill take it apart and get wiser on the mechanics of the clutch

My bet is that you just need to bleed the system. When I swapped mine out, I thought I was super careful, did a quick bleed on the slave side, but still the clutch would not completely disengage, and I couldn't get into neutral - typical if the clutch won't disengage completely. I installed a bleeder bolt at the master end, flushed and bled the system and it was perfect.

hope that gets you on the road.

[bang76]

Originally Posted by bananaboat

My bet is that you just need to bleed the system. When I swapped mine out, I thought I was super careful, did a quick bleed on the slave side, but still the clutch would not completely disengage, and I couldn't get into neutral - typical if the clutch won't disengage completely. I installed a bleeder bolt at the master end, flushed and bled the system and it was perfect.

hope that gets you on the road.

Thread update:
Thought I had bled the fluid enough when I had this issue. However, I bought and bled the clutch with an air driven brake bleeder and now the clutch works 10 times better !
- so its better to get a "blow" instead of a "hand job"