1098 SF clutch and brake lever overhaul.

Gimlet

Gimlet

Elite Member
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I want to replace the handlebar fluid reservoirs on my SF. The lids have gone all flakey and I've never liked the tupperware-look plastic reservoirs.
As my bike has a tuned engine the clutch has been uprated. The lever action was pretty heavy stock but it's heavier still now, so while I'm at it I want to improve the lever action as well as the looks.

I'm just confused about the options. I've looked on Conquest's website. There are integrated matching clutch and brake reservoir/lever/master cylinder kits from both Moto Corsa and AEM Factory. The Moto Corsas are a lot more expensive. And there are two options from AEM but I'm not sure what the difference is between the two.

First question is, will replacing the entire mastercyclinder affect the lever action - ie. lighten it? Or is it just a cosmetic exercise?

Second question is, I know I will need to replace the clutch slave, but which one and what size to lighten the lever action?

Ta.
 
Oberon slave, have always lightened Ducati clutch action, It may well be that is all that's needed with the flushing of the old fluid and bleeding.
The Brembo masters should be well up the job, so just the cosmetic pref of levers and reservoirs Jim (y)
 
Gimlet said:
Stainless Barnett basket and heavier springs.
Click to expand...
As Bob said.
You could always install lighter springs or even try removing some springs. If there are 6 remove 2. If the clutch slips under max acceleration (which I doubt it will) pit them back.
The basket isn’t making any difference to the clutch action it’s just the stronger springs doing that.
 
BobTheBounder said:
Oberon slave, have always lightened Ducati clutch action, It may well be that is all that's needed with the flushing of the old fluid and bleeding.
The Brembo masters should be well up the job, so just the cosmetic pref of levers and reservoirs Jim (y)
Click to expand...
Thanks Bob. I've used Oberson slaves on KTMs for years. Usually the first mod I've done. Think I'll get a set of their levers as well.

I could just replace the reservoir lids. I see Oberon do a set of those too. But it would be nice to have some CNC reservoirs to replace the sandwichbox plastic things. Integrated reservoir and MC would look vastly better than the wobbly bracket and little tube but it's a lot of money if there's no performance or lever action benefit.
 
West Cork Paul said:
As Bob said.
You could always install lighter springs or even try removing some springs. If there are 6 remove 2. If the clutch slips under max acceleration (which I doubt it will) pit them back.
The basket isn’t making any difference to the clutch action it’s just the stronger springs doing that.
Click to expand...
The clutch is as set up and reccommended by Rich Lewellyn at Louigi Moto. I'm inclined to leave it alone. But the levers, MC and slave are all stock. I think a lot of improvement would come from reducing the lever span.
I've got great faith in Oberon products from my KTM experience. I need a new clutch lever for my 1190 as ut happens. The adjuster has broken and the lever is stuck at maximum span. It's also a straight, not cranked lever. So although the action is light it strains the hand.

I think I'll go with levers and slave and see how that improves things.
As above, I'd really like integrated reservoirs and MC because it looks so much better. The AEM items sold by Conquest are less than half the price of Moto Corsa. Whether that's a reflection of their quality or the premium you're paying for the Moto Corsa name, I don't know.
 
This may help

IMG_2933.webp
 
West Cork Paul said:
As Bob said.
You could always install lighter springs or even try removing some springs. If there are 6 remove 2. If the clutch slips under max acceleration (which I doubt it will) pit them back.
The basket isn’t making any difference to the clutch action it’s just the stronger springs doing that.
Click to expand...
The stainless basket (actually stainless tipped fingers) is to prolong clutch life. The stock clutch basket was shot at 15K miles and the engine work I've had done accelerated the wear. The fingers had become grooved and I was getting chatter and grabbiness. No slip but the grabbiness would increase wear on the friction plates.

The only drawback with the Barnett basket is the dry clutch rattle is louder than ever. Sounds like a load of spanners being shaken in a tin can. So I haven't fitted an open clutch cover as the stock one is insulated to reduce the noise. I would like to replace it though as I don't like the gold colour. Doesn't fit in with the rest of the bike somehow. I thought of a carbon cover but they're not insulated and will be as loud as an open cover.
 
Markduc said:
This may help

View attachment 132985
Click to expand...
I'd be interested to know the piston size of the Oberon slave piston looking at that. It doesn't say on their website. The KTM Oberon slaves didn't lighten the lever action but it wasn't heavy to start with, it's just that stock KTM clutch slaves are notoriously crap and prone to leaking.

However if Oberon Ducati slaves are known to lighten lever action on Ducs, that's where I'll start. They do make that claim on their website so I'm assuming the piston is larger than stock.
 
Gimlet said:
The stainless basket (actually stainless tipped fingers) is to prolong clutch life. The stock clutch basket was shot at 15K miles and the engine work I've had done accelerated the wear. The fingers had become grooved and I was getting chatter and grabbiness. No slip but the grabbiness would increase wear on the friction plates.
Click to expand...
As its steel it will last a lot longer before indentations/grooves caused by the tangs on the friction plate begin to appear. The stock basket is a much softer aluminium alloy (as is the metal base material on the friction plates) and this wears much quicker. It has to be quite severely grooved though for the plates to actually get stuck in the grooves.

There are 2 wear measurements on the friction plates, the thickness of the friction material and the gap between the edge of the tangs and the basket fingers.

The former starts at 3mm and shouldn’t fall below 2.6mm.

The latter shouldn’t be less than 0.6mm ie 0.3mm each side.

It’s the latter measurement that’s crucial for a quieter clutch, less room to move, less slap, less rattly noise.

Most owners, who don’t check these things themselves (and even those who do), go far beyond the recommended wear limits, especially on the latter measurement 😕.


Gimlet said:
I'd be interested to know the piston size of the Oberon slave piston looking at that. It doesn't say on their website.
Click to expand...
It’s 29mm according to the useful chart Markduc posted, giving a 37% reduction in pull force.
 
West Cork Paul said:
As its steel it will last a lot longer before indentations/grooves caused by the tangs on the friction plate begin to appear. The stock basket is a much softer aluminium alloy (as is the metal base material on the friction plates) and this wears much quicker. It has to be quite severely grooved though for the plates to actually get stuck in the grooves.

There are 2 wear measurements on the friction plates, the thickness of the friction material and the gap between the edge of the tangs and the basket fingers.

The former starts at 3mm and shouldn’t fall below 2.6mm.

The latter shouldn’t be less than 0.6mm ie 0.3mm each side.

It’s the latter measurement that’s crucial for a quieter clutch, less room to move, less slap, less rattly noise.
Click to expand...
It will be interesting to check the tang clearances. The clutch is virtually brand new as it was fitted only about 1500 miles before the front piston cracked and the bike got mothballed.
As Rich Lewellyn fitted the clutch I imagine it will be spot-on but I will definitely be keeping a check on it.
I'd like it to last as long as possible as it wasn't cheap.
 
Gimlet said:
The clutch is as set up and reccommended by Rich Lewellyn at Louigi Moto. I'm inclined to leave it alone. But the levers, MC and slave are all stock. I think a lot of improvement would come from reducing the lever span.
I've got great faith in Oberon products from my KTM experience. I need a new clutch lever for my 1190 as ut happens. The adjuster has broken and the lever is stuck at maximum span. It's also a straight, not cranked lever. So although the action is light it strains the hand.

I think I'll go with levers and slave and see how that improves things.
As above, I'd really like integrated reservoirs and MC because it looks so much better. The AEM items sold by Conquest are less than half the price of Moto Corsa. Whether that's a reflection of their quality or the premium you're paying for the Moto Corsa name, I don't know.
Click to expand...
I’ve got these on one of my 1098R’s, they’re lovely 🥰


IMG_4075.webp
 
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