Oil causing clutch slip

baz

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What engine oil cause's the least amount of clutch slip ?
I've read synthetic oil can cause clutch slip but do all engine oils?
I have a BSA b50 so the clutch shares the engine oil overwise I'd be using ATF
Cheers
 

ashman

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Most motorcycle oils are designed for wet clutches, if you use normal motor oil your clutch will slip.
 

ashman

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Yes but which motorcycle oil?
How long is a piece of string, most modern MC oils are pretty good but being a older bike maybe one with a higher zinc level as I only have my old Norton and my modern Thruxton to contend with as well my Honda dirt bike.
 

KiwiShane

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What engine oil cause's the least amount of clutch slip ?
I've read synthetic oil can cause clutch slip but do all engine oils?
I have a BSA b50 so the clutch shares the engine oil overwise I'd be using ATF
Cheers
Kind of stuck between a rock n a hard place....for what's good for the motor..but maybe not so good for c/plates..(not a BSA expert or any):)
Check/measure clutch pack ..maybe room for another plate.. or heavier springs .. check out using a high zinc 10w/40 mineral oil ...
Got offered a BBD44 the other day was once owned by Hugh Anderson (NZ) needed a clean up but too pricey for me...but bloody nice..
 

baz

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Kind of stuck between a rock n a hard place....for what's good for the motor..but maybe not so good for c/plates..
Check/measure clutch pack ..maybe room for another plate.. or heavier springs .. check out using a high zinc 10w/40 mineral oil ...
Got offered a BBD44 the other day was once owned by Hugh Anderson (NZ) needed a clean up but too pricey for me...but bloody nice..
I have an extra plate
I've hand decked all the plates plain and new friction plates
Springs are wound right in
These things have worked for me in the past on a b44 and a big bore t15 but of course they have a separate chaincase
I have a new set of springs on the way
These clutches are always a pain because they are so small
I just need a recommendation on a less slippery oil I reckon
I'm currently using Morris golden film 20/50
 

KiwiShane

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I have an extra plate
I've hand decked all the plates plain and new friction plates
Springs are wound right in
These things have worked for me in the past on a b44 and a big bore t15 but of course they have a separate chaincase
I have a new set of springs on the way
These clutches are always a pain because they are so small
I just need a recommendation on a less slippery oil I reckon
I'm currently using Morris golden film 20/50
All I know is when that ep90 used to get through to the clutch via the mainshaft after a while the commando clutch was crap..lol....when that happened I watched a mate drop the primary oil out of his commando...put the bike on its timing side pour in a good amount of kerosene into the clutch basket ...stand it up and get it running while pulling the clutch in and out...drain out the primary while tipped over on the primary side...tip some oil back in and away he would go.....not reccomended for B50
 

baz

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All I know is when that ep90 used to get through to the clutch via the mainshaft after a while the commando clutch was crap..lol....when that happened I watched a mate drop the primary oil out of his commando...put the bike on its timing side pour in a good amount of kerosene into the clutch basket ...stand it up and get it running while pulling the clutch in and out...drain out the primary while tipped over on the primary side...tip some oil back in and away he would go.....not reccomended for B50
Yep I've heard of people putting petrol in the chaincase to wash the clutch plates!!!
 

KiwiShane

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Yep I've heard of people putting petrol in the chaincase to wash the clutch plates!!!
Well that would clean the clutch out quick...but not my style...there has been a couple of B441's & B50's sell in little ol new zealand lately
 

Fast Eddie

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I would suggest you look for an oil that is labelled thus:

JASO MA or JASO MA2

If you’re looking for a the best synthetic oil you can find, Bel Ray V twin synthetic was one of the top scoring wet clutch friendly oils in Comnoz’ epic oil test.
 

baz

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I would suggest you look for an oil that is labelled thus:

JASO MA or JASO MA2

If you’re looking for a the best synthetic oil you can find, Bel Ray V twin synthetic was one of the top scoring wet clutch friendly oils in Comnoz’ epic oil test.
I have managed to sort it now
When I stripped the clutch I found there was barely any oil on the plates
I removed the cork from the back of the first plate to allow clearance and added an extra friction plate and an extra plain plate
No more slipping
I was out on it last night and as I was coming off a roundabout i nearly got taken out by an oncoming Mercedes overtaking a car he was on my side of the road
My side of the bollard
He went the wrong way around the roundabout!!!!
 
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He went the wrong way around the roundabout!!!!
Roundabouts are weird enough on a motorcycle, but that is a first. :oops:

I use 0-20 synthetic in the primary case of a hot rodded 750 N-Word. No clutch slip, but it's a different bike and clutch, and I use a 1/4" gap at the lever. I stopped using ATF in the primary. Only advantage of red ATF is you know where the leak is coming from. lol
 
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baz

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Roundabouts are weird enough on a motorcycle, but that is a first. :oops:

I use 0-20 synthetic in the primary case of a hot rodded 750 N-Word. No clutch slip, but it's a different bike and clutch, and I use a 1/4" gap at the lever. I stopped using ATF in the primary. Only advantage of red ATF is you know where the leak is coming from. lol
The b50 shares the engine oil in the primary unfortunately
And you can't easily fit an oil seal
The oil appears to stay out of the clutch basket to a good degree
Just the chain dips in the oil and the oil height is kept level by the vent hole
I should add that when the car was on my side of the road I panic braked
I locked the front wheel up
The bars went full lock left
I released the brake and the bike straightened up
I got between the car and pavement
I use this road every day for work and I look at that part of the road and can't believe I got through!!
 

KiwiShane

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The b50 shares the engine oil in the primary unfortunately
And you can't easily fit an oil seal
The oil appears to stay out of the clutch basket to a good degree
Just the chain
The b50 shares the engine oil in the primary unfortunately
And you can't easily fit an oil seal
The oil appears to stay out of the clutch basket to a good degree
Just the chain dips in the oil and the oil height is kept level by the vent hole
I should add that when the car was on my side of the road I panic braked
I locked the front wheel up
The bars went full lock left
I released the brake and the bike straightened up
I got between the car and pavement
I use this road every day for work and I look at that part of the road and can't believe I got through!!
Glad you got through and sorted both rock n hard places bro
 
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The b50 shares the engine oil in the primary unfortunately
And you can't easily fit an oil seal
The oil appears to stay out of the clutch basket to a good degree
Just the chain dips in the oil and the oil height is kept level by the vent hole
I should add that when the car was on my side of the road I panic braked
I locked the front wheel up
The bars went full lock left
I released the brake and the bike straightened up
I got between the car and pavement
I use this road every day for work and I look at that part of the road and can't believe I got through!!
Sorry about the useless thought on the oil.

Glad you made it through the gauntlet. Good timing on releasing the brake saved your butt. Experience matters.
 

baz

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Sorry about the useless thought on the oil.

Glad you made it through the gauntlet. Good timing on releasing the brake saved your butt. Experience matters.
It was just luck on this one I can assure you
 

KiwiShane

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Sorry about the useless thought on the oil.

Glad you made it through the gauntlet. Good timing on releasing the brake saved your butt. Experience matters.
I agree ...two things...Skill & Experience
 
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