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Hydraulic Bike Clutch
locoboy - 6/11/04 at 11:34 AM

Hi Guys,

I have a CBR1000 engine which has a Hydraulic clutch, i bought this M/C at Donnington for a fiver!

Does anyone have any idea if it will be any use or not?

MikeR - 6/11/04 at 01:10 PM

Doesn't it all depends on the bore + stroke of the master cyclinder (ie fulid displaced) and bore / stroke of the slave cylinder.........

At a guess, bike clutches are hand driven off the handlebars so small, therefore small displacement. Thats got 5/8 written on the side of it so ....... probably large displacement.

(p.s. no idea what i'm talking about)

Peteff - 6/11/04 at 01:57 PM

I'd give it a try, it's not that big. You can experiment by moving the point you connect to on the pedal to limit the travel. I have read of bike rear brake master cylinders being used for the job if it is too big.

phelpsa - 6/11/04 at 11:08 PM

The MC on my gixer 1100 clutch system is 1/2", which is standard size for motorcycles I believe (I think they are mostly the same make aswell).

Adam

Hugh Jarce - 7/11/04 at 01:33 AM

quote:
Originally posted by phelpsa
The MC on my gixer 1100 clutch system is 1/2", which is standard size for motorcycles I believe (I think they are mostly the same make aswell).

Adam

I can't think of any M/C clutch master cylinder that isn't 12mm (.4724".
colmaccoll, if you use that (very nice looking) master cylinder, then you will need to alter your pedal ratio to suit. Don't forget to fit a mechanical stop as well, as the bike cylinders have a very small capacity and the fluid from that gert cylinder could displace/cause damage to the slave cylinder.

locoboy - 7/11/04 at 05:21 PM

am i right in thinking then that i should just establish how much travel is required to fully open the clutch then fit a mechanical stop?

Does anyone know what sort of thread is most likely to be on the outlet from this type of MC?

phelpsa - 7/11/04 at 05:31 PM

Mine definately says 1/2" and it is the same as is used on the cbr1000, hayabusa, older CBR600 and a lot more as they have the same code from the bike shop we bought it from.

Anyway, maybe they changed from 1/2" to 12mm because there is a very small difference

locoboy - 7/11/04 at 05:34 PM

Adam,

Is that the bar mounted MC your talking about?

phelpsa - 7/11/04 at 05:40 PM

Yep, we are making a stick mounted setup.

Adam

locoboy - 7/11/04 at 05:49 PM

has anyone used the bar mounted MC with a foot operated pedal?

Pictures would be fantastic!

Also, is it an easy job or is there a kit to convert it to a manual clutch?

Hugh Jarce - 7/11/04 at 08:07 PM

quote:
Originally posted by colmaccoll
Does anyone know what sort of thread is most likely to be on the outlet from this type of MC?

As it's an imperial cylinder, it will be either 3/8" UNF or 7/16" UNF; both sizes are used in imperial cylinders.


quote:
Originally posted by phelpsa
Mine definately says 1/2" and it is the same as is used on the cbr1000, hayabusa, older CBR600 and a lot more as they have the same code from the bike shop we bought it from.

Anyway, maybe they changed from 1/2" to 12mm because there is a very small difference

Actually, there are a couple of bikes now using the imperial equivalent bore sizes. Rather odd really; going backwards. They were always traditionally 12mm, 14mm and 16mm.

Kissy - 8/11/04 at 01:27 PM

I have a CBR1000 engined locost, just about to MOT it. I note you say 'stick mounted' I assume by that you will mount on to the gear change lever? I have CBR1000 master cylinder/lever which is your for a small consideration. I fitted a pedal operated clutch (purely because I did not have the bike item at the time), I used a Nissan clutch cylinder, which if anything could do with being larger bore, as I have a fairly long pedal travel. Remember there are differences between a handlebar mounted and pedal clutches,like how much force your foot can generate + the pedal ratio + what is the bore on the slave cylinder?
I'll post some pics soon.