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Booster
04-04-2007, 07:35 PM
Passing on some info i saved from Lorcan's gpz 750 turbo site, thought it could be handy to some here.


You will need to alter some dimensions to suit whatever bike you use this on, if this isn't clear enough I can do some drawings. I might do that anyway and turn it into a "How to" if there is enough interest.

The main plate for the lockup is in 13mm aluminium. It is 133mm overall dia, and locates on the 5 clutch spring mounts via pillars which are 11.5mm deep to give the plate an air gap between itself and the pressure plate of 4.5mm. This is enough for the pressure plate to be disengaged when you pull in the clutch lever, but near enough for the arms to bear on the pressure plate without reaching the end of their travel.

The arms that carry the weights are 4.8mm thick steel. 33mm overall height, 13mm wide at the top of the "L" and 19mm wide at the bottom. They locate on a steel pin 15 x 4.8mm thick in a slot in the back of the plate 21mm x 4.8mm, the slot is less than the full depth of the plate but still allows the pin plenty of free movement. The slot is punched so that the pin cannot fall out (you can see the punch marks in the pics). The arm fits in a slot 29mm x 4.8mm which goes right through the plate. The pin is set 6mm in and up from the bottom left corner in the arm to the centre of the pin. The pins are set on a 100mm base circle around the plate.

You will also need a spacer for the clutch cover and a puller the same amount longer than stock as you make the spacer. Mine is 32mm but that isn't quite enough and required the clutch rod arm to be ground down slightly to clear the arms of the lockup.

http://www.streetfighters.com.au/forum/upload/25391247057429.jpeg

Booster
04-04-2007, 07:39 PM
http://www.streetfighters.com.au/forum/upload/25391247036567.jpeg

Booster
04-04-2007, 07:43 PM
http://www.streetfighters.com.au/forum/upload/4629097638512.jpeg

Booster
04-04-2007, 07:44 PM
http://www.streetfighters.com.au/forum/upload/46290976324717.jpeg

Booster
04-04-2007, 07:45 PM
http://www.streetfighters.com.au/forum/upload/46290976336202.jpeg

Booster
04-04-2007, 07:47 PM
http://www.streetfighters.com.au/forum/upload/46290976324813.jpeg

Booster
04-04-2007, 07:49 PM
http://www.streetfighters.com.au/forum/upload/46290976345317.jpg

Booster
04-04-2007, 07:52 PM
i also have some drawings (DWG) of various parts of this assembly i can email to anyone interested.

catchmeifyoucan
04-04-2007, 07:56 PM
please explain?? what is a lock up clutch, and why is it good??

Tony Nitrous
04-04-2007, 08:06 PM
quote:Originally posted by catchmeifyoucan

please explain?? what is a lock up clutch, and why is it good??


Certrefugal? forces push the weights / arms out as the rev's go up.
Arms put more pressure on the plates.

Great for Top speed runs or if your changing up with an air shifter
on the strip.

Booster
04-04-2007, 08:07 PM
also if springs just don't have enough pressure without Arnie operating the clutch lever.

Benz
04-04-2007, 08:13 PM
The faster your clutch assembly spins, the more outward force is placed apon the bobweights situated on the "L" arms, which in turn force the clutch plates together, giving greater grip, therefore less slip. Perfect for turbo'd bikes that come on to power hard and fast. Good for setting up a drag bike with soft springs for a "gentle" launch, but as revs rise, you get much greater than normal grip from your clutch, usually resulting in higher top speeds.
As stated, you will need to extend your clutch cover with a spacer, and depending what sort of actuation your clutch has, you may need to either extend the rod, or make the puller longer to allow for the extra depth of the lockup
Or something like that.

catchmeifyoucan
04-04-2007, 08:17 PM
cheers for the explenation, makes sense now... cheers...

ozkat
04-04-2007, 08:18 PM
Ive done a few measurements and "Deano's" windowed clutch covers will work perfectly on a 1127 with lockup.... i think.