TOPIC:

Does anyone have experience with using a lock-up clutch on the street? If I remember correctly, the clutch can't be pulled in above a certain RPM. I'm thinking about adding one to my KZ but it will be mostly for the street, so I'm not sure.
Thanks

Lots of people have put lock up's on street bikes and they work just fine.It's sliders that don't work on street bikes ,rev controlled centrifigal clutch ( think snowmobile) that doesn't disengage until a the low side rev setting is reached backing off the throttle.After that the motor freewheels.

Agree with Jack, you can use a lockup on the street no problem at all. The name "lockup" is a bit misleading, it doesn't "lock" anything, all it does is add to the the spring pressure.

Note that you will read elsewhere that the lockup action is entirely dependent on rear wheel speed. This is quite misleading, it doesn't lock up any harder in 5th gear than it does in 1st. Rear wheel speed plays a part, but mostly it's dependent on RPM.

I have run one on the street for two years and no problems at all. The biggest thing is to not to add too much weight and break the clutch discs. I played around and added just enough weight so it would not slip. Also there are shims that you can add to adjust spring pressure also. After you get it set to the right combination it is a very nice setup.

Lockups are entirely dependent on read wheel speed. The lock up hat is on top of the pressure plate / inner hub. This doesn't turn if the bike is sitting still no matter how high you rev the engine.

The inner hub only turn as the rear wheel does. The faster the wheel turns the faster the inner hub turns which slings out the centrifugal arms applying more pressure to the top of the pressure plate.

Only a slider clutch which is connected to the outer clutch basket is RPM sensitive.

Jay

APE Jay wrote:

Lockups are entirely dependent on read wheel speed. The lock up hat is on top of the pressure plate / inner hub. This doesn't turn if the bike is sitting still no matter how high you rev the engine.

The inner hub only turn as the rear wheel does. The faster the wheel turns the faster the inner hub turns which slings out the centrifugal arms applying more pressure to the top of the pressure plate.

Only a slider clutch which is connected to the outer clutch basket is RPM sensitive.

Jay

I never thought of it that way, but that really makes sense. I guess my original question was a bit fuzzy. I am wondering if, for example, you are at the end of the quarter mile in top gear, rpm's at the redline, can you pull in the clutch or do you have to wait until the bike slows down?? What if you're on the freeway at 80 mph? Can you disengage the clutch?

This would probably depend on how much weight you had on the arms. That is what you will be trying to overcome when you pull in the lever.

I don't see why you would need a lockup on a street bike. We have always recommended against it for safety reasons, such as what you mentioned.

A 10 plate clutch should easly be able to handle anything that can be street driven.

Jay

Jay, per your description would it not be more accurate to say that lockup depends on trans input shaft speed?

Seems to me that it would be rpm dependent and not based on rear wheel speed. The rear wheel is going to turn an awful lot faster for the same input shaft speed in high gear than it will in first, yet the clutch would lock up at the same rpm in each gear.

I have no experience or knowledge of the subject, this is just based on Jay's description of how it works,

steell wrote:

Jay, per your description would it not be more accurate to say that lockup depends on trans input shaft speed?

Seems to me that it would be rpm dependent and not based on rear wheel speed. The rear wheel is going to turn an awful lot faster for the same input shaft speed in high gear than it will in first, yet the clutch would lock up at the same rpm in each gear.

I have no experience or knowledge of the subject, this is just based on Jay's description of how it works,

That says it better.

Lorcan wrote:

Note that you will read elsewhere that the lockup action is entirely dependent on rear wheel speed.

APE Jay wrote:

Lockups are entirely dependent on rear wheel speed.

I have psychic powers...

APE Jay wrote:

This would probably depend on how much weight you had on the arms. That is what you will be trying to overcome when you pull in the lever.

I don't see why you would need a lockup on a street bike. We have always recommended against it for safety reasons, such as what you mentioned.

A 10 plate clutch should easly be able to handle anything that can be street driven.

Jay

Okay- all that makes sense to me- now how does a road racing slipper clutch work- the type they consider "traction control"

A stock Z clutch will easily handle 100+ hp even in a dragrace application so a lock-up would only be a waste of money and hp. A good setup is stock plates with inner valve springs for clutch springs with a bearing clutch pusher.