1st Time Out with MRE Lockup

[RacingJake]

Tonight i did my best 60fter 1.46, 330fter was a 4.15 and ET was 6.49 at 103 mph. I started out with 6 oem springs and bolt and nut only on each arm.

The bike still bogg at 7K launch so I removed 2 of the oem springs and ran with just 4 to see what would happen next. The bike still bogg alittle and at the end of the night my best times were what's above. The lockup still needs some more tuning with softer springs to let it slip at launch and I think it could run high 1.30 60fters.

The best part was the quick access cover, it made the job a piece of cake.

Bike ran strong except for a few mis-shifts but that's ok cause I got a race cut tranny just waiting to go in during the winter months.

 

[scotty]

Im thinking of running a lockup on my street bike. I supose if i set it to lock up at about 7K or so i could still drive normally on the street . wht are your thoughts Jake or anyone. I will also have a back cut tranney installed for sure. Im till trying to locate a wider swing arm. Not for a slick but just a wider street tire/tyre

 

[RacingJake]

I still have alot to learn about lockups, but for street use I'd just install one with 6 oem springs. On the top end you'll never have any clutch slippage again. It will act just like a regular clutch but you can tune it to your needs.

The best part is the clutch feel, your fingers are going to love it. It take less than 1/2 the effort to pull the lever in as before.

The lockup assy bolts to the inner basket so if the bike is standing still and in gear with the clutch lever pulled in the engine rpm can be 1K to 10K and the lockup is just sitting still. That's where the springs come in to provide the clamping force to allow the inner basket to slip and engage as you let the cluch lever out, once the bike in underway the lockup arms take over and provide the extra clamping force to prevent the clutch from slipping as you go hauling butt down the road.

If you like to tinker with things then a lockup is the ticket, it just takes alittle time to find that sweet spot where the bike and the rider is the happiest.

 

[Dink]

Do you have to change the clutch cover to install a "lock-up" ??
Dink

 

[RacingJake]

Most kits come with a clutch cover spacer and you have to removed the cover every time to adjust it. I bought a RBD quick access cover that you just remove six screws and the plate comes off. Its alot easy'er at the track and only take's a few minutes to make changes.

Jake

 

[scotty]

SPACER IS A DEFINITE ITEM. I WAS ALSO PLANING ON THE QUICK ACCESS COVER--Caps key

 

[Detman101]

Could you all please explain exactly what this "Lockup Clutch" does?
I get clutch slippage when I try to take off at 4-5k rpm from a stoplight.
It feels like the rear tire is spinning but its not. The engine revs but doesn't seem to catch until I've taken off slowly first. It's annoying.

thanks,
Dm of mD

 

[Hoomgar]

Could you all please explain exactly what this "Lockup Clutch" does?
I get clutch slippage when I try to take off at 4-5k rpm from a stoplight.
It feels like the rear tire is spinning but its not. The engine revs but doesn't seem to catch until I've taken off slowly first. It's annoying.

thanks,
Dm of mD

He lives! Where have you been hiding brother?

 

[lhanscom]

Could you all please explain exactly what this "Lockup Clutch" does?
I get clutch slippage when I try to take off at 4-5k rpm from a stoplight.
It feels like the rear tire is spinning but its not. The engine revs but doesn't seem to catch until I've taken off slowly first. It's annoying.

thanks,
Dm of mD

A lockup is a device that goes onto your clutch and has weighted arms that move when it spins, and push the clutch plates together, the faster it spins the harder it presses the plates. It's nice because you can run lighter springs, to ease the clutch lever action, you can set the spring tension so you just pop the clutch when drag racing, and the faster you go the more the plates grab. It's also nice for high horsepower motors so the clutch doesn't slip in the higher gears. I'd love to get one someday, it would be nice for the nitrous hit.

 

[RacingJake]

The lockup is mainly for drag racing where it allows the clutch to slip when launching at the line. It allows the engine to be in the upper powerband and you can pop the clutch without the motor bogging down. It will give you better 60 foot times compared to the oem clutch by allowing the cluch to slip. Think of it like a high stall torque converter in a race car.

Now to stop the clutch from spinning all the way down the track there is six arms that you can add or remove weights (nut, washers, bolt). As the inner basket starts to spin faster (rear wheel too) the arms are thrown outward applying more pressure to the clutch pressure plate and along with the springs pressure the clutch will lockup and you will have no slippage.

You can install soft to HD springs to allow the clutch to slip alittle, alot or not at all when taking off from a standing stop. Most racers run around 200 lbs total static spring pressure. I think oem clutch springs are around 340 lbs pressure total, so you can see less spring pressure mean more slip.

You add more or less weight to the arms to determine how fast you want the clutch to lockup, more weigh faster it will lockup, less weigh later it will lockup. I would guess that you would want the lockup to lockup around the 60ft mark or sooner.

It just take some time to find that sweet spot between the two.

If you are spinning your clutch at 4-5K sound like it's time for some new fiber's or springs. When the fiber's are worn to the point that the pressure plate cannot apply enough clamping force due to the pressure plate hits the stops or inner basket. A lockup would not fix that problem until fiber and plate thickness is restored.

I'm no expert at this time maybe by next year when I get a couple hundred runs with it.

Jake

 

[biker66]

I've been running a lockup clutch on the streets for three years now without a problem.
It's a dream having the soft standard springs, saves your left hand !
Yet the bike never hesitates when I open the throttles (140bhp:s)

I've found for street riding you can decrease the weights on the arms.
Right now I only have a nut and a bolt on three of the six arms, making it a dual stage lock up, works great.

There are some pictures on my site, see 'modifications/lock up'.

 

[rosco15]

dm

Bead blast the steels and put shims behind the springs. That should fix it. Jake, Somebody told me to use a mini recorder. It helped me out alot. I can hear the arms come in by the fall of the rpm.

 

[RacingJake]

Here's what I have, you can see the arms and it bolts right over the pressure plate;

My exhaust pipe would of hit my cover so I went with a RBD cover and it's alot easy'er except for the price. New ones go for 250 bucks.

 

[RacingJake]

I've been running a lockup clutch on the streets for three years now without a problem.
It's a dream having the soft standard springs, saves your left hand !
Yet the bike never hesitates when I open the throttles (140bhp:s)

I've found for street riding you can decrease the weights on the arms.
Right now I only have a nut and a bolt on three of the six arms, making it a dual stage lock up, works great.

There are some pictures on my site, see 'modifications/lock up'.

Hey Biker66 what springs are you running, I'm using only four springs rated at 57 pounds each for a static pressure of 228 pounds. I'm thinking of removing a few of the bolts and nuts too next time at the track.

Jake

 

[RacingJake]

dm

Bead blast the steels and put shims behind the springs. That should fix it. Jake, Somebody told me to use a mini recorder. It helped me out alot. I can hear the arms come in by the fall of the rpm.

That's a good idea Ryan I'll give it a try.

So when does your clutch lockup at the track, 60ft?? or close to the tree. I need a referance point.

You run in the 1.30's too??

Thanks Jake

 

[biker66]

Hey Biker66 what springs are you running, I'm using only four springs rated at 57 pounds each for a static pressure of 228 pounds. I'm thinking of removing a few of the bolts and nuts too next time at the track.

Jake

I use six standard springs.
As I do my riding on the streets there's been no need to fiddle with slipping.
My main purpose was to stop the abuse of my left hand with HD springs and extra plates
This way I get a soft standard clutch feeling, yet high power performance when the arms apply pressure.

If I go to a dragstrip again I might consider removing two springs...

 

[rosco15]

The arms bring the motor down right around the tree. I usually run around 1.46 or so. This weekend at IRP I was getting 1.41-1.42. I weigh 210. I figure that kills the 60'. You have to tinker and find a happy medium. First pass of the day I launch at 7200 so it doesn't bog. After that I can turn it down to 6800.

 

[RacingJake]

I'm at 225 naked and the bike just wacks back on the bars. If i slide back in the seat alittle the front end feels like it off the ground all the way down the track. I don't think I'm more than a few feet from the starting line when the clutch grab. It does launch harder now.

Sounds like were pretty close together with our bikes. I just need to get to 1/4 mile track.

Thanks
Jake

 

[lecroy]

I stumbled onto this today.....


http://oldskoolsuzuki.info/index.htm?patrick/articles/lockup_clutch_by_lee/index.htm~main

 

[Detman101]

Could you all please explain exactly what this "Lockup Clutch" does?
I get clutch slippage when I try to take off at 4-5k rpm from a stoplight.
It feels like the rear tire is spinning but its not. The engine revs but doesn't seem to catch until I've taken off slowly first. It's annoying.

thanks,
Dm of mD

He lives! Where have you been hiding brother?

Not hiding...but riding. FINALLY! I've been enjoying my ratbike on the roads and travelling all over the place.


Dm of mD