Lets talk about scrub brakes

[ChromeBikeGuy]

I'm working on this old bike for my grandson. He is 8 and will ne his first mini bike. How effective will it be? Its getting a 3.5 Honda and a clutch band brake also.
What do I put on the plate? More steel, rubber, something else?
Give me the good, the bad, the ugly. Is it going to stop or should I invest in extra shoes and teach him to drag his feet?
I searched for a minute and didn't see much discussion of the usefulness of scrub brakes.

 

[mustangfrank]

I'm working on this old bike for my grandson. He is 8 and will ne his first mini bike. How effective will it be? Its getting a 3.5 Honda and a clutch band brake also.
What do I put on the plate? More steel, rubber, something else?
Give me the good, the bad, the ugly. Is it going to stop or should I invest in extra shoes and teach him to drag his feet?
I searched for a minute and didn't see much discussion of the usefulness of scrub brakes.

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Clutch brakes are very effective but you have the "chain breaks - no brakes" debate there to consider. Some of the scrub brakes had a steel or aluminum wear shoe but they lose effectiveness when the tire gets wet. If it's for a young kid spend the time to install front and rear wheel brakes and don't think twice.

I like having good brakes available but I hardly ever use them, plan ahead, learn to coast...then again I'm 50 something.

 

[SAT]

I'm working on this old bike for my grandson. He is 8 and will ne his first mini bike. How effective will it be? Its getting a 3.5 Honda and a clutch band brake also.
What do I put on the plate? More steel, rubber, something else?
Give me the good, the bad, the ugly. Is it going to stop or should I invest in extra shoes and teach him to drag his feet?
I searched for a minute and didn't see much discussion of the usefulness of scrub brakes.

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Our Sears Runabout has a cast aluminum pot metal scrub brake that works. The casting is curved to match the rear tire profile. We added a clutch brake, and RLV gold-on-gold chain, to reduce the thrown/broke chain event. You will probably have to make a facsimile out of aluminum, cause they are like hen’s teeth. Good project.

 

[desert rat]

All right I will get in on this one. If it was mine I would run a clutch band and a rub brake as well. For the rub brake I would find a piece of tire tread off the side of the road( big trucks toss them all the time) and cut it to fit the shoe plate. You have four bolt holes to attach it with just counter sink the heads. you will have very good stopping power and a positive back up with the scrub brake. just my two cents. I would also repair that 90 deg plate on the rear of the motor plate. bend it back up and fill in the hole that was cut in . That was there to stiffin the motor plate . The way it is now your motor will "wiggle" more than if the 90 was intact. you will have a nice rider with just a little time and work. I see from the back ground you don't have a problem getting greasy so you will do just fine.

 

[toomanytoys]

You guys are over thinking. I got my first bike younger than 8. Manco streaker 3.5hp tecumseh with a steel scrub brake. Rode that thing for many hours all over the fields and trails on our property.

I never couldn't stop. The only time it wasn't as effective is when there was dew on the grass but even then it would stop just took a bit more pressure.

 

[desert rat]

You guys are over thinking. I got my first bike younger than 8. Manco streaker 3.5hp tecumseh with a steel scrub brake. Rode that thing for many hours all over the fields and trails on our property.

I never couldn't stop. The only time it wasn't as effective is when there was dew on the grass but even then it would stop just took a bit more pressure.

We had strait up scrubs,,,,,I know.The holes in this one tells me "something" was mounted. Remember" WE" are miles away and" I" would do. To OP get wheels and tires. motor/ clutch, Muck it up then we get tighter and better. We will all help you along the way. Kids and band aids aint no thing just be home before the street lights come on.

 

[ChromeBikeGuy]

It's done. The grandson is loving it. I had to weld a block on the scrub brake bar or he couldn't push it down far enough for it to work.

 

[desert rat]

Good job ,looks good. But I got a question where is he putting his right foot when he is riding?

 

[SAT]

It's done. The grandson is loving it. I had to weld a block on the scrub brake bar or he couldn't push it down far enough for it to work.
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If more braking is needed, you can use an angle cut-off wheel to make grooves in the surface of the scrub plate. Not deep, but frequent. It helped some on our Manco Streaker, especially when it was wet.

 

[loworange88]

Cool. I added a clutch brake to our old Sears MB. I used a handle bar brake lever to actuate the clutch brake as the "main brake". The original scrub brake and a new foot pedal are the "back up" brake. in addition to the aluminum shoe, I added a thick piece of rubber to the aluminum shoe face. I sanded the aluminum and glued it on, then added 2 small thru holes and added small screws and nuts to ensure the hold of the rubber. Its definately a wear item, but it will lock the rear wheel right up. Once the rubber wears out, I cut a new piece and replace it.

 

[Harquebus]

Good job, looks good. But I got a question where is he putting his right foot when he is riding?

Bingo! Looks like the grandson is "riding the brake" at all times. Not good.

Those foot pegs look extremely low budget too. I'd have done tubes with rubber covers or something more substantial with grip.

Dontcha just love it when a fella has a project/basket case on his first post of the thread, and when he posts again, it's all done and already being ridden? Pffft, this guy had it all figured out. Didn't need any more help /s.....

 

[desert rat]

I wish I was that quick. Mabey if I had just one, right?

 

[ChromeBikeGuy]

Bingo! Looks like the grandson is "riding the brake" at all times. Not good.

Those foot pegs look extremely low budget too. I'd have done tubes with rubber covers or something more substantial with grip.

Dontcha just love it when a fella has a project/basket case on his first post of the thread, and when he posts again, it's all done and already being ridden? Pffft, this guy had it all figured out. Didn't need any more help /s.....

I just didn't post any build pics. The point of this thread was to talk about the scrub brakes. Not much room to do anything different on this bike, so wanted to discuss them. End result, they work fine, for an 8 year old on a 3.5 Honda motor.