Rear handbrake?

RandyS
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RandyS
Edited Date/Time 6/6/2020 2:49am
I think I might have asked this before but I can't remember getting an answer. Why aren't these teams building a small handbrake on the clutch side for right hand first turns? Is it not legal?
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lostboy819 6/3/2020 10:00pm
6/3/2020 10:00pm
This isnt the 250 nervous class at your local knobby way, these guys have mastered turning BOTH left and right, right hand first corner is no big deal. Cool
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RandyS
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RandyS 6/3/2020 10:04pm
6/3/2020 10:04pm
lostboy819 wrote:
This isnt the 250 nervous class at your local knobby way, these guys have mastered turning BOTH left and right, right hand first corner is no...
This isnt the 250 nervous class at your local knobby way, these guys have mastered turning BOTH left and right, right hand first corner is no big deal. Cool
Every rider out there would be faster if they had a way to lay into a right hand first corner. In a race for inches I'm just surprised it hasn't been done. It would be relatively simple to have a little lever like a hot start.
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PRM31
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PRM31 6/3/2020 10:10pm
6/3/2020 10:10pm
Some MotoGP guys use them.
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HusqFan3
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HusqFan3 6/3/2020 10:12pm
6/3/2020 10:12pm
RandyS wrote:
I think I might have asked this before but I can't remember getting an answer. Why aren't these teams building a small handbrake on the clutch...
I think I might have asked this before but I can't remember getting an answer. Why aren't these teams building a small handbrake on the clutch side for right hand first turns? Is it not legal?
I’m with you man. They should have a rear break lever, a button for quad jumps, and cruise control for optimal whoops speed. For the life of me i can’t figure out why they haven’t done this yet?
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FortyHat
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FortyHat 6/3/2020 10:18pm
6/3/2020 10:18pm
You do realize that you have to use the rear brake and the clutch at the same time very often right? Even in RH turns. So unless you are using an auto clutch, you got problems. SX and moto aren't like trail riding.
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MohMoto14
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MohMoto14 6/3/2020 11:35pm
6/3/2020 11:35pm
FortyHat wrote:
You do realize that you have to use the rear brake and the clutch at the same time very often right? Even in RH turns. So...
You do realize that you have to use the rear brake and the clutch at the same time very often right? Even in RH turns. So unless you are using an auto clutch, you got problems. SX and moto aren't like trail riding.
Learn control and stop locking your brakes weekend warrior.
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JBecker 72
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JBecker 72 6/4/2020 2:43am
6/4/2020 2:43am
lostboy819 wrote:
This isnt the 250 nervous class at your local knobby way, these guys have mastered turning BOTH left and right, right hand first corner is no...
This isnt the 250 nervous class at your local knobby way, these guys have mastered turning BOTH left and right, right hand first corner is no big deal. Cool
It’s a valid question since it’s used in other forms of motorcycle racing at the highest level.


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Tuna
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Tuna 6/4/2020 4:27am
6/4/2020 4:27am
FortyHat wrote:
You do realize that you have to use the rear brake and the clutch at the same time very often right? Even in RH turns. So...
You do realize that you have to use the rear brake and the clutch at the same time very often right? Even in RH turns. So unless you are using an auto clutch, you got problems. SX and moto aren't like trail riding.
MohMoto14 wrote:
Learn control and stop locking your brakes weekend warrior.
Ok there stud😂
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kkawboy14
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kkawboy14 6/4/2020 4:32am
6/4/2020 4:32am
They can use their brake in right hand turns, they are saying that because they ran out of mold/mole and woodpecker stories!
McG194
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McG194 6/4/2020 4:40am
6/4/2020 4:40am
lostboy819 wrote:
This isnt the 250 nervous class at your local knobby way, these guys have mastered turning BOTH left and right, right hand first corner is no...
This isnt the 250 nervous class at your local knobby way, these guys have mastered turning BOTH left and right, right hand first corner is no big deal. Cool
JBecker 72 wrote:
It’s a valid question since it’s used in other forms of motorcycle racing at the highest level. [img]https://p.vitalmx.com/photos/forums/2020/06/04/431049/s1200_C521223E_672E_4207_B1AF_6D55D5C4B31D.jpg[/img]
It’s a valid question since it’s used in other forms of motorcycle racing at the highest level.


Mick Doohan was the first to use it in GP because his leg was so jacked he couldn't pivot his ankle. I think it's a legit idea. Rekluse makes one already.
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Tuna
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Tuna 6/4/2020 5:27am
6/4/2020 5:27am
lostboy819 wrote:
This isnt the 250 nervous class at your local knobby way, these guys have mastered turning BOTH left and right, right hand first corner is no...
This isnt the 250 nervous class at your local knobby way, these guys have mastered turning BOTH left and right, right hand first corner is no big deal. Cool
JBecker 72 wrote:
It’s a valid question since it’s used in other forms of motorcycle racing at the highest level. [img]https://p.vitalmx.com/photos/forums/2020/06/04/431049/s1200_C521223E_672E_4207_B1AF_6D55D5C4B31D.jpg[/img]
It’s a valid question since it’s used in other forms of motorcycle racing at the highest level.


McG194 wrote:
Mick Doohan was the first to use it in GP because his leg was so jacked he couldn't pivot his ankle. I think it's a legit...
Mick Doohan was the first to use it in GP because his leg was so jacked he couldn't pivot his ankle. I think it's a legit idea. Rekluse makes one already.
These guys have been making some innovative brake and clutch systems for a while. Pretty popular in the offroad world.
https://www.clake.com.au/
TheNewOriginal 6/4/2020 5:45am
6/4/2020 5:45am
lostboy819 wrote:
This isnt the 250 nervous class at your local knobby way, these guys have mastered turning BOTH left and right, right hand first corner is no...
This isnt the 250 nervous class at your local knobby way, these guys have mastered turning BOTH left and right, right hand first corner is no big deal. Cool
They can also start without looping out, yet they all use the holeshot device.
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Robgvx
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Robgvx 6/4/2020 7:52am
6/4/2020 7:52am
I think it would be a phenomenal advantage to have a thumb brake, for both right hands turns (where you can’t reach the rear brake pedal) and also left hand turns (because your foot is under the pedal).

Of course, though, like holeshot gadgets, it’s no longer an advantage when everyone has them...

I had this idea 25 years ago, and I got around to building one up a few years ago, but there are a host of problems.

Rekluse do sell a rear brake kit but it’s a finger lever, not a thumb lever so that doesn’t really work if you retain the clutch Lever. (It’s designed for spodes who have a Rekluse and take the damn clutch lever off altogether!)

So, I used a KTM front brake master cylinder on the clutch side and fabricated a thumb lever underneath the bars. Using the Rekluse adapter I hooked up the hydraulics to the rear brake master cylinder, so both pedal and thumb lever operated the rear brake. Worked great in principle but here are the issues:

1. The stock rear master cylinder and (small) rear disc aren’t actually very powerful. That’s fine normally because you have tons of power in your foot so getting the bike to stop with a regular back brake pedal is no problem. But the thumb lever is much shorter (and your thumb is weaker than your foot) so getting the back wheel to lock was really difficult.

2. You need the thumb lever to have minimal travel. It needs to move only like half-an-inch to lock the wheel otherwise it’s impossible to use. That means a short lever/close fulcrum. With that short travel and resultant low leverage ratio the rear brake power isn’t enough.

3. That could be resolved with bigger/better rear brake slave cylinder and/or a larger rear disc. But because the rear brake pedal would be working off the same system then rear braking with the pedal would be far too powerful and you’d be locking up the wheel too much with your foot.

Rigging up two independent systems, with a more powerful calliper for the thumb brake (so two callipers on the rear wheel) is overkill.

I don’t know how you could ever get a system that was powerful enough to lock the wheel with your thumb, but sensitive enough to prevent locking it too much with your foot.

4. On the track it was actually really difficult to use. That would get better with practice though. Part of my problem was simply that the thumb lever travel was too long and the brake simply not powerful enough. As I said, the thumb lever needs to lock the wheel easily with minimal force and with a rock-hard, 10-15mm max of travel at the lever. I just couldn’t get that with the hardware I was using.

It also gets really congested on the bars if you have two master cylinders on the left side.

I still think the idea has mileage though, but it would need braking experts to come up with a workable system and hardware.
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JBecker 72
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JBecker 72 6/4/2020 9:00am
6/4/2020 9:00am
lostboy819 wrote:
This isnt the 250 nervous class at your local knobby way, these guys have mastered turning BOTH left and right, right hand first corner is no...
This isnt the 250 nervous class at your local knobby way, these guys have mastered turning BOTH left and right, right hand first corner is no big deal. Cool
JBecker 72 wrote:
It’s a valid question since it’s used in other forms of motorcycle racing at the highest level. [img]https://p.vitalmx.com/photos/forums/2020/06/04/431049/s1200_C521223E_672E_4207_B1AF_6D55D5C4B31D.jpg[/img]
It’s a valid question since it’s used in other forms of motorcycle racing at the highest level.


McG194 wrote:
Mick Doohan was the first to use it in GP because his leg was so jacked he couldn't pivot his ankle. I think it's a legit...
Mick Doohan was the first to use it in GP because his leg was so jacked he couldn't pivot his ankle. I think it's a legit idea. Rekluse makes one already.
Second time I’ve seen him referenced today. It’s also his 55th birthday.
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don'tknowwhy
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don'tknowwhy 6/4/2020 10:06am
6/4/2020 10:06am
Found this on Rocky Mountain's youtube page that might be the perfect setup......IE rather minimalistic without need for separate or piggyback master/slave cylinders and at $199 it's not cost prohibitive.

For $299 they also have a very nice tidy hydraulic left hand operated brake lever as well.

Ox brake cable version hand brake
don'tknowwhy
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don'tknowwhy 6/4/2020 10:12am
6/4/2020 10:12am
Heres the hydraulic version of the Ox brake..... at first glance it looks like a very nicely engineered and tidy set up. $299 for this version.

hydraulic version

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FortyHat
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FortyHat 6/4/2020 11:11am
6/4/2020 11:11am
FortyHat wrote:
You do realize that you have to use the rear brake and the clutch at the same time very often right? Even in RH turns. So...
You do realize that you have to use the rear brake and the clutch at the same time very often right? Even in RH turns. So unless you are using an auto clutch, you got problems. SX and moto aren't like trail riding.
MohMoto14 wrote:
Learn control and stop locking your brakes weekend warrior.
Haha, easy there guy you might sprain a thumb, keyboard warrior. Where do I sign up for your motocross academy?
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lostboy819 6/4/2020 1:56pm
6/4/2020 1:56pm
If they thought there was anything to gain by putting it on a MX bike they would already have done it. Cool
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murph783
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murph783 6/4/2020 2:10pm
6/4/2020 2:10pm
I’ve installed a couple clake systems where the clutch and rear brake are integrated into the same lever. It’s a little funky to get used to but it gets the job done
Bret
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Bret 6/4/2020 2:31pm
6/4/2020 2:31pm
I for one would prefer a lever on the bars for the rear brake. I have really big feet with extra leverage and stalling the engine when I hit the rear brake is a real problem for me.
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peelout
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peelout 6/4/2020 2:32pm
6/4/2020 2:32pm
RandyS wrote:
I think I might have asked this before but I can't remember getting an answer. Why aren't these teams building a small handbrake on the clutch...
I think I might have asked this before but I can't remember getting an answer. Why aren't these teams building a small handbrake on the clutch side for right hand first turns? Is it not legal?
because they don't ride quads
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philG
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philG 6/4/2020 3:28pm
6/4/2020 3:28pm
Rear thumb brakes on road race bikes are used as much for stability as anything else, they are barely used for stopping, you can use them to load up the rear end and also just get the front back down , when your foot isn't in a position to use the pedal, which it isn't at full lean angle . I good friend of mine used to run an Aluminium disc on the rear of his Superbike, because he never ever used the back brake, and the weight saving and gyro saving was noticeable.

For SX, its a solution to a problem that doesn't need fixing.
RandyS
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RandyS 6/4/2020 4:27pm
6/4/2020 4:27pm
PRM31 wrote:
Some MotoGP guys use them.
Are they 250 Novices? I was told only 250 Novices would need that.
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lostboy819 6/4/2020 5:17pm
6/4/2020 5:17pm Edited Date/Time 6/4/2020 5:21pm
PRM31 wrote:
Some MotoGP guys use them.
RandyS wrote:
Are they 250 Novices? I was told only 250 Novices would need that.
Huge diffrent between dirt and pavement, but I can play that game too. Speedway bikes dont even need brakes so the SX guys must suck if they need to brake before a corner, they should just pitch it sideways.Evil you should build and market a system and then sell it and you will be rich because it will revolutionize right hand corners.
blusmbl
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blusmbl 6/4/2020 5:45pm
6/4/2020 5:45pm
I know a couple people that race flat track. Several have had the same thought, being able to use the rear brake in right hand turns while you have your leg out is absolutely an advantage. Several of them set their flat track bikes up with redundant brake levers too - you can't run a front brake in flat track but you can have both a foot and hand operated brake on the bike. So the front brake master cylinder gets repurposed and operates a second caliper on the rear rotor. It is useful for the TT courses where you have right turns as well.
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RandyS
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RandyS 6/4/2020 5:47pm
6/4/2020 5:47pm
PRM31 wrote:
Some MotoGP guys use them.
RandyS wrote:
Are they 250 Novices? I was told only 250 Novices would need that.
lostboy819 wrote:
Huge diffrent between dirt and pavement, but I can play that game too. Speedway bikes dont even need brakes so the SX guys must suck if...
Huge diffrent between dirt and pavement, but I can play that game too. Speedway bikes dont even need brakes so the SX guys must suck if they need to brake before a corner, they should just pitch it sideways.Evil you should build and market a system and then sell it and you will be rich because it will revolutionize right hand corners.
Why so bitter?
ktmwoods
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ktmwoods 6/4/2020 11:28pm
6/4/2020 11:28pm
Robgvx wrote:
I think it would be a phenomenal advantage to have a thumb brake, for both right hands turns (where you can’t reach the rear brake pedal)...
I think it would be a phenomenal advantage to have a thumb brake, for both right hands turns (where you can’t reach the rear brake pedal) and also left hand turns (because your foot is under the pedal).

Of course, though, like holeshot gadgets, it’s no longer an advantage when everyone has them...

I had this idea 25 years ago, and I got around to building one up a few years ago, but there are a host of problems.

Rekluse do sell a rear brake kit but it’s a finger lever, not a thumb lever so that doesn’t really work if you retain the clutch Lever. (It’s designed for spodes who have a Rekluse and take the damn clutch lever off altogether!)

So, I used a KTM front brake master cylinder on the clutch side and fabricated a thumb lever underneath the bars. Using the Rekluse adapter I hooked up the hydraulics to the rear brake master cylinder, so both pedal and thumb lever operated the rear brake. Worked great in principle but here are the issues:

1. The stock rear master cylinder and (small) rear disc aren’t actually very powerful. That’s fine normally because you have tons of power in your foot so getting the bike to stop with a regular back brake pedal is no problem. But the thumb lever is much shorter (and your thumb is weaker than your foot) so getting the back wheel to lock was really difficult.

2. You need the thumb lever to have minimal travel. It needs to move only like half-an-inch to lock the wheel otherwise it’s impossible to use. That means a short lever/close fulcrum. With that short travel and resultant low leverage ratio the rear brake power isn’t enough.

3. That could be resolved with bigger/better rear brake slave cylinder and/or a larger rear disc. But because the rear brake pedal would be working off the same system then rear braking with the pedal would be far too powerful and you’d be locking up the wheel too much with your foot.

Rigging up two independent systems, with a more powerful calliper for the thumb brake (so two callipers on the rear wheel) is overkill.

I don’t know how you could ever get a system that was powerful enough to lock the wheel with your thumb, but sensitive enough to prevent locking it too much with your foot.

4. On the track it was actually really difficult to use. That would get better with practice though. Part of my problem was simply that the thumb lever travel was too long and the brake simply not powerful enough. As I said, the thumb lever needs to lock the wheel easily with minimal force and with a rock-hard, 10-15mm max of travel at the lever. I just couldn’t get that with the hardware I was using.

It also gets really congested on the bars if you have two master cylinders on the left side.

I still think the idea has mileage though, but it would need braking experts to come up with a workable system and hardware.
Now if we get the ZRT throttle tube guy to make one, it’d be just $2499, plus tax.

All kidding aside, used one for supermoto and agree that there is some merit to the concept for SX MX. Racing Glen Helen comes to mind WFO into the talledega right hander....
mark911
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mark911 6/5/2020 4:47am
6/5/2020 4:47am Edited Date/Time 6/5/2020 4:56am
This is a prototype I built awhile back. I tried having the clutch and rear on the same side but it didn't work for me. So I moved the rear to the left along side (but totally separate hydraulically) the front. Work either independently, simultaneously and everything in between. Takes a bit of practice for the muscle memory to develop but it functions fine.

An advantage? It helps me but I suspect its not for everyone. The rear pedal works as well for those panic situations, lol.

I'll be printing some up using Carbon Fiber Peek to test in the near future if anyone's interested.


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