The rear brake. Who uses it?

[Ocean1]

With infinite time or money I'd love to put a thumb brake on the dirtbike as a rudimentary traction control in the slippery stuff.

Seen those clakes? Haven't met anyone that's tried one...

I have to remember to keep away from the lever after being out on the dirt as I tend to overuse it for a while till I retrain myself.

I get that. After a day out on the dirt bike I have to consciously lay off it on the road.

[Shaun Harris]

I'm learning to use it...off road.

Think Stroudy uses it to compress the rear suspension you'll find. When the rear is jacked up, the chain tightening stops the suspension compressing when ya roll the gas on. So you lose compliance and traction.

But if you load the brake and get the swingarm angle close to flat you can overcome that, and enjoy the advantages of both worlds.

You are on drugs buddy

[Drew]

You are on drugs buddy

You've ridden bikes with the swingarm pivot too far above the axle height, no? They light up the tyre something fierce on corner exit. Took a long time to figure out that's what was causing me to lose speed and drive on my superbike.

'Anti squat' is what some people call it. It means that the front doesn't rake out as much when you load up the rear, and can hold a tighter line...untill of course the power of your bike overcomes the available traction of the tyre. Then the line tightens up MIGHTY quick.

The rear brake isn't used to reduce power, it's to sort the geometry of the swingarm in this application.

[Shaun Harris]

You've ridden bikes with the swingarm pivot too far above the axle height, no? They light up the tyre something fierce on corner exit. Took a long time to figure out that's what was causing me to lose speed and drive on my superbike.

'Anti squat' is what some people call it. It means that the front doesn't rake out as much when you load up the rear, and can hold a tighter line...untill of course the power of your bike overcomes the available traction of the tyre. Then the line tightens up MIGHTY quick.

The rear brake isn't used to reduce power, it's to sort the geometry of the swingarm in this application.

You have simply been reading to much stuff and baffled yourself with bullsit and are now just pretending that you actually know what you are talking about dude

Open throttle suspension squats which tightens chain

What year model superbike could you not ride like all others could with the swingarm faults that you mention

And yea have ridden heaps of bikes with slight issues including the tryphonas and the Britten, so loads of test riding done

[quickbuck]

Open throttle suspension squats which tightens chain

Ummmm,
Not how I was taught..... (excuse the pun)

Open throttle this happens:
The primary gear pulls on the chain. The reaction is that the rear sprocket gets pulled closer to the engine (As the tyre has the weight of the bike and rider to PUSH along).
This usually means the rear of the bike actually RISES..... unless something else is done to the suspension or geometry to prevent this from happening.....

[Shaun Harris]

Ummmm,
Not how I was taught..... (excuse the pun)

Open throttle this happens:
The primary gear pulls on the chain. The reaction is that the rear sprocket gets pulled closer to the engine (As the tyre has the weight of the bike and rider to PUSH along).
This usually means the rear of the bike actually RISES..... unless something else is done to the suspension or geometry to prevent this from happening.....

OK, so when you open the throttle, does the shock use any more stroke at all?

[Drew]

You have simply been reading to much stuff and baffled yourself with bullsit and are now just pretending that you actually know what you are talking about dude

Open throttle suspension squats which tightens chain

What year model superbike could you not ride like all others could with the swingarm faults that you mention

And yea have ridden heaps of bikes with slight issues including the tryphonas and the Britten, so loads of test riding done

I would certainly not question your experience, so it surprises me that you don't understand what I'm trying to say.

Ummmm,
Not how I was taught..... (excuse the pun)

Open throttle this happens:
The primary gear pulls on the chain. The reaction is that the rear sprocket gets pulled closer to the engine (As the tyre has the weight of the bike and rider to PUSH along).
This usually means the rear of the bike actually RISES..... unless something else is done to the suspension or geometry to prevent this from happening.....

This is what I'm talking about...more indepth to follow...

OK, so when you open the throttle, does the shock use any more stroke at all?

Yes it does, unless the swingarm angle is so steep that the chain tension is 'binding' it up.

The sprocket is in front of the swingarm pivot. So, the chain is at it's absolute longest when the line between the sprocket, swingarm pivot, and axle are all dead straight. If you start loading the throttle/chain before that straight line, the weight transfer can be insufficient to overcome the chain trying to shorten that distance. This stops the rear suspension compressing. So the only 'give' left when the tyre hits a bump or whatever, is traction.

The upside to having the swingarm at a severe angle is still a bit of a mystery to me. It certainly makes for more stability on fast direction changes in my experience, but other than that I am only guessing. More weight on the front wheel at turn in is an obvious one I'm willing to bet on though.

So, in response to "pretending to know what I'm talking about". Suck my dick old boy. I have personally experienced the effects, and had to research the explanation to fully understand it.

[Shaun Harris]

I would certainly not question your experience, so it surprises me that you don't understand what I'm trying to say.

This is what I'm talking about...more indepth to follow...

Yes it does, unless the swingarm angle is so steep that the chain tension is 'binding' it up.

The sprocket is in front of the swingarm pivot. So, the chain is at it's absolute longest when the line between the sprocket, swingarm pivot, and axle are all dead straight. If you start loading the throttle/chain before that straight line, the weight transfer can be insufficient to overcome the chain trying to shorten that distance. This stops the rear suspension compressing. So the only 'give' left when the tyre hits a bump or whatever, is traction.

The upside to having the swingarm at a severe angle is still a bit of a mystery to me. It certainly makes for more stability on fast direction changes in my experience, but other than that I am only guessing. More weight on the front wheel at turn in is an obvious one I'm willing to bet on though.

So, in response to "pretending to know what I'm talking about". Suck my dick old boy. I have personally experienced the effects, and had to research the explanation to fully understand it.

Love ya to honey


Every single motorcycle on the road or race track in New Zealand is subject to exactually what I said, open throttle shock stroke gets used, chain tightens!

Another point class room 101, The chain should be pre set everytime to allow all the FULL STROKE of the shock to be used without the chain becoming to tight to not allow shock stroke to be used.

What you are saying is tech correct of course and we have probbally read the same articles on it Drew, but as per most things on the internet, it is being used out of context for the question from the OP




PS, my spelling still sux so beat me

[Drew]

I was just explaining my observation of Stroudy using his rear brake. I'm not an advocate for jacking up the rear of the bike. I headbutted my own front tyre once without falling off, from a very near highside. TonyOK was behind me laughing his arse off at the sight of me doing a headstand over the front of the bike exiting Higgins at Manfeild.

It is all academic anyway. An NSR is not likely to have the poke to overcome the weight transfer, 300 kitted or not. I'm referring to my own Haldane built real deal 190 horse superbike, and Mr Stroud's own similar machines.

The rear brake in my opinion is redundant under race braking conditions for the purpose of slowing down, but many people far more skilled than I use it for other reasons on the track.

[scrivy]

FUCK ME!!

I think I need to throw you two in the 'Dungeon' with a keg of beer, a 2 litre container of lube, a double ender and some frozen chickens.......

Geezus H Christ......

[Dreama]

I am making one. MTB brake lever with cable pulling master cylinder plunger up. Will try direct pull first. If that don't work then will use a lever at the master with different leverage points. Cheap and choice. If it is reliable.

Back to thumb brakes .. this is mine. I was never skilled enough to coordinate myself to use it properly .. it's surprising how difficult it is to find the time to think of all that sort of stuff when the brain is obsessed with dealing with sensory overload.

[F5 Dave]

Seen those clakes? Haven't met anyone that's tried one...



I get that. After a day out on the dirt bike I have to consciously lay off it on the road.

Yeah back to the less handbags at 10 paces conversation ; yeah I have read about them. Not quite and too speedy for me. Justin had a bodge system on his KTM due to a rekluse that looked worth pursuing, but then time is too short for every project.

[Shaun Harris]

Back to thumb brakes .. this is mine. I was never skilled enough to coordinate myself to use it properly .. it's surprising how difficult it is to find the time to think of all that sort of stuff when the brain is obsessed with dealing with sensory overload.

But did you have it up and running though?

[Shaun Harris]

FUCK ME!!

I think I need to throw you two in the 'Dungeon' with a keg of beer, a 2 litre container of lube, a double ender and some frozen chickens.......

Geezus H Christ......

I suppose it does ftr in with all the shit talk of sidecar racers

[Drew]

I suppose it does ftr in with all the shit talk of sidecar racers

Na, I'm usually wrong when talking about sidecars.