[DDC]

Hi guys,
Another newbie question:

My Burgman 400 has better braking from a small, single disk on the rear than from the twin, large disks on the front. I find this incredible but am convinced it is true.

All the motorcycles I have had were much better at braking on the front wheel than on the back and would nose dive instantly if front brake applied hard.

So what is going on here? Am I imagining things or is there a reason for this phenomenon?

I only notice this at low speed because I don't usually use the rear brake on its own other than low speed maneuvering . Usually I brake both together or with the front a split-second before the rear.

The brakes seem to do the job so I'm not worrying about this - just interested.

 

[Bluestrom13]

I ride both scooter and bike.

I will (almost) agree with you. The rear brake is proportionately more effective than the front, compared to my bikes. I wouldn't say better.
I certainly use it more than when on the bike. But then the scoot doesn't have manual gears to slow with.
The Burgman definitely stops as well as my V-Strom did, maybe better. It weighs the same. same number of discs, but smaller.
Could it be as a result of combination of longer wheelbase, lower c of g, less suspension travel on front forks (so less dive), and more weight toward the rear?
Not that I have ever noticed a problem with that latter one, handling-wise.

 

[G-Dub]

In my experience the front should still stop way better than the rear. Difference in rear brake feel could partly be due to hand vs foot control. Since the bike is brand new (I assume?) maybe the pads are just not broken in well yet? Maybe some air in the lines? First I would clean the rotors with some brake cleaner on a rag. Might also try strapping down the front brake lever overnight which may allow any bubbles to percolate out, and\or bleed them.

As an aside, I was never happy with the front brakes on my Suzuki GSXS from new, nowhere near as good as stock V-strom brakes. Had to bleed them several times to get the sponginess out, disc cleaning helped, but ultimately ended up replacing the pads with Vesrah to get the feel I wanted.

 

[zrx212]

I've found that most conventional scooters with engine/cvt/swingarm combination have more or similar stopping power on rear brake, compared to front, the answer is actually simple, weight or more specifically weight bias, etc, to KISS and not get into the math of it simply put there's more weight on the rear tire.... etc.

 

[Charbroil]

The brakes seem to do the job so I'm not worrying about this - just interested.

The brakes aren’t power assisted like a car, so they only have the energy that you supply. Other than the master vs total slave piston area ratio, it depends on the force at the levers you provide. Are you sure you’re squeezing both with the same force? Are you positive your hand grip strength is the same in both hands? Let someone else try the bike. If they also come to the same conclusion, then I’d suspect glazed front pads, or rotors.

 

[mikeyMarine]

yeh, the fronts on my 15 650 are good enough I have no problem doin a stoppie but I caint do a stoppie with the rear. (notice: nowhere did I say I actually DID a stoppie ..... maybe that one time in a chevy vega)

 

[G-Dub]

If it was just weight ratio\more rear weight, seems that would only be a factor if the rear totally lost traction on a standard motorcycle? Or are you suggesting it's designed that way due to that tendency?

 

[Charbroil]

Vehicle weight shifts to the front during hard braking. That’s why front brakes are larger

 

[mikeyMarine]

If it was just weight ratio\more rear weight, seems that would only be a factor if the rear totally lost traction on a standard motorcycle? Or are you suggesting it's designed that way due to that tendency?

sometimes the rear on a standard bijke does lose traction during braking, if you do a crappy downshift while braking the tire skips and ruins your skivvies

 

[Charbroil]

yeh, the fronts on my 15 650 are good enough I have no problem doin a stoppie but I caint do a stoppie with the rear. (notice: nowhere did I say I actually DID a stoppie ..... maybe that one time in a chevy vega)

a stoppie on a burger?😳

 

[G-Dub]

The only time I ever slid the rear on a motorcycle or scooter was on the Helix (which has a pedal for the rear). Light changed to red and I may have been exceeding the speed limit a tad. Rear tire slid all the way to a stop, squealing the whole time. I didn't even look around at the other drivers, just acted like I did it on purpose.

 

[Abner Bjorn]

70% of your stopping power should come from the front. It's easier to stop a vehicle by slowing the forward momentum then dragging it from the rear. That's why older cars had discs on the front and drums in the back. That's why your Burgman has two discs on the front and one on the rear.

 

[Charbroil]

It’s all about weight transfer. When MikeymMarine’s doing a stoppie on his Burgman, 100% of his rear tire’s weight has transferred to the front wheel , so the rear tire has 0 lbs on it and the front wheel now has the 600 lb plus the rider’s weight on it, giving 100% of the bike’s stopping power.

 

[Bluelobo]

I have noticed the same thing. I come from riding motorcycles and the rear seems much more effective and even more effective than the fronton the burgman. On the MC I often didn't even use the rear or only a light touch for typical stops. Definitely feels a lot different.

 

[Bluestrom13]

Not to get involved in the math(s), but this diagram*** illustrates what is involved.
At the bottom they make reference to 'h' being roughly equal to 'a' and 'b'.(As in 'motorcycle).
I would say that our machines have ''h' which is smaller than 'a' and possibly 'b', so weight transfer is less.
(***The full PDF document is available here, if you're interested)

https://www.researchgate.net/publication/228430661_On_the_Braking_Behavior_of_Motorcycles/link/561bdacc08aea80367243152/download

 

[zrx212]

Can't compare a "Conventional" scooter like the B400 to any motorcycle or to the B650 for that matter, completely different configurations, on a conventional scooter the heaviest item (engine/transmission/swingarm) is low, is unsprung weight and is sitting mostly on rear wheel, not centrally located, etc. Very different dynamics, also KIM that even if you're pulling the lever hard, the ABS is really "running the show" on so equipped scooters/bikes.

 

[Charbroil]

For those that may not know the term ‘ stoppie’ it is the opposite of wheelie. = 100% weight transfer =100% brake power from front wheel.

 

[G-Dub]

I didn't know anybody was taking my picture!

 

[zrx212]

For those that may not know the term ‘ stoppie’ it is the opposite of wheelie. = 100% weight transfer =100% brake power from front wheel.

Yes, also most sportbikes have a 52-56% front weight bias to help with front wheel contact/stability and helps to do stoppies, I did several unscheduled stoppies on my 99ZRX1100 back in my lighter years

 

[Chuck007]

Hi guys,
Another newbie question:

My Burgman 400 has better braking from a small, single disk on the rear than from the twin, large disks on the front. I find this incredible but am convinced it is true.

All the motorcycles I have had were much better at braking on the front wheel than on the back and would nose dive instantly if front brake applied hard.

So what is going on here? Am I imagining things or is there a reason for this phenomenon?

I only notice this at low speed because I don't usually use the rear brake on its own other than low speed maneuvering . Usually I brake both together or with the front a split-second before the rear.

The brakes seem to do the job so I'm not worrying about this - just interested.

I Use both to sit burgmans 400 and 650 down depending on turn, road or gravel. Yes gravel. ✅

The important thing from typical street bike is where the weight is as already described by other poster here, best piece of advice when I went to max scotters is don't panic stop on front brakes alone or over biased.

It will always likely low side you. I use rear more BUT with control of front. Never one or the other only. Within riding style preferences i guess.

Notice how going into a turn the scooter sits/squats, when back brake applied and inturn pitched forward on forks when front brake applied? Play with it, until you gain smoothness and controlled operation reducing pitching.

Remember when wheels have reduced weight they have reduced grip. The opposite is also true to a point, until they slip or loose grip.

Abs helps for sure if u have it but nothing feels better than apexing a corner at speed balanced and confident, leaving a squid 🐙 on their crotch rocket 🚀 ,wondering if they are on the right machine lol

Ps anything on two or three wheels and a motor is nirvana for me. Not judging or flexing 💪

Cheers

Hope that helps.