GS 1200 Weight?

[Gaz_57]

A mate dropped up the other day with his new KTM 990 ... beautiful tall slim blue thing with orange stripes. Got up on it for a quick 'round the block with no helmet' spin - as you do - Was so very impressed by the apparently nimble / light sporty handling - so much so that i refused to believe that the GS is not considerably heavier.

So we got the bathroom scales out and wheeled the front wheel of the KTM onto it - 110Kgs ... then we wheeled the back wheel onto it - 120Kgs ... 230Kgs all in - fair enough I suppose for a bike advertised as 200Kgs "dry".

Then we wheeled the considerably porkier (looking / feeling) GS out .... Surprise surprise .... 110 Kgs at the front and 125Kgs at the back (including a top box) .... Who would have thought it ??? !!!

 

[Phil Clarke]

Bare in mind that when using that method to weigh a bike you don't just add the front and rear wheel weights up to get the total weight.
Its all about lever arms and moments and centre of mass and stuff. I could probably explain it but it would require too many diagrams....
Phil

 

[dronning]

Bare in mind that when using that method to weigh a bike you don't just add the front and rear wheel weights

To do it right at home you need 2 scales.

KTM 990 185 kg dry
GS12 225 kg with full tank

Dave

 

[JayGee]

Bare in mind that when using that method to weigh a bike you don't just add the front and rear wheel weights up to get the total weight.
Its all about lever arms and moments and centre of mass and stuff. I could probably explain it but it would require too many diagrams....
Phil

Actually you do, if the weight of the bike is W, and the two scale readings are S1 and S2 and the bike is of length L (between tyre contact patches) and the centre of gravity is Y distance from the front then:=
W*(L-Y)=S1*L for the first reading
or W*L-W*Y=S1*L

W*Y=S2*L for the second reading

add these to equations together gives
W*L=S2*L + S1*L
so W=S2+S1
so weight is the sum of the two scale readings .

Of course this assumes the contact patch is a point when it's not so it's not too accurate but roughly right.

Cheers- (wonders to himself- am I bored, have I turned into an anorak, shouldn't I be out riding the GS? )

 

[Fanum]

Bare in mind that when using that method to weigh a bike you don't just add the front and rear wheel weights up to get the total weight.
Its all about lever arms and moments and centre of mass and stuff. I could probably explain it but it would require too many diagrams....
Phil

Like these Phil??

 

[Deleted account 211025001]

Only on a BWM site

Surely the poor guy was just making the point that one bike feels heavier to ride than the other yet actual weight is similar.

They were both weiged the same way and given the wheel bases are probably 'similar' what he did was a fair way of comparing them.

Just a thought though Gaz_57, did you check they both had identical amounts of fuel?

Andres

 

[Eric_Norman]

Like these Phil??

Why when the lorry is going up hill is the front only 4T ?

Thanks
Eric
(no GCSE's only a school certificate!!)

 

[Deleted account 211025001]

Why when the lorry is going up hill is the front only 4T ?

Thanks
Eric
(no GCSE's only a school certificate!!)

Just a moment.........................

Andres

 

[JayGee]

Why when the lorry is going up hill is the front only 4T ?

Thanks
Eric
(no GCSE's only a school certificate!!)

maybe cos the CoG has moved towards the rear, going down hill the opposite will happen.
(degree in clever sums- but still can't add up!)

 

[JayGee]

Only on a BWM site

...
Andres

Too true but then some of us don't get out enough, unlike your name implies , oh! sorry missed the "n"

 

[Piggers]

I think he would have to have a very tall set of scales to make a huge difference. Next time, put the other wheel on a brick or something to bring it to the same height, then no fancy calcs needed

 

[Nice 'n' Fat]

I think this calls for a weighbridge

 

[piebaps]

Did you remember to take off the weight of the pipe and slippers?

 

[GrinningGSer]

Actually you do, if the weight of the bike is W, and the two scale readings are S1 and S2 and the bike is of length L (between tyre contact patches) and the centre of gravity is Y distance from the front then:=
W*(L-Y)=S1*L for the first reading
or W*L-W*Y=S1*L

W*Y=S2*L for the second reading

add these to equations together gives
W*L=S2*L + S1*L
so W=S2+S1
so weight is the sum of the two scale readings .

Of course this assumes the contact patch is a point when it's not so it's not too accurate but roughly right.

Cheers- (wonders to himself- am I bored, have I turned into an anorak, shouldn't I be out riding the GS? )

That is the sort of thing that gives me hours of amusement on this site JayGee

1200GS Handbook says :
DIN unladen weight 225Kg (I do not know what that means )
Dry weght (to EU specification) 211KG

Paniers and top boxes are very heavy mind you

 

[birdseye]

Actually you do, if the weight of the bike is W, and the two scale readings are S1 and S2 and the bike is of length L (between tyre contact patches) and the centre of gravity is Y distance from the front then:=
W*(L-Y)=S1*L for the first reading
or W*L-W*Y=S1*L

W*Y=S2*L for the second reading

add these to equations together gives
W*L=S2*L + S1*L
so W=S2+S1
so weight is the sum of the two scale readings .

Of course this assumes the contact patch is a point when it's not so it's not too accurate but roughly right.

Cheers- (wonders to himself- am I bored, have I turned into an anorak, shouldn't I be out riding the GS? )

It also assumes that both contact points are level - which they arent. The one on the scale is higher than the one on the floor so the bike is at an angle to the flat floor of the garage. The weight measured on the bathroom scale reduces as the cosine of that angle, so that by the time the angle gets to 90 degrees and the bike is stood on its front wheel the weight on the back wheel is zero.

Back in the real world .............................. who cares?

 

[Gaz_57]

"Surely the poor guy was just making the point that one bike feels heavier to ride than the other yet actual weight is similar.

They were both weiged the same way and given the wheel bases are probably 'similar' what he did was a fair way of comparing them."

Too Right Mate - dont know where all that came from - However - just to satisfy the eggheads here - the ground was level, and we have since done it again with two identical scales - no appreciable difference to the figures i gave you already .... Jeeze ....

Maybe spare us the long list of flaws in this latest method? - (and bear in mind that it yielded the same results plus or minus a couple of Kg) ... When i want the figures to six places of decimals - i will call in to NASA. HA Ha

 

[JayGee]

"Surely the poor guy was just making the point that one bike feels heavier to ride than the other yet actual weight is similar.

They were both weiged the same way and given the wheel bases are probably 'similar' what he did was a fair way of comparing them."

Too Right Mate - dont know where all that came from - However - just to satisfy the eggheads here - the ground was level, and we have since done it again with two identical scales - no appreciable difference to the figures i gave you already .... Jeeze ....

Maybe spare us the long list of flaws in this latest method? - (and bear in mind that it yielded the same results plus or minus a couple of Kg) ... When i want the figures to six places of decimals - i will call in to NASA. HA Ha

Just a perverted sense of humour I guess

Your point about the two bikes being almost the same weight whilst the KTM feels much lighter is true. The GS feels like it's going to drop to the side a lot quicker in a turn, or even in a straight line at walking pace and I guess this may make the bike appear heavier to the rider. Whether this is the result of the GS being quicker stearing or just the weight sticking out to the sides I've no idea. IMHO the GS is much better on the road, where I do almost all of my riding so I wouldn't buy the KTM.

 

[Gaz_57]

Actually - I agree ... its all about the weight of the GS when walking around with it - i.e. in and out of the garage / around forecourts etc ... it feels MUCH heavier than the KTM, but on the road, the BMW is definitely superior, off-road there is no contest ... the KTM is actually a feasible prospect .... there you are, you pays your money (n the BMW's casr - all of it!) and you takes your bike. All things considered, i would pick the Beemer if i had the choice again, the only gripe i have is that i am forced to deal with BMW ... other than that, top marks.

 

[Eastriding2002]

I'm with Gaz on this, it's often the walk around the garage test that makes you think a bike is heavier than another.

On riding them the weight often disappears or seems to. I had a Fazer Thou, similar weight to the Beemer, maybe 8kgs heavier, but on slow twisty stuff you would think it weighed a Te more. All the weight was carried hgher up, I then got an Aprilia Caponord which was 16Kgs heavier than the BM but carried its weight lower than the fazer. Only when putting it on the centre stand or turning it around did itsuddenly remind you of its bulk. The GS feels remarkably light to me, weight low down, and very light ore seemingly so on the garage turn test!

 

[Adamm]

work it out

the question of how to work out the answer is not that hard to work out. the intresting thing is that the answer does warrant the question being asked and therefor it needs to be answerd, that answer is 8377.0212 npu/sc/kg

QED!!

Now lets let this be the end of it.

all the best,

Adam