would bathroom scale work for racing
- Thread starter hunter88
- Start date
racing promotor
Moderator
Sure will have done it many times many moons ago, just have them setting solid and level then just do the math.
PrimeTime
Member
When we started we also used bathroom scales, I used a 25lb weight to check each scale to try and make sure they were reading close.
As Ken suggests, make sure all four are level to each other, I also cut a piece of 1/2 plywood and cut a window in
each piece to read the weights, I put the plywood omn top of each scale, this helped the stamped steel top from flexing too much.
It's easy to calculate %'s using a spreadsheet, I made one where you just input your weights
and it output nose, left and cross %.
Dryslick13
New member
The cheap Taylor dial scales work fine. The electronic ones usually will time out and turn off too soon.
ABR #69
Member
They are slightly adjustable to zero them. There is a dial on them to do so, located on the base plate near the dial read out. But, yes I actually have a set sitting in my shop now that I used just to test some things. Make sure they are close to the same though in the store if you can.
TTL = lf+rf+lr+rr
Front % = lf+rf / TTL
Rear % = lr+rr / TTL
Left % = lf+lr / TTL
Cross % = lr+rf / TTL
Pretty straight forward. Just use a pad and pencil in a pinch.
Level is important. The slope in my garage put seven pounds to the nose. Two thin floor tiles under each nose scale leveled it. We marked the floor and each scale and always put the same scale in the same spot. Put a heavy object on each scale, 30-40 pounds, it doesn't matter, then use adjuster on each scale to make each equal.
Be repetitive; always put same scale in same location on floor, put kart on scales facing same direction every time and you will be accurate enough.
Don't think you can drag scales out at the track and be accurate. Get your work done at the shop.
Once you get the hang of scaling you will readily see the changes small adjustments make. It is surprising what 1/4" movements to the left rear wheel makes. Or the how changing castor or camber one degree makes.
DK
Front % = lf+rf / TTL
Rear % = lr+rr / TTL
Left % = lf+lr / TTL
Cross % = lr+rf / TTL
Pretty straight forward. Just use a pad and pencil in a pinch.
Level is important. The slope in my garage put seven pounds to the nose. Two thin floor tiles under each nose scale leveled it. We marked the floor and each scale and always put the same scale in the same spot. Put a heavy object on each scale, 30-40 pounds, it doesn't matter, then use adjuster on each scale to make each equal.
Be repetitive; always put same scale in same location on floor, put kart on scales facing same direction every time and you will be accurate enough.
Don't think you can drag scales out at the track and be accurate. Get your work done at the shop.
Once you get the hang of scaling you will readily see the changes small adjustments make. It is surprising what 1/4" movements to the left rear wheel makes. Or the how changing castor or camber one degree makes.
DK
M.D.racing
New member
Or to go from percentages to wheel weight do this.
Example. Your kart weighs or you want it to weigh 350#. Someone gives you a setup in front,left,and cross percentages. Write them down and figure the weight of each.
46% Front: 350 x.46 = 161# front
57% Left: 350 x.57 = 199.5# left
59% Cross: 350 x.59 = 206.5# cross
Find the difference between cross and left. 206.5 - 199.5 = 7
Add this difference to the front and divide by 2.
161+7 =168. 168÷2 = 84(right front)
(Front)161-84(rf) = 77(left front)
(Cross)206.5-84(rf)= 122.5(left rear)
(Total)350-84(rf)-77(Lf)-122.5(Lr)= 66.5(right rear)
Note: In this example cross weight is higher than left weight. If cross weight was lower than than left weight; you still find the difference between them,add it to the front and divide by two but, the wheel you would be finding is the LF instead of the RF. Then carry on finding the other wheels with simple subtraction. Final note: If cross and left are the same,just divide the front by 2 because both fronts weigh the same in this case.
It's really not that bad and you can do it quickly with paper, pencil,and calculator. Take Care Everybody.
P.S. Good info from Don K above. Always set each scale with a known weight instead of trying to "zero" them....
Example. Your kart weighs or you want it to weigh 350#. Someone gives you a setup in front,left,and cross percentages. Write them down and figure the weight of each.
46% Front: 350 x.46 = 161# front
57% Left: 350 x.57 = 199.5# left
59% Cross: 350 x.59 = 206.5# cross
Find the difference between cross and left. 206.5 - 199.5 = 7
Add this difference to the front and divide by 2.
161+7 =168. 168÷2 = 84(right front)
(Front)161-84(rf) = 77(left front)
(Cross)206.5-84(rf)= 122.5(left rear)
(Total)350-84(rf)-77(Lf)-122.5(Lr)= 66.5(right rear)
Note: In this example cross weight is higher than left weight. If cross weight was lower than than left weight; you still find the difference between them,add it to the front and divide by two but, the wheel you would be finding is the LF instead of the RF. Then carry on finding the other wheels with simple subtraction. Final note: If cross and left are the same,just divide the front by 2 because both fronts weigh the same in this case.
It's really not that bad and you can do it quickly with paper, pencil,and calculator. Take Care Everybody.
P.S. Good info from Don K above. Always set each scale with a known weight instead of trying to "zero" them....
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