Wilsons Sandbox

Steve Anderson wrote:

> Does anyone have any suggestions on how to weigh a loaded KLR? I am > interested in trying to figure out how much weight is up front, and how much > is on the back. My bathroom scale only goes to 300lbs, which should be fine > for the front, but will obviously probably not be up for the rear.

Look in the phone book under "weighbridges"? If you can weigh the front yourself, and can get the total weight at a weighbridge, then you can calculate the rear weight. Mister_T

> List, > > Does anyone have any suggestions on how to weigh a loaded KLR? >

Is there a grain elevator within a reasonable distance ? Their truck scales are pretty sensitive. They probably would get a kick out of it and wouldn't charge you. Bogdan

I used this method successfully on my KLX. Just make sure to put the tire that is not on the scale on some blocks so that the tires are level. Ed

--- In DSN_klr650@y..., TLrydr@a... wrote: > Steve, > Put the front tire on the scale then put the rear tire on the scale, Add > front number to rear number and you have the total Wt. I tried this on a few > of my bikes and it works. > Broke the scale about a month ago trying this on my Gold Wing LOL. > > Mike

--- In DSN_klr650@y..., Bogdan Swider wrote:

> > Does anyone have any suggestions on how to weigh a loaded KLR? > > > Is there a grain elevator within a reasonable distance ? Their

truck scales

> are pretty sensitive. They probably would get a kick out of it and

wouldn't

> charge you. Bogdan

Yep, or go to a landscape supply, they have quite accurate scales for selling stone by the pound. When I go there in my car, I weigh the car empty, then go load the trunk up with stone material, then the car with load gets weighed. I think these scales are pretty accurate. Or you could stop worrying about how much it weighs, since you already know it weighs too much.

> At 75lbs on the rear rack, it is overloaded, > but I've carried that much on it for many miles in the past over very > rough > conditions so I'm not too worried about that. Even if the rear is too > heavy, will that stop me? Will I worry? Probably not... ;-} > > > Driving around with it like it is now, the worst problem is that because > my > "long" (~55") bag is mounted ends pointing to the sides, the wind kind of > screws with me up as I get up around 75mph. Handling overall is a little > goofy, but seems like I can get used to it. >

Boy my experience and beliefs are way different. I carry all heavy stuff, tools, water, booze and books in my tank panniers and jumbo Chase Harper Euro-Sport tank bag. Light bulky items fill my 36ltr Givis. If I cheat just a bit, say put a water bottle or two in the back, the bike feels less stable at speed or off road. I consider that condition dangerous. Not something "goofy" that one can get used to. Bogdan

I keep reading this... "Make sure the other tire is on a block" What if you aren't level and one tire is 1.5" inches higher than the other? Hey guys and gals... it doesn't matter enough to worry about it. Measure both ways and tell me the difference. Better yet calculate the force vectors for both conditions and tell me the difference. I did and I get less than a 1% difference. 1% is better than the accuracy of your bathroom scale. But I didn't use a bathroom scale I used a load cell, that is calibrated to .25% accuracy. That doesn't matter though, so long as you are center loading the scale. The gas doesn't flow back enough at that small of an angle to change your center of gravity significantly, the oil doesn't flow back enough either. Now what about if you wanted a wheel weight with rider. You'd have to have someone hold your bike upright for you as your feet were on the pegs. If your feet aren't on the pegs then you'd have a combined center of gravity further back than if your feet were on the pegs. That would change your wheel weight by about 1-2%. WHO THE HELL CARES ABOUT 2%? It doesn't matter since they are both so close. They are close enough that other measurement errors would cloud the real number. Now you want a total weight with rider... Get two scales and make sure they read the same number for the same wheel (or note any offset). Then place one scale under your front tire and one under your rear tire. Add the numbers, add or subtract the offset and that's your weight. If you only have one scale then go buy another... Or use the one scale under each wheel one at a time and add the numbers. Don't worry about a block or your tires being level cause it doesn't matter and if you're anal enough to need a number right down to the pound then you shouldn't be using a bathroom scale to do this. You really don't want to read the next part. Now a word or two or three about percentage accuracy. An instrument is calibrated or verified to have an accuracy within some percentage. I'll talk about force as it doesn't matter what value you are measuring and most instruments are calibrated in the same manner. You have a 1kip load cell (1000 pounds). You want to know it's accuracy. Dead weights are the most accurate way to verify a load cell, so you take a calibrated 100# weight and place it on the load cell, you record the number. Then 200 then 300 etc. Then you find the recorded value that is furthest away from the reading it should be. Lets say it reads 906 instead of 900 pounds and the 6 pounds is the largest Delta F for each of the readings. You take that 6 pounds and divide it by 1000 and you get .006 or 0.6% of Full Scale. That means that any measurement in the range will be equal to or better than 0.6% of 1000 pounds or within 6 pounds. BUT 6 pounds difference at 100 pounds range is a full 6% off, wow what a discrepancy... Well that's measurement for you. In reality your Delta F with the 100 pound weight may have been only 2 pounds. Still that's a full 2% difference at that range. So what does that all mean. You can't weigh a marble on a bathroom scale, and you can't weight your bike on a truck scale. Some instruments are calibrated and verified for accuracy within a 60% range. That is you don't trust your numbers at less than 20% of full scale and you don't trust your numbers at greater than 80% of full scale. Of course that's not practical for many measurements, but the idea is that if you have a prediction of where your value will be then choose an instrument that has a full scale of roughly twice that. That way you are measuring right around the 50% of full scale area, where the instrument should be the most accurate. Would I weigh my bike with a 1kip load cell, yeah, cause I know that it'll be within some small range. An average instrument is calibrated to 1% of full scale. High precision instruments tend to be around 0.25% of full scale. But don't be fooled by "of full scale" when you are measuring something. Of course there are other ways of stating the accuracy of an instrument. Some people combine linearity, repeatability ad hysteresis in the accuracy percentage they claim. Some people claim it at 50% Full Scale and other people take the Delta F for each reading and calculate the accuracy at that reading (2% in the above 100# case) then take the worst or highest percentage of each of the readings and make that accuracy percentage for the instrument. But that method doesn't sell instruments as it is usually much much higher than say 1% FSO. See you didn't want to read that... I told you so. LaterZ Dash At 04:18 PM 3/27/2001 +0000, Ed Boyd wrote:

>I used this method successfully on my KLX. Just make sure to put the >tire that is not on the scale on some blocks so that the tires are >level. > >Ed

--- In DSN_klr650@y..., Bogdan Swider wrote:

> > > > > Boy my experience and beliefs are way different. I carry all heavy

stuff,

> tools, water, booze and books in my tank panniers and jumbo Chase

Harper

> Euro-Sport tank bag. Light bulky items fill my 36ltr Givis. If I

cheat just

> a bit, say put a water bottle or two in the back, the bike feels

less stable

> at speed or off road. I consider that condition dangerous. Not

something

> "goofy" that one can get used to. Bogdan

It's really not that bad, it doesn't feel any worse than having a passenger. Heck I've had passengers that were worse because they moved around so much! Mostly goofy because of the wind on the long bag. I would love to move the weight up front but the stuff is just too long. Where else on the KLR do I put a 55" X 12" X 14" bag? I am thinking of getting a large tank bag to put the tools, etc. that is in the small back pack on the back, but I'm going to wait until I get my tank panniers to make certain everything works together ok. How big is your tank bag? Are your tank panniers any larger than the Aerostich? Steve A.