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Heads Up-Homemade Motorcycle Lift Table


Dragracer

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For those of you planning to make this lift, here's an update for you. This morning, as I was lifting the bike up to the first stop, the pipe on the left front broke at the elbow. This caused the table to lean to the right, and the bike fell off! I'm not sure why it broke, but it snapped the pipe off flush with the elbow.

Anyone have a 12' windshield, chrome trim under the windshield, or a light bar? :confused24:

http://i81.photobucket.com/albums/j204/DragracerUSA/DSCN9100.jpg

http://i81.photobucket.com/albums/j204/DragracerUSA/DSCN9101.jpg

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Since I don't know, is black pipe stronger than galvanized?

 

 

Sorry to see ya dropped the bike. Looks like you need to either switch the galvanized piping to black iron or substitute steel.

I would go with steel myself

Good luck & let us know what fix you decided to use

Larry

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Glad it didn't fall on top of ya !

If it were me on the pipe situation , I would investigate on using a larger diameter of pipe as well . There the more sheer factor of wobbling side to side as your working on the scoot on a narrow ramp than it is on the longer span .

I fabricated something on this line many years ago . I found that if you place some re-bar inside the pipe and if it breaks , it would keep a bind on it at the joint (like where yours broke) until I lowered the lift more safely . My lift was similiar , but for raising lawn mowers at a faction of the weight of a RSV .

 

Gene

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Guest KitCarson

Hey Everyone: I am a master plumber, and we still use both galvanized steel and black iron steel in some forms of piping. We use black iron mainly for gas line installations, and galvanized on larger pump and irrigation systems.

There is no difference in the strength or composition of black iron versus galvanized steel, they are both a soft low carbon soft steel, and the only difference with the galvanized is just that, a zinc coating has been hot dipped unto the soft steel to make the piping a little more corrosion resistant for some applications.

I have studied your home-made lift and it looks like a sound design to me........but as with all things engineered the bugs have to be found and worked out.

Soft steel piping assembled as yours is, with the standard method of cutting threads on the piping and fitting the threaded end into the tapped fitting is a weak joint. It was not made to hold any side ways or lateral forces. When the thread is cut into the stock piece of pipe almost 2/3 of the base metal is removed on the starting threads and as the thread travels to the final point, about 1/2 of the base metal is removed. This system was designed to seal in liquid or gas, not to withstand lateral or diagonal stress loads. I am no Charles Atlas, but I can grab a two foot section of 3/4 threaded pipe like that one and break it at the threads with just my hands........so it is a weak joint at the threads as they are cut into the base material.

 

In your case, and in the interest of protecting your bike(sorry about your damage-I hate even one scratch on mine) I would use heavy schedule 80 steel pipe and mitered boss type weld fittings , such as we use for high pressure steam. The pipe is twice as thick as the standard grade shown in your photos and the weld fittings are recessed and quite heavy, this if welded properly will be of adequate strength for this application. You will have to go to a plumbing warehouse to find schedule 80 pipe and recessed steam weld fittings, and may have to special order it. If you live close to a shipyard, you might be able to obtain these materials, quite cheap, in fact a five foot scrap and fittings , someone will give it to you. If you order it , 21 foot section is all you can order(minimum).

 

Hope this helps you make up your mind. You have a good design I think, cut threads are just plain weak, not made for stress loads, made to seal in gas or liquid.

Kit

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That's good info to know there Kit.

Considering the availability of that scheduale 80 pipe and your suggestion of welding it anyhow I think one would just be better off buying standard steel and weld it up. At least that's what I would do.

On standard piping I made a small lift that had a 3 or 4 foot lever that you pilled to raise a bike up on and then let the handle rest on the ground. Mine was made of the black pipe. While it was strong enough for a 550 lb Suzuki it was no where near strong enough for the RSV. Didn't break at my welds but sure bent that levered pipe.

Larry

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Guest KitCarson
Does anyone have the link that shows plans to make this lift?????
Time, effort, money, and whoops.....that did not work..........it will take as much money to run around and buy the materials to make something like this as it will to just go buy one........Pit Bull makes a great lift, has two arm extenders on it for more stability and there is a fellow on this site (Larry) makes a super lift adapter, so you do not have to makeshift some kind of highly dangerous spacers, such as hocky pucks!!! I am going to contact him and purchase one in a month or so myself. The venture is heavy, a little more so on the top than most, does not take much to turn it over.........I almost did once, got my pant leg hung up on the little foot arm that sticks out off the side stand..........and when you turn one over, it always somewhere puts road rash on it......most of us kinda like our bikes, we shine them, clean them, pamper them, adjust them, talk about them, and have a lot of fun on them, do not risk making something and having it dump your bike in the garage or driveway.

 

Kit

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I noticed on your picture all the threads left open on the end of the pipe. Using the info posted so far, all good, you had very little pipe into the elbow, so had a very weak spot there. Not that I recommend anyone building this, as also previously posted, but if you do attempt to build it, make sure the threads are together as far as possible and your luck may hold out somewhat longer.

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All the pipe connections were tightened with 2 pipe wrenches. They were screwed in as far as possible.

 

I noticed on your picture all the threads left open on the end of the pipe. Using the info posted so far, all good, you had very little pipe into the elbow, so had a very weak spot there. Not that I recommend anyone building this, as also previously posted, but if you do attempt to build it, make sure the threads are together as far as possible and your luck may hold out somewhat longer.
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All the pipe connections were tightened with 2 pipe wrenches. They were screwed in as far as possible.

I'm not a Master Plumber, just a master butcher, but two things can be done in error here and I stand to be corrected: One is as discussed, not threaded in far enough and second would be almost the same and that is that the threads were cut too far up the pipe and so giviing the same effect: Not enough material for strength.

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  • 1 month later...

The issue is probably not how much pipe was threaded into the fitting or how it was tightened but in the amount of wall thickness left in the valleys of the threaded pipe. If you were to mic the thickness at the valley you would find it is not very thick and thus not very strong even with a bead of weld laid on it it would not be very strong.

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  • 1 year later...

I built the wood lift table. Instead of the pipe I used 1 and 1/4 inch square tubing from Lowes. Two pieces 4 ft long. I got four 3 foot 5/8 inch round steel rod. I cut the square tubing to 2 foot lenths abd drilled 5/8 inch holes at each end. I drilled 5/8 inch holes in the top and bootom of the table where the piples would have gone. Slipped the roods through and walla. Will post pictures as soon as Painting is done. Tested the lift last night. Works like a charm and no fear of threaded joint failure.

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