1983 Yamaha Venture trunk build for 1500 Nomad

[Work4crown]

Trunk update:

So we went to Americade with the new trunk and everything went fine. None of the hardware became loose and nothing cracked.



The trunk can rock forward and backward a tiny bit because the center bracket latch (that attaches the trunk to the chrome quick release weldment) is a little bit of a loose fit. I'm trying to figure a way to tighten up that fit.

Nikki said the trunk back rest was a good improvement over the stock sissy bar backrest.

The trunk proved very convenient and we were generally surprised that it could hold more than we thought it could. We bought 2 new jackets and we were able to fit both the old jackets, 2 rain suits, some gloves and some other stuff in the trunk. I didn't think it could all fit but it did.

I was surprised today to find that it can hold my largish full face helmet, a thick hooded sweatshirt, some gloves, a can of Honda polish and more.



It's not as big as a Harley trunk for sure but it is much larger than the old mini trunk I used to use.

I did install the battery powered stick on light that has the angle sensing switch. That thing is really nice - very convenient. I have thought about adding some more of these to my saddlebags.

Some of the steel plates & brackets inside the trunk that I had painted black got scratched on the trip. I think we might powder coat those in the fall for a more robust finish.

Also, the lift struts I used are not strong enough. They are 30 psi each. So I ordered some new ones that are 50 psi each and we'll see how that goes. The 30 psi struts are not strong enough to open the lid by themselves but they are strong enough to keep it open. I'm hoping to add some pressure so that when I unlock the trunk it opens it self. I'll report back on that once the new struts come in.

[JD Hog]

Very nice job on this project

I am spoiled having a trunk and could not go without it. Especially when my wife or daughter is with me.

[Loafer]

I hope you two enjoyed the cabin, and that you didn't see too much rain.
The bike is looking fantastic!

[Work4crown]

After the trip to Americade I decided to take the trunk off and apart to see how the lower half plastic was holding up. I had repaired some holes and cracks using a solder gun, ABS patches and ABS cement.

I noticed the cracks were starting to show up in the same old places again.







So I decided to remove the metal plate I had added and add a thick layer of 'Bondo Hair'.







It would not need to be pretty because I would add the metal plate over the top of it.

I also added some Bondo Hair to the back wall of the trunk around the area where the two locks are. There was a hairline crack showing up a tiny bit there as well.

The trunk feels much more solid now and gained a little weight. I'm hoping all of these mods will give this thing the strength it needs to support my passengers and gear.

Also, the trunk was able to pivot a little on the quick release mount because there was an .080" gap between the locking latch bracket and the chrome quick release weldment. I drilled a hole in the lock latch bracket and added a socket head cap screw with a lock washer to take up the gap.





Now the trunk can't pivot and feels much more solidly mounted.



I was using two 30 psi lift struts but they weren't strong enough to lift the trunk. So I tried two 50 psi struts. That was way too much pressure. It turns out one 50 psi strut can easily lift the lid but that is too much pressure for one side of the trunk. The 30 psi struts I was using were used and must be worn out because both of them together don't have as much pressure as one of the 50 psi struts. Even one of the 50 psi struts was enough to push the lid upwards when the trunk was closed and exert too much pressure on the trunk. I think if I had to do it again two 20 psi struts would be worth trying.

[Work4crown]

I finally got around to replacing the gas struts. I calculated the required force would be 8.66 lbf for each strut. So I ordered two 10 inch 10 lbf gas struts for $15 from Amazon. It is enough pressure to lift the lid when the trunk lock is turned.

I based my calculation on the math in this video


Here is what the video teaches:

Use a bathroom scale on the inside of the trunk (without struts) to measure the force (lbs) the lid exerts on the scale. (I measured 4.25 lbs)

Measure from the hinge pivot to the back of the trunk where it touches down. (I measured 18.375 inch)

Calculate Torque: Torque = Force x distance (example Torque = 4.25 lb x 18.375 inch = 78 lb in)

Measure the distance from the hinge to strut mount (example: 4.5 inches)

Solve for force: Force = (Torque/hinge to strut mount distance)/2 struts = (78 lb in/4.5 inch)/2 = 8.66 lbf

The smallest 10 inch strut I could find was 10 lb force. Since my calculation said I only needed 8.66 lbf (each side) to cause the trunk lid to be weightless when closed I expected the 10lbf struts to exert a little upwards force when the lock is unlocked and therefore open itself without my help.

In practice the trunk does open itself; at least for now. As time goes by the force of gas struts diminishes and eventually I will have to help open the trunk.

Update 6/26/2923: The 10 lb struts seem to have settled in place and no longer push the trunk lid up as soon as the key is turned. Now the trunk stays closed and you have to lift it a little to get it to open by itself the rest of the way.

[Mechaniac]

Nice work.