A thread about Weight

[Erik D_lux]

I would like to start a thread about weight and the Losi. Feel free to add anything you like. Wheel weight, ESC weight, balance from front to rear or just anything that you think has helped you along the way.

I will start... hopefully its not too long winded. I have quite a bit to share.

I have become somewhat obsessed with the weight on the Losi. It all started when I got some Vanquish DH wheels (the ones with the bullets). The wheels are made so its really easy to pull weight and figure out what you want to run. Before I got the wheels I settled on 16oz, a full pound. I didnt really feel like pulling my whole beadlock apart to test and see what I liked better. You could have convinced me to run 17oz or even 18oz at that point.

I started testing and found that by taking some of the weight out it didnt really hurt my ability to climb but it helped it a TON. There is a fine line where you want the front to have more weight so you dont tip over backwards, but the less weight you have, the better you are (less stress on parts, more wheelspeed etc,.

Anyway, my point is, I have found that moving weight or getting rid of weight has helped my car a TON. In the next few posts I will show what I have done and what I think has helped. Take it for what its worth...

[Erik D_lux]

I have found that I like my rear end as light as possible. One thing I have found to help is the stock LCC wheel. You just cant beat it for weight and its very durable.

1.6oz for a complete wheel.

I cannot find anything lighter that is durable. I do have some night crawler rings on the way. I guess they are plastic. This should bring the weight down some more. I will post up when I get them.

A LCC wheel with lots of foam, worn out HB rover tire is 5.1oz

[Erik D_lux]

Links can reduce weight, help clearance and help you slide. I have some home made 3/16 Titainium links.

Stock AL links are 1.9oz


Ti links came out to be 1.6oz.

[Erik D_lux]

I butchered my chassis pretty good.

Stock PER SIDE 1oz



Butchered chassis .7oz PER SIDE. More importantly it is one of the highest points. Note that I also cut as much as possible out of my shock arms. Carbon fiber shock arms are for rich folk. Its another good option though. I would like to see weight savings of those over stock.

[Erik D_lux]

I am not sure how much weight is saved on these but, they are functional and do shave a bit of weight.

I leave the pinion cover off and I cut the front of the trans housing. This way I can see what is happening at all times. Next time I have it apart I will get some weights



If you dont run your dig servo on the top of the trans you can cut off the back end of it. I dont think you lose too much weight but, if you cut it right you will leave a very small hole. This is great for adding lube. When I lube my worms I lube my trans. It helps a TON.

[Erik D_lux]

You can ditch at least 2 of the 4 cross posts in the top of your chassis. I also ditched the other 2 and made some Delrin cross posts. Again, one of the highest spots of the chassis.

Stock AL posts .3oz



Delrin posts .1oz

[Erik D_lux]

You can run a mini servo for your dig instead of a larger one. Per Hitecs specs...

HS81 .58oz

HS225 1.10oz

HS645 if youre crazy 1.94oz

[Erik D_lux]

Lastly, the latest mod that I did today helped so, so much.

I have been hanging with an Axial ax-10 guy. He had the servo/battery mount on his front axle. This allowed him to place everything else up front and leaving no weight in the back. I was jealous of this but I could not find a way to run my steering like his. The only thing I could think of was to place my lipo on top of my servo. I never went through with this for a long time because I thought you would have to be a complete idiot to place your lipo that high. Well..., I was that idiot today.

I moved my ESC and BEC on top of my links along with my radio receiver. I then put my Lipo on top of my servo. The results are nothing less than awesome! I was worried about raising my center of gravity but it seems like it helped it. By doing the test where you place your car on its sidewalls it is more stable. Climbs are MUCH easier with no weight in the back too. The only downside is that I now have to change my foam and shock setup in the back because it changed it so much. I also dropped another ounce from my front wheels because the weight moved up. Thats another 2oz total off the weight of my car.

Everything moved up front:



Total weight with no body, lipos or wheels/tires 2lb 13.1 oz. Not too bad for just doing mostly free stuff. I could still lose some weight off my front axle but I am not sure I am that concerned with the front axle weight as of yet.



Front axle only. 1lb 10.5 oz



Rear axle only. 1lb 2.3oz





No body, no lipos. 5lb .01 oz



Complete, ready to run. 5lb 7.1oz

[Erik D_lux]

Oh yeah. Last but not least... Keep your wires down low in the chassis and keep them as short as possible. Even your servo wires. Cut them and solder them to a short length.

Thanks for putting up with my rambling. Now lets see what you got!

[wrightcs77]

Aluminum screws and nuts anywhere on the chassis. The aluminum screws and nuts are about 1/3rd the weight of the stock steel pieces. The screws that mount the shocks to the chassis, I would do titanium, for strength reasons.

You can do aluminum screws in the rear housing, too, if you are trying to reduce weight in the back.

Aluminum or titanium screws in the rear beadlocks might be an option, too.

I did not like the stock wheels, because I broke out the center of multiple wheels on tumbles. I liked the VP SLW, which weigh in at 2.1 oz for the rims and rings, about .5 oz more than a stock wheel. The bonus is you can get the rig narrower, stock width, or wider as you desire. Mayhem has a rim that is as light and has variable width, too.

Light weight dig shafts and forks are good. Also, Losi is going to release (or has released) light weight aluminum outputs that save probably 50% over the stock steel outputs.

[rob_b]

Your heart's in the right place, every gram counts

My .02 on link materials...

I'll make it overly simplified and just compare 3" of different materials.

3/16"
Steel - 10.4g
Ti - 5.9g
Alum - 3.6g
Delrin - 1.8g

1/4"
Steel - 19.1g
Ti - 10.9g
Alum - 6.4g
Delrin - 3.6g

5/16"
Steel - 29.5g
Ti - 16.8g
Alum - 10.4g
Delrin -5.4g

Long story short, for light and strong upper links I believe 3/16" alum to be the sweet spot. For lowers 3/16" Steel or Stainless links are nice. Also if you switch to revo/jato ends you can thread the 3/16 with a 10-24 or 10-32 directly and ditch the steel set screws. Also remember that links and anything mounted on them are roughly 50% sprung and 50% unsprung weight. If you really want to get weight off the chassis it needs to be mounted to the axle directly. I made these uppers and dropped 12g total over the stockers.

[djjiz]

My transmission feels empty after the lightweight goodies from wreightcs77. I suggest this to anyone that's counting grams.

Here's a link to the alum outputs http://www.losipartshouse.com/servle...-Center/Detail

[scatterbrains]

Ok scaled my LCC, RTR weight im sitting at 5.3lbs. all aluminum trans minus outputs, alum c's knuckles. Runnin ti hinge pins, CF shock arms. SLW wheels in back, and mayhem 7's in front shod with sedonas.

Weight bias is as follows front axle is 3lbs rear axle is 2.25lbs.

Ill prob end up stickin another 6oz on the front. Ill see how it runs on sunday

[losikid]

I've considered doing a weight overhaul, just never really any inspiration for it. Although the way you talk i may put my lipo on my servo so i can mount my elecs on the skid instead of on a elec plate i made on top of the chassis making it more top heavy,

[djjiz]

What body are guys running with the battery on the servo?

My stocker already bottoms out and judging by the dents and chunks out of my servo case I'd hate to expose my cells to that abuse

[Erik D_lux]

Originally Posted by wrightcs77

Aluminum screws and nuts anywhere on the chassis.

I was putting off the different screws because I only thought of the TI upgrade. Thats just too much money for me for a little gain. I didnt think about aluminum.

Like you started out, maybe it would be cool to list where AL works and where TI works. I am going to take a look at it.

Originally Posted by rob_b

My .02 on link materials...

I'll make it overly simplified and just compare 3" of different materials.

3/16"
Steel - 10.4g
Ti - 5.9g
Alum - 3.6g
Delrin - 1.8g

UGH. I thought I was finally done making links. Thats a GREAT idea! $10 shipped? Serious? Damn, I wish I would have been watching carefully. I would have been all over that.

This is awesome! Just what I was hoping this thread would turn into.

[Erik D_lux]

Originally Posted by losikid

I've considered doing a weight overhaul, just never really any inspiration for it. Although the way you talk i may put my lipo on my servo so i can mount my elecs on the skid instead of on a elec plate i made on top of the chassis making it more top heavy,

If I had MOA I would even go further with cutting my chassis.

Can you put the electronics on your links? That would be super sick to have close to zero weight on the chassis.

I seriously thought it would be idiotic to place my lipo on my servo. I had to do it just to know. I think the reason it actually made it better is because my rear end used to roll me over if it got too sideways. Now that its so light all I have to do is watch what my front end does. If it is not close to rolling, my car is not close to rolling. Does that make sense?

Moving all my weight forward made my car a climbing machine!

[Erik D_lux]

Originally Posted by djjiz

What body are guys running with the battery on the servo?

My stocker already bottoms out and judging by the dents and chunks out of my servo case I'd hate to expose my cells to that abuse

You can see my bug body. I had to raise the body quite a bit which I didnt like either. Seems like it paid off though.

I use Gunners body mounts which are very adjustable. That $2.50 (shipped) for his mounts is by far the best bang for the buck I have spent on this car.

[djjiz]

Originally Posted by Erik D_lux

You can see my bug body. I had to raise the body quite a bit which I didnt like either. Seems like it paid off though.

I use Gunners body mounts which are very adjustable. That $2.50 (shipped) for his mounts is by far the best bang for the buck I have spent on this car.

Yea.. I'm a little slow I see the bug now

The mounts look pretty sweet. You ever weigh those?

I run a screw into each cross brace and so far so good.

[losikid]

Originally Posted by Erik D_lux

If I had MOA I would even go further with cutting my chassis.

Can you put the electronics on your links? That would be super sick to have close to zero weight on the chassis.

I seriously thought it would be idiotic to place my lipo on my servo. I had to do it just to know. I think the reason it actually made it better is because my rear end used to roll me over if it got too sideways. Now that its so light all I have to do is watch what my front end does. If it is not close to rolling, my car is not close to rolling. Does that make sense?

Moving all my weight forward made my car a climbing machine!

No motors are in the way of putting elecs on. Only worry i have it my lipo being beat till it pufffs, i have a heatsink on my servo now and well a couple of the fins are already bent in, i can just imagine what would happen to a lipo.
Oh also i read somewhere, i think on one of the team losi build threads that the softer springs will help keep your rear and from flipping you over like you described