Dlux Berg Build

[Erik D_lux]

On the narrow side for me right now. I would like to go a touch narrower but everything is in the way in the front. On the rear, I get some undesireable effects if I go much narrower.

10.875 front
10.625 rear

[Crawllife]

Just saw your vapor question from last week Erik. They are 30t type R. Freekin amazing with my micro sidewinders.

[d-wray]

Nice video, so how much does a Dlux super lite berg weigh. rig looks good Erik

[tapped-out]

It's so light he added helium knuckle weights.

[Harvo]

Originally Posted by d-wray

Nice video, so how much does a Dlux super lite berg weigh. rig looks good Erik

You might be surprised

[Erik D_lux]

Yeah...... shes a big fatty.. LOL.

The axles are super lite, the car, not so much.

With Sedonas I am looking at 4lb 7.5oz rtr. Pretty hefty by todays standards. I hope to be adding big ole chunk very soon.

[SkaldidDog]

Originally Posted by Erik D_lux

Yeah...... shes a big fatty.. LOL.

The axles are super lite, the car, not so much.

With Sedonas I am looking at 4lb 7.5oz rtr. Pretty hefty by todays standards. I hope to be adding big ole chunk very soon.

She's pleasantly plump. I like fat trucks and I can not lie....

[Erik D_lux]

I got a couple of new things to mess with...

First off, I decided to get some HR gears.

My first problem is that Brood has ruined me. I used to be able to drive my car and not put much thought into the motors and the way they react. Good enough used to be good enough. Now, I have run all his arms and it has really opened my eyes to how tiny of a change can have such a big impact. Different style arms, pinion size, start up etc,..

One reason I went to the HR gears was for their lower gearing. I think having more torque would be a good option and with the Berg, gearing up is much easier than gearing down.

My second reason for the swap was that I want a better pinion. Again, I feel like I am more in tune with the car now. If something is not 100% perfect, it bothers me. I have noticed that I am swapping out the RR pinions more than ever as they just dont run the same after some run time. I think they are too soft and I am wearing them out. With no other option for the Berg, the HR 2nd gear will let me move into 48p pinions which will let me get a harder pinion and many more options. For whatever reason on my super, the HR gears are noisey and dont seem to run super smooth. I am not sure why this is but I hope its not a problem with this car or at least I hope they break in a bit faster.

The gears...



What I am really after....

[Erik D_lux]

NERD alert!

Be forewarned that this next post is extremely nerdy, technical and boring. You may want to skip this post.

I got the MIP bypass pistons.



IMO, this could just make the Big bore an even better shock.

I made myself a video as I knew this would be a confusing change, especially when there is zero information out there on them. Thanks to JeremyH for posting up about them. I never even knew they existed.

I wanted to post the video to help anybody who might be getting into them but also, more eyes on what I am doing would be great. I think I got the fronts into the ballpark but I am really confused and not sure on the rears. Worst case, I think the fronts feel much better and there more tuning that can be done, I can always throw the standard setup on the rears again.

I know quite a few people with the opinion that small changes dont matter on our crawlers. Some even run without shock oil, which blows my mind. In the video you can see the differences that all the changes to the shocks make.

Dlux MIP shock tuning - YouTube

[TEDROCKZ]

Keep on working with them! Take some of the homework out for the rest of us. I believe there is a good set up in these somewhere. Gonna take some time and different opinions.

[Erik D_lux]

Thats the plan.

Its a rough road when there is zero information and lots of options. 10wt or 100wt? Thinnest shim or thickest? I didnt think it would be a big deal but having never driven a car with adjustable compression and rebound, it gets confusing really easy when you have no idea what range you should even be in. It makes me realize how easy tuning your shocks with a single oil was.

[Erik D_lux]

To spark some discussion on shock tuning... I wanted to see if anybody had thoughts on the basics.

How do I want the shock to function on the front?

Stiffer compression than rebound
Stiffer rebound than compression
Same compression and rebound

What about the rears?

Ideally, I think the bypass pistons need valve stacks on each side of the piston. Right now, the above needs to be figured out before I even start tuning. The way these are designed as of now, depending on how you have the valve stack, either compression or rebound will always be less/more until you flip the valve shim. Also, one thing I am not liking is that if I dont like the amount of compression and I change that by upping the shock oil a touch, now my rebound changed along with it. Again, I think valve shims on both sides with a constant shock oil is more ideal but I didnt engineer these things so I may be asking too much?

I think the first things that will have to be figured out is the above question (do you want more rebound or compression on the front/rear?). The next thing you have to figure out is almost an exact ratio of compression to rebound.

[SkaldidDog]

Hey Erik,

I see where you are going with this and I can appreciate where it may take you as far as improvement goes. Two questurevations:

If you are implying that the contents of your shocks are responsible for the differences in handling and climbing, do you think the shocks are cycling sufficiently in these tests to satisfy you that your results are solely the result of varying the contents of the shocks?

The very fine tuning line you are walking may be difficult to stay on if other variables are contributing to the results more than the shock contents (air/rock/tire temp/humidity, tire/rock wear, rubber deposition, experience with the climb, frustration/hope resulting in less or more focused driving).

I'm here with you in that there might just be a sweet spot somewhere. My concern is that it may all go poof as soon as the conditions changed. If anyone can sort this out you sure can. Now if you could repeat these thorough tests say on the rocks in AZ at the time of day you 'll be driving, that fine line will not be as fine.

J

[Erik D_lux]

Originally Posted by SkaldidDog

If you are implying that the contents of your shocks are responsible for the differences in handling and climbing, do you think the shocks are cycling sufficiently in these tests to satisfy you that your results are solely the result of varying the contents of the shocks?

I dont think I would say the shocks are cycling. I would say that the contents of the shocks change the way the car reacts though.

Originally Posted by SkaldidDog

The very fine tuning line you are walking may be difficult to stay on if other variables are contributing to the results more than the shock contents (air/rock/tire temp/humidity, tire/rock wear, rubber deposition, experience with the climb, frustration/hope resulting in less or more focused driving).

Without question what you said is true. If you watched the video, I felt that I knew the point where something besides the contents of the shocks changed. I dont know what it was. The place where I tested is some of the most un predictable rock I know of. For testing, it sucks but, it is the hardest rock to tune on and it will bring out the negatives in your car more so than anywhere I have ever driven. Its sort of like the St. George rock in a way.

AZ rock would be a good rock to test on too but I am just working with what I have.

Originally Posted by SkaldidDog

I'm here with you in that there might just be a sweet spot somewhere. My concern is that it may all go poof as soon as the conditions changed. If anyone can sort this out you sure can. Now if you could repeat these thorough tests say on the rocks in AZ at the time of day you 'll be driving, that fine line will not be as fine.

J

My idea was to tune then when I am done with that, tune and then tune after doing some tuning. Kinda like "The Price Is Right" where they guess the value of something. Start low, go way to high etc,. etc,. until I learn how they work/feel and then hopefully I am in the ballpark and can slow down the tuning.

If you have an idea for a better way to test, I would love to hear it. How did you come to the conclusion that what youre running is the best for you?

[TSK]

On the fronts, I would think you would want softer compression and slower rebound. That would allow the front end to dive quicker and unload slower.

in the end though, I believe the traditional piston setup would be much more forgiving and predictable. At some point, with the bypass piston, you will find it difficult to fine tune it to your exacting stadards as you cannot tune the compression or rebuind individually. Tuning for either will affect the other, whether favorable or adverse

[MR.VERTICAL]

Have you thought about using the RPM shock kit.











Two Stage Shock Pistons (Medium-Heavy Dampening)

[Erik D_lux]

Originally Posted by TheSCorpionKing

On the fronts, I would think you would want softer compression and slower rebound. That would allow the front end to dive quicker and unload slower.

Seems to me that I want the opposite.

Say you hit a small bump, or even hop in the front. I am imagining that the front is now floating in the air and with almost no weight on the front its having a hard time getting planted on the rocks. I could see this happening over and over every time you hop or hit a bump?

Originally Posted by TheSCorpionKing

in the end though, I believe the traditional piston setup would be much more forgiving and predictable. At some point, with the bypass piston, you will find it difficult to fine tune it to your exacting stadards as you cannot tune the compression or rebuind individually. Tuning for either will affect the other, whether favorable or adverse

If by "forgiving and predictable" you mean easier and a lot less work, I would agree, 100%. I think to understand and have tuning possibilities, an adjustable shock will be the future.

You can adjust the valve shim which will adjust either your compression or rebound depending on which side of the piston you are on and that will not effect the other. But youre right, if you adjust the oil you adjust both. Thats my biggest hurdle right now.

Originally Posted by MR.VERTICAL

Have you thought about using the RPM shock kit.



Two Stage Shock Pistons (Medium-Heavy Dampening)

I looked into them briefly awhile ago. Do you use them? I will have to research them again.

[Shaunkjar]

If you were out running a desert truck across whoops and nasty washboards, you would want a shock that compresses easily and is slower to extend. It allows the shock to absorb the bump instead of forcing the tire to do it or transferring the bump through to the frame. I may be mistaken, but it also slows the "rebound" effect on the body which causes endos in jumps. How this all transfers on a small scale into rock crawling, I'm not exactly sure. I think it would be the same and is the reasoning behind using a variable shock in the first place.

Softer up travel (compression) and slower down travel (rebound) should allow your shock to soak up the bump and keep the tire in better contact with the ground, rather than bouncing off the bump. If the rebound is faster than the compression, you get an opposing unloading of the spring and the body

As for front vs rear, it should technically vary by the sprung weight distributed there. Stiffer spring and heavier oil for the heavier end (if your sprung weight is any different front and rear), softer spring and thinner oil for the lighter side. It would be interesting to try the opposite in the rear so that as you bounce on an obstacle, your front shocks soften and lower a bit while the rear remains stiffer.

Of course I am open to correction on any of this. Speaking of that, DLux, you're big-time, you should call Robby Gordon or Shannon Campbell or some other 1:1 aficionado and see what they say.

For those wondering about these here is a link to a video giving an overview of these shocks: http://m.youtube.com/watch?v=VlruGyaM_uM

[TSK]

Slower compression and faster rebound would definitely cause the truck to bounce more upon impact and cause severe unloading making the hop even worse.

[Harvo]

Cool experiments. I know more about mountain bike shocks and suspensions than crawler shocks, but I think some of the principles apply. It would be nice if crawler shocks were externally adjustable like the ones on my bike (there's your next projet Erik)

On my crawler I try to tune all the hopping out with my tires and foam. All I need the shocks for on climbs is to make sure they stay in contact over irregularities in the climb.

I tune my shocks for quick response to sudden changes. Like when a rear tire drops off a ledge. If it falls too slow, it can lift the opposite corner and flip the truck. Or if the front corner takes a drop off a ledge, a very slow compressing front won't react quick enough and flip the truck. That's what I plan on setting my MIPs up for.

To answer your question, I think in the rear (for the situation in your video) would benefit from a quicker compression and slower rebound. The bounces are quick and that set up might get the shocks compressed quicker and hold them there to limit the bounce.

But really... what do I know Good luck. Hope to have mine in a few days.