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Old 01-09-2015, 12:25 PM   #6346
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Where are you guys getting the center diff from?
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Old 01-09-2015, 01:11 PM   #6347
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Originally Posted by rchogfan View Post
Nothing to do with your spring problem but I suggest u add a bit of weight to the front left side of that thing.
Thanks, I kind of planned on it, just wanted to get it on the track as is, then I'll be sticking a few weights on there to try it out.
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Old 01-09-2015, 01:22 PM   #6348
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Originally Posted by Boz View Post
If you do screw the ballend all the way over the thread it may bind up the pivot ball in the ball end. Then the suspension will feel sluggish, very pack feel to it..

Sorry I cant help you on your spring play question. I run a 20mm ride height and have no spring play. I use 3dot fronts, 1dot rear. I still running saddles packs. More info required.
Front or rear?
What springs are you using?
What is the total length of the shock?
Thanks, I know about the ball binding, as it happens on my Teknos so I paid attention for that.

Both springs are a bit loose, stock springs so 3 dot front and 2 dot rear
lengths, from center of eyelets, are 75 and 88mm

Originally I had 1mm downstop shim in front and none in rear and left a little thread exposed on the ends per the basic clay setup, After I upped both downstops(2mm/1mm) and turned the ends on, the rear play was taken up, but still have about 1mm of slop on the spring in front when fully extended. I do have the large spindle bushing on bottom, so I may just swap it to the top, raising the spindles a bit, which would allow me to turn the collars down a bit to get the same ride height........
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Old 01-09-2015, 01:36 PM   #6349
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Originally Posted by TV View Post
Droop shims, shock length and the shock end all have no effect on the ride height, or where the collars rest. If the car and the springs are new, I'd just run it a couple packs and see if the springs settle a bit.
I don't think you're understanding the main issue I was trying to describe, it isn't really ride height. It is that when I set the ride height to 18-19mm, then allow the shocks to fully extend off the ground, the spring becomes loose, with a couple mm of play from top of spring to the collar, because the shock itself extends farther than the uncompressed spring. The droop shims, shock length/shock ends most definitely have an effect on this, along with the length and stiffness of the uncompressed spring, which I just checked and measures at just under 45mm.

With the lower weight of shorty, perhaps I need the softer springs as well. This would mean that I would have to run the collars down a bit farther to achieve the same ride height, and hence take up the "slack" when fully extended.......

Edit: I just swapped the bushings on the front spindles to put the spindles in the upper position(larger bushing on bottom side), this dropped the front end, so I had to go a few threads on the collars to get it back to 18mm, and now the springs do rest/press gently against the collars when shocks are fully extended. I'll run it like this tomorrow(for the first time), and see where I go from there. Also added 14g(for now) to the left front to compensate for the servo on the right a bit.
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Old 01-09-2015, 01:57 PM   #6350
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Where are you guys getting the center diff from?
I called RC America directly since no one else even seems to have the part number in their system.
They shipped it the same day I ordered it and it got to me the next day. That said I think they ran out a day or so later.
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Old 01-09-2015, 02:28 PM   #6351
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Where are you guys getting the center diff from?
Call rcamerica and buy it over the phone. I had mine in 3 days shipped from Texas. It will be nice to talk some setup ideas with you kp. I'm really excited to get this car dialed. The 44.3 was pathetic and it was the fastest I have ever given up on a car!
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Old 01-09-2015, 03:00 PM   #6352
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Hi kevinpratt823

I'm glad you knew about the ballend thing. I see to many driver screwing them on too far and forgetting to see if the pivot ball still can move.

Ok so it's only a few mm of movement. What TV is saying is that the spring need to settle if they are brand new. I was coming from another angle, that you may have built something wrong, which it sounds like you haven't.

When I'm running a new car after it's first run, the ride height normally sags a few mm's. Mine can go from 20mm down to 17/18mm when running a new set of 1dot springs. Then I have re set the ride height, which means screwing the collars down a few more turn. I be honest, I have never notice the floating spring before. But I do set mine car to 20mm.

All good. You can always push your car up and down on the bench for 10min if you are bored. lol
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Old 01-09-2015, 03:04 PM   #6353
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Originally Posted by yunowill View Post
Hey guys just a quick question/concern .

First things first I have been into rc for many years and also competitive racing at my local tracks . I have had many cars before this XB4 and have bleed many shocks in my time . I love the Xray it is the best 4wd buggy I have ever had and raced with .


My question is no matter what I do and how I bleed the shocks there is always a squishy feeling right at the top of the shock when I compress the shock . I am building my shocks with zero rebound . I have gone through a few bottles of shock oil trying to get a nice shock . Is there something that I am missing to figuring out how to get rid of that squishy noise in the shock when its fully compressed or almost about to be fully compressed ?

If anybody knows please share

Thank you
I was kind of surprised at how loosely the o-rings/bushings fit in, the lower cap really doesn't squish anything down compared to most other shocks I have dealt with. I also found that after the initial bleed, when I pump the shock hard a few times before I do the final re-bleed, they almost seem to take a little air in.......Just build 'em and run it I guess, the air mixes right in with the oil after a few strokes and it still does what it's supposed to, but I will definitely be checking/re-bleeding them often until I get more familiar with them.
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Old 01-10-2015, 01:48 PM   #6354
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Ran the buggy today, felt pretty good. Broke a spindle and carrier though and the shop didn't have it. Trying to find some good aluminum ones and I don't see a ton out there, anybody know anything about this D-Hawk stuff? Is it just cheap Chinese crap?http://www.ebay.com/itm/like/1910918...466&rmvSB=true
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Old 01-10-2015, 02:29 PM   #6355
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Originally Posted by Boz View Post
Hi kevinpratt823

I'm glad you knew about the ballend thing. I see to many driver screwing them on too far and forgetting to see if the pivot ball still can move.

Ok so it's only a few mm of movement. What TV is saying is that the spring need to settle if they are brand new. I was coming from another angle, that you may have built something wrong, which it sounds like you haven't.

When I'm running a new car after it's first run, the ride height normally sags a few mm's. Mine can go from 20mm down to 17/18mm when running a new set of 1dot springs. Then I have re set the ride height, which means screwing the collars down a few more turn. I be honest, I have never notice the floating spring before. But I do set mine car to 20mm.

All good. You can always push your car up and down on the bench for 10min if you are bored. lol
Thanks Boz. I think I got what TV was saying, but the springs were too short for the way everything was set up, I'm pretty sure they wouldn't get longer after breaking in. Ran it today at 18mm, and I likely will be going up a bit in height, placing an order for some springs to try also, among other things.
Thank you both for the feedback.
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Old 01-10-2015, 03:25 PM   #6356
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I've had an issue getting this buggy 14' to drive right, put about five packs through it with a 8.5 making minor changes and can't get the rear to stop washing out on every corner. Its almost like a 2wd and I've tried what had been suggested and i appreciate the help. So far I've tried loosening the slipper and run the motor and esc with no timing advance, still not working for me. It's currently the clay stock setup with the correct tires. The rear has almost no droop and the front has tons. Something isn't adding up to me. I took the motor and esc out to try a different setup to only find out the outdrives on the slipper are already notched. I've never seen outdrives notch so quickly with such little drive time. Any suggestions?
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Old 01-10-2015, 04:18 PM   #6357
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Somebody suggested I post some pictures to make this more clear, here it is.

In reviewing and typing this, I noticed that the basic clay setup I was going by also specified 2-dot fr/1-dot rear springs, this would make up the difference, as the softer springs would have to be compressed farther down with the collars to achieve the same ride height, and they would thus return fully with the stroke of the shock and maintain tension on the collar.

Notice in the basic clay setup, it says to put the larger spindle bushings "down", this effectively lowers the spindle on the carrier, and as a side effect less preload is required to achieve a desired ride height, which is 18mm according to sheet. The basic instructions lean you more towards assembling it with the bushing in the up position in the left picture but shows both options on the right, so I'm curious if anybody is running it in the down position as I tried to.
The same sheet specifies 1mm downstop shim in front, 0mm in rear. The instructions tell you to screw the shock ends on leaving 1-1.5mm of thread exposed. Now, with all of these things done, you are left with a shock that can extend pretty far, and the geometry of the car in a way that the shock shafts to be slightly more compressed to achieve the same ride height as it would if the bushing was on top.
Now, when backing the collars off enough to achieve that low ride height of 18mm with the stiffer kit springs, they end up pretty close to the top when the car is sitting. Now when the car comes off the ground, the arms drop, the shocks extend fully, (maybe even needing a little assistance from gravity at the end), and by the time the spring fully expands there is still a few mm of out-travel left in the shock. The result was the gap between the top of the spring and the shock collar, and it left the spring floating loosely over the body, with no remaining tension.

If you all built the kit with more than 1mm/0mm downstop(limiting the extension of shaft), or with the larger spindle bushing on the topside of the carrier, with softer springs, or a higher ride height(all requiring more spring/collar preload), it would have given/taken enough to make the difference and the spring would remain slightly compressed under full extension.

The moral of the story I guess is that you cannot build the car to the basic clay setup with the springs that come with it. You either have to get softer springs, or make compromises with downstop, spindle bushings(roll center), or higher ride height. I hope I didn't cause confusion or clutter the thread with this, but I figured somebody else is bound to encounter it and maybe it will help.
Attached Thumbnails
Xray XB4 thread-sam_0564.jpg   Xray XB4 thread-sam_0563.jpg   Xray XB4 thread-sam_0562.jpg   Xray XB4 thread-sam_0561.jpg   Xray XB4 thread-sam_0559.jpg  

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Old 01-10-2015, 08:37 PM   #6358
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Originally Posted by kevinpratt823 View Post
Ran the buggy today, felt pretty good. Broke a spindle and carrier though and the shop didn't have it. Trying to find some good aluminum ones and I don't see a ton out there, anybody know anything about this D-Hawk stuff? Is it just cheap Chinese crap?http://www.ebay.com/itm/like/1910918...466&rmvSB=true
You running with bigger cars? I have crashed a whole bunch, never broken a spindle in the last year.

4 arms, 2 pins, ring and pinions and a rear bulkhead.
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Old 01-10-2015, 08:43 PM   #6359
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You running with bigger cars? I have crashed a whole bunch, never broken a spindle in the last year.

4 arms, 2 pins, ring and pinions and a rear bulkhead.
Nope. Temps were not much above freezing, so that doesn't help, but I was just practicing on a brand new indoor layout, jumped a triple a touch too far and landed into the outside pipe just as it starts to bend for the next corner.

The kicker is that I had bought spare pins and arms and had those in my bag, but no spindles/carriers because it didn't sound like many broke them. Maybe just a freak thing.
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Old 01-10-2015, 08:43 PM   #6360
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Originally Posted by kevinpratt823 View Post
Ran the buggy today, felt pretty good. Broke a spindle and carrier though and the shop didn't have it. Trying to find some good aluminum ones and I don't see a ton out there, anybody know anything about this D-Hawk stuff? Is it just cheap Chinese crap?http://www.ebay.com/itm/like/1910918...466&rmvSB=true
meh, alum parts are not the answer
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