• Welcome to RCCrawler Forums.

    It looks like you're enjoying RCCrawler's Forums but haven't created an account yet. Why not take a minute to register for your own free account now? As a member you get free access to all of our forums and posts plus the ability to post your own messages, communicate directly with other members, and much more. Register now!

    Already a member? Login at the top of this page to stop seeing this message.

krawlfreak

I wanna be Dave
Joined
Aug 21, 2008
Messages
2,641
Location
Having fun again...
HERE WE GO AGAIN.

i have been working on this chassis for some time now and it is finally to a point that i feel it will be a force to be delt with.

the chassis shares many of the fundamentals of the BJ series of chassis that have been proven to hold their own, time and time again, with some of the top chassis on the market.

i feel this one will be no different!

the aptly named "SECRET AGENT" will be a slightly different feel from the BJ series of chassis. there are some added benefits to this design, but at the same time you give a little to get a little.

the Bj series is a very easy chassis to set up and extremely "neutral". small adjustments on that chassis are not quite as critical. the "secretl agent" chassis is gonna be a bit more of a tuner's rig meaning you will notice small changes in setup more dramatically than the BJ.

what i am gonna do is not really a build thread but a disection thread. i will go through every exact measurement from the truck that you can view in the two video's.

these video's show the capability this chassis has.

enjoy

<IFRAME height=720 src="http://www.youtube.com/embed/vKZ24vQVKUY?hd=1" frameBorder=0 width=1280 allowfullscreen></IFRAME>
<IFRAME height=720 src="http://www.youtube.com/embed/6dzwdPxOqHU?hd=1" frameBorder=0 width=1280 allowfullscreen></IFRAME>


ORDER YOUR "SECRET AGENT" HERE
.
.
.
.
.​
 
Last edited:
Re: Krawl's "SECRET AGENT"

now to answer the most basic questions

weight rtr:
( this is a medium average, my dh tire combo is an 1oz heavier than my slw combo... this is with one of each)
IMAG0991.jpg


here you can get a good idea of the forward bias (weight wise)
IMAG0992.jpg


ride height:
fully drooped
IMAG0987.jpg

average ride height
IMAG0988.jpg


wheel and tire combo weights:
.9 DH's fully loaded
IMAG0994.jpg


front slw
(i will reveal how i get an slw to that weight and still use the same foams with no effect to the foam performance using some new foams from eddie at crawler innovations)
IMAG0993.jpg


rear slw
IMAG0995.jpg


width front:
out side of tire buldge
(dh's with 335's and slw's with 600 hubs are almost the same)
IMAG0989.jpg


rear:
(slw's with 600 hubs) appears narrower only because of shave side lugs

IMAG0990.jpg



now we will get the wheels off...

wheelbase:
fully drooped
IMAG0983.jpg

fully compressed
IMAG0984.jpg


average ride height
(like all my chassis if set correctly you will be running 12.5 max legal limit at ride height)
IMAG0985.jpg


weight without wheels:
IMAG0997.jpg
 
Last edited:
Re: Krawl's "SECRET AGENT"

now we will get into the link lengths and bias.

to take advantage of the forward bias this is where it will get critical.

not every link kit is the same


most are based on a 50/50 setup, meaning the chassis is centered in relation to the 12.5" wheelbase.

here is an example of where mine sits and is what all my link measurements will be based on.

note:
this setup is not for everyone! it suits my driving style and i can drive through some of the reactions that this setup is going to cause. i am not saying there is not a great benefit to this setup but again give some take some when it comes to overall performance.


if you want a little less forward bias you can move center back approx: 1/8" to 1/4" before adversely affecting chassis performance due to shock angles.

now assuming 6.250" as center in relation to the 12.5" wheelbase you can visually see where my "center" is.
IMAG0998.jpg


link lenghts are as follows and all measurements are eye to eye.

front lowers:
123.75mm

front uppers:
120mm

rear lowers:
140.5mm

reur uppers:
140.5mm


now the amount of bends and degree of bends is going to effect the starting lenght of the link.

now starting positions for mounting points is as follows (assuming you are using the vanquish products link mounts which is highly recomended)

front axle:
vp-top hole

front chassis:
3rd hole up

rear axle:
vp-top hole

rear chassis:
3rd hole up

upper links at the chassis are spaced .125" between chassis and rodend

my rear lowers are also moved up to the shock mounting tab on the vp upper axle case as well as spaced in .125" between the mount and the rodend. you can see this in the pic below.


bottom view.
IMAG0982.jpg
 
Last edited:
Re: Krawl's "SECRET AGENT"

shocks:

everyone has their preference....and here is mine.

i prefer a larger shock and spring with an internal/external limit to stay away from coil bind and the effects it has on rebound.

many different shocks can be used and like i said it is all personl preference thats suits driving style.

i figure the best way to get acurate info will be to measure the eye to eye overall/compessed distances and the actual stroke.

here are mine as follows:

FRONT:
axial xr shocks

preload 8mm

internal limit of 3mm
external limit of 10mm

fully extended length.
101.9mm

fully compressed length
85mm

actual stoke 17.8mm

rear shocks:
axial xr shocks

preload 10.5mm

internal limit none
external limit 13.1mm

fully extended length
107mm

fully compressed length
89.5 mm

actual stroke 17.39mm


the spacing where they are mounted to the chassis can effect different characteristics as well.

mine are spaced 7.15 mm (revo ball end) off the chassis and are 63mm apart center to center of the upper shock mount

chassis mounting location for the shocks is as follows

front:

2nd hole out from center


rear:

2nd hole out from center


a quick recap photo

IMAG0981.jpg


springs and oil will vary depending on driving style, weather and terrain.

i run 30wt f/r and run a 1.0 spring f/r
 
Last edited:
Re: Krawl's "SECRET AGENT"

Nice write up so far, I appreciate the info. "thumbsup"
I cannot wait to get mine, I want to try and get all of the electronics on a front motor mount and keep my batt on the front axle.
Where can one get those bitchin lockout weights?
 
Re: Krawl's "SECRET AGENT"

front slw
(i will reveal how i get an slw to that weight and still use the same foams with no effect to the foam performance using some new foams from eddie at crawler innovations)


Please do! :mrgreen: And VERY impressive crawler! "thumbsup"
 
Re: Krawl's "SECRET AGENT"

Nice write up so far, I appreciate the info. "thumbsup"
Where can one get those bitchin lockout weights?

the tractor supply store. they are just 5/8" collars drilled out slightly to fit over the vp lockout. they set srew on and are about 1.5oz each.

i will be trying 2oz in each rear slw to get the weight farther out"thumbsup"
 
Re: Krawl's "SECRET AGENT"

I know your a big fan of the BC's, have you tried any of the taller pin tires like the C.I blocks or khaos. I tried BC's first but found the taller height of the khaos to be advantageous, just wondering what your opinion is on the matter.
 
Re: Krawl's "SECRET AGENT"

I know your a big fan of the BC's, have you tried any of the taller pin tires like the C.I blocks or khaos. I tried BC's first but found the taller height of the khaos to be advantageous, just wondering what your opinion is on the matter.


i have not.

i really like the b/c's. they have taught me to slow my driving as well as search for the line rather than trying to muscle my way through courses.

i did run 6' rovers on my berg for some time, the larger tires have there place for sure but they are advantages,in my opinion, only in certain areas or individual courses.
 
Re: Krawl's "SECRET AGENT"

Great chassis and review/tech!

Might be a dumb question but will this chassis be offered in a berg setup?
 
Re: Krawl's "SECRET AGENT"

Great chassis and review/tech!

Might be a dumb question but will this chassis be offered in a berg setup?
thank you.

the chassis is definately not xr specific. as with the bj4.2 it will cross over just as well.


the xr is just my weapon of choice and the foundation i can offer the most insight on.
 
Re: Krawl's "SECRET AGENT"

Kinda bummed taht none of the vides had "Secret Agent Man" playing over them...

Looks like a great setup.

Does limitng the xr shock that much affect overall articulation? 10 & 13mm seems a bit excessive.
 
Re: Krawl's "SECRET AGENT"

thank you.

the chassis is definately not xr specific. as with the bj4.2 it will cross over just as well.


the xr is just my weapon of choice and the foundation i can offer the most insight on.

I'll give it a go with some berg axles then.

Thanks.
 
Re: Krawl's "SECRET AGENT"

Planning on shaving and clipping the pins on those front tires? Also go ahead and let the cat out of the bag on the foam not being effected by internal weights. I may have to try my BC's again, they are clipped but I never shaved them, wondering if I should.
 
Re: Krawl's "SECRET AGENT"

not at all.
IMAG0999.jpg

IMAG1000.jpg


everyone thought i was crazy limiting them on my bj4.2 also....like i said the video is proof of the performance.

Yeah on second look, the fact that the shocks are laid down so much allows for good articulation even with such limited shock travel.

My first tuber had hugfely laid down front shocks and exhibited the same thing. it basically only needed about half of the available shock travel to reach full articulation.
 
Re: Krawl's "SECRET AGENT"

That is BY FAR the sickest self shot crawl vid I've seen & easily in the top 3 of ALL crawl vids. The rubble bouncing off of the lense, killer POV's, sick lines...NICE brother.

That is defintely a nice lookin chassis. The lines are clean & precise & I'm excited to see the build threads start poppng off.

Nice work. "thumbsup"

J.D.
 
Re: Krawl's "SECRET AGENT"

Yeah on second look, the fact that the shocks are laid down so much allows for good articulation even with such limited shock travel.

My first tuber had hugfely laid down front shocks and exhibited the same thing. it basically only needed about half of the available shock travel to reach full articulation.


they are actually not any more laid down than the bj series of chassis.


That is BY FAR the sickest self shot crawl vid I've seen & easily in the top 3 of ALL crawl vids. The rubble bouncing off of the lense, killer POV's, sick lines...NICE brother.

That is defintely a nice lookin chassis. The lines are clean & precise & I'm excited to see the build threads start poppng off.

Nice work. "thumbsup"

J.D.
Thank you.

Videos have kinda become a new hobby.
 
Back
Top