Putting the CR01 on a diet.

[OSRC]

I love my CR01's. With a bit of work, they can easily hang with the Axials, and they are something different. Mine are the only 2 in our club, and I'm always looking to increase performance. This is my original, bought off backorder when they were first released, and has seen many different set-up along the way. I'm very happy with it as it stands, and while it gets around pretty good, there's always room for improvement.

This trucks biggest downfall imo is its weight. It's a pig to be honest. I always run with one rig and keep another on my back, and I always know when this one is strapped back there - my back lets me know loud and clear. Most of the weight is up high, so I've had to add a lot down low to offset. This means less run time, more wear and tear (on my third set of stub axles) and a sore back for sure. So, it was time to put this rig on a diet.

I've tried this on my "smaller" CR, and it worked very well, so it was time to go under the knife with the big one as well. First off, time to replace the heavy complicated chassis with something simpler and lighter.

I cut out new plates that use the stock geometry out of 2mm 6061. I had thought about moving the trans mount up, but i like the spring/shock set-up as it stands, and I spent a long time getting the links where I wanted them, so no need to mess with anything,


New chassis plates weight in..stock setup was 95g. Not bad. Combined, I went from 190g total down to 102.


I also had swapped in an aluminum skid along the way, and while this one is among the better of them, it is still more weight above the center line...and aluminum seems to catch on the rocks far more than plastic. Went back to the plastic one, and ground all the ribs off to make it smooth. Went from 32g to 15g.


Put it all back together. Just had to mod the battery tray a bit to fit the new set-up - everything else bolted right on. I did trim up the battery tray where possible as well to lose a few more grams:




Overall chassis-wise, I dropped from 222g total down to 117, a nearly 50% decrease. While 105 grams doesn't sound like much, the difference is astounding. Since the weight lost is above the axle centerline, the COG dropped a ton - I can feel it on the bench right away. I didn't get to test it out as it was a monsoon yesterday, just crawling around the basement, it felt much more stable and surefooted. Consider this a success - can't wait to get it out on the rocks!!

[Syncrog60]

Love how people are still spending time modding the CR.
Plenty of life in the CR yet

[OSRC]

Very cool and easy platform to modify. Sure beats just bolting on parts. Nice to have something unique on trail days as well.

[raceeng18]

Am I seeing things correctly, are your shocks mounted to the links? I had a Clodbuster that used that type of shock mount. After market of course. Thanks.

[OSRC]

No, on the axle. Same as this pic of an older set-up

[raceeng18]

Originally Posted by OSRC

No, on the axle. Same as this pic of an older set-up

Thanks for the photo's OSRC, nice looking CR01

[Scottd9990]

So how did she work out on the rocks? I have a CR01 I am thinking of putting on a diet as well. I like your shock setup and plan to copy that too. Let us know how she works now please????

[6sharky9]

I spy Axial Shocks

[Scottd9990]

Yea, I saw that as well!! I have a nice set of RC10T Alum Shocks that I am looking to put on my CR01. Very nice setup here. Just want to know how well it works before I copy it!!

I did some work last night on my stock canti-lever setup limiting the flex a bit with fuel tubing over the stock shock shafts to give me a bit lower stance. Seems to work ok, but less flex. I am not much of a rock crawler, more into trail running.

[Scottd9990]

Here is what mine looks like.

[Scottd9990]

I like the flat iron tires as well. I have a set on my CC01 Mog and they are great tires.

[OSRC]

Originally Posted by Scottd9990

So how did she work out on the rocks? I have a CR01 I am thinking of putting on a diet as well. I like your shock setup and plan to copy that too. Let us know how she works now please????

Well, the rocks in question are under a foot of snow, so it will be a while till i can get out there.

As far as the suspension, I've run this set-up for quite a while, and it's good. Super stable - rides very flat and only flexes when needed. I like it a lot. Only complaint is it is a bit "tall in the saddle" - I could switch to the barrel springs, but then I'd lose the center clearance. Got some more tinkering to do, but the overall premise is so far very good.

As far as the chassis mods, have also done another CR01 with a lightweight chassis and it has made all the difference in the world. Assume this will do the same.
CR01 Custom chassis build

[Scottd9990]

Originally Posted by OSRC

No, on the axle. Same as this pic of an older set-up

Do you think using the stock springs and separate shocks is better than going with coil over shocks? What have you found to be best?

I removed my canti-lever system last night and went with straight (Associated SCT) shocks/springs. These are the nice associated alum shocks from the short course trucks. Seems to work pretty well, but I see everyone using the stock springs from the CR01 and separate shocks. What's the best way to go???

Thanks!

Scott

[OSRC]

There is no "best" - it's what works for your budget, skill level, driving style, etc. Nothing wrong with the shocks and springs you are using at all - question is do YOU like their performance? Don't worry so much about whatever everyone else runs, find a set-up that works for you and run with it.

The set-up above works the same as a standard coilover. Might add a bit of weight, but operates exactly the same. I just think it looks cooler.

[DRW-FJ40]

Looking good OS. I put that cheezy RC4WD 4Runner body on mine last season & drained my interest. Put my old beat up FJ40 body on & I'm back.

Don't really know why I like the CR so much... probably not worth trying to figure out.

I do miss betty.

[OSRC]

Thank you sir - Betty may yet live, figured out I have enough spares to build a third truck.

[DRW-FJ40]

Originally Posted by OSRC

Thank you sir - Betty may yet live, figured out I have enough spares to build a third truck.

The wife must be pleased... Mine always gives me that look when I mention building another...

[OSRC]

I just order them in parts. much smaller boxes, easier to smuggle them in the basement.

Was poking around last night, think I have everything but a radio tray (easy) and body mounts (not so much) If this snow ever ends and I get a break from clearing off our property, maybe one day I can build something out of it.

[Osteo]

OSCR - so with your 2 custom frame rails, which truck do you find crawls better? I keep coming back to your pictures and am so close to attempting it with my truck. I've been poking around trying to find a Junfac Joker, but they are discontinued as you probably already know and I don't mind tinkering myself - to boot, pretty sure I have the aluminum in my workshop already as well!

My buddy got frustrated with building his CR01 so he picked up a Wraith so not I have 2 CR01's. I was going to build the 2nd up for the wife, but now I think I'm going to keep it for myself!

[OSRC]

well, I've built 3 of these chassis, and they ALL perform better than stock. It's all in the set-up really, my "bug" crawls like a champ, the above chassis (now a jeep) it not as capable, but still not bad at all.

With the bug, I took the trans mount plate and moved it up quite a bit. Eventually swapped in an Axial trans to lower CG and ran a semi-droop set-up. This basically lowers the CG while increasing the center clearance. Tricky with the CR chassis.



The above chassis (in the build thread above) is no longer in use at the moment, I re-cut it, lengthened it out, and tucked up the trans mount plate about 1/2 inch. Not much, but didn't want to stray too far from the stock geometry so I could still run the barrel springs. More of a stock looking rig (ish) and certainly wheels like it. I could get much better performance if I swapped out the springs/shock set-up for something more conventional, but I like the look, and watching it twist around out on the trails never gets old.



Can see the differences here if you squint hard enough - bug chassis is much lower overall and more compact. Same WB and width on both rigs:



Have build threads on the both floating around:
Jeep: 3rd time's a charm
Bug: CR01 Custom chassis build

Making the chassis are pretty easy to do, all the components for the most part are the same width (except the batt tray) - just use the original chassis as a template and cut away!

Hope that helps