ShortCourseOnly

Like Salad said, stick with the C-hubs and get STRC upgrades. I just got home from testing my latest set-up and it is really stable. I have STRC C-hubs, stock steering knuckles and replaced the upper arms with a traxxas camber link. The front end still dives a little with 50wt single hole stock rear shocks up front. I shorten the springs about 1-2mm and limited the droop. I will be rebuilding the shocks with AE#3 and 70wt oil for Saturday. The truck is dialed except tires. I was using M4 Bow ties and they did good but I expect a soft barcode to grab better.

The PBS suspension is lighter which is nice but the truck has too much weight in the rear with a 550 motor. I saw Krios Jammin in person tonight and it is clean. It handled pretty good but the real test will be this Saturday's race. I expect 20+ entries in 4WD SCT with at least 8 Jammins.

I will check my weight bias after I rebuild my HV 4.5 motor. The Front endbell bearing fried tonight. Better on a practice day then on race day for sure. I ran that motor every week hard for 9 months. I cleaned it once about 4 months ago so I am really happy with the Novak 550 motors. I hope to get a Ballistic 550 soon.

annonymous

iTrader: (21)

cool, thanks for the imput guys

short course: does going to a "rear" tower in the front with only a upper camber link opposed to the stock "wishbone" affect durability or suspension function? i was planning on doing that, but i am hesitant about converting a truck that may have not been designed for that. the stock Front suspension is a bit flexxey, but i guess the alum. parts remedy that?

thanks!

and i also need a novak ballistic haha

Wldmoose

iTrader: (3)

Spork... can you elaborate a little on how you and SCO did the upper A-arm mod? I tried it awhile back but had some nasty torque steer so I went back to the stock A-arms. I would much prefer a straight turnbuckle though.

Did you stick with using the sway bar collar on the upper pin to hold the rod end in place or find some other newfangled way of doing it? Which TRX PN#s? So many questions....
I run the SNR 4mm towers and STRC hubs and knuckles too.

SaladFork

iTrader: (9)

I've just kept running it as is... The only thing I have done since the mod was add the STRC front hubs, it's been solid. I ran it three times at the track since without issue. I ran it on 3S with a Tekin 5.5 550 and didn't notice any torque steer. I beat the crap out of it last time I was at the track. I do plan on getting a set of SNR towers to replace the Elite ones. But have put the Jammin on hold till after the holidays while I get my heli flying fix and finish my Ten T/e conversion.

Here are a few pics. I use the collars from one of my other Jammins and it fits the pin, tighten it down towards the front and off you go. I am using after market titanium turn buckles, but other then that it's all stock parts. Looks ghetto but has worked fine for me. I got sick of busting upper arms, I swear when I was on the 1/8th scale track I was going through two a day, sometimes not even on a hit, it would just crack. Indoor it's not as bad...





Here is the Ten T, this is how the Jammin should be IMO.

ShortCourseOnly

My upper arm modification looks exactly like the Ten T. I do not have the hinge pin or the upper rear pin retainer installed. I am using SNR towers. I used the stock Traxxas Slash camber link #3644. It comes as a kit with the large flange screws which I installed exactly like the Slash. To install the Slash camber link I had to grind the captured ball a little to fit into the C-Hub. Other balls could be used but the stock ball is to small for the traxxas rod end. The other end required that I drill the plastic bushing through so that the Traxxas large flange screw could push through for me to add a nylock nut to the other end. Works great so far. I will post any changes that may come from this modification.

I also installed STRC C-hubs at the same time. I don't notice any bump steer. The truck handled better and steering was more crisp. I hope to have pics sometime to share.

I was having issues with the stock upper arm turnbuckles. I replaced them with the 4mm Lunsford part which worked a while but in the end the plastic is too thin to hold well.

Lazer Guy

iTrader: (1)

+1
The 4mm link was not a fix for me ether

Yesterday I ran 4 packs out at 15min. each with the 4 upper link set up I did in post #8158.
I put it back on my setup station this morning, everything is right where I put it.
It felt good not having to worry about breaking that stock Y-arm !!!!

I drove it hard and hit everything but Chris' bad azz whammer jammer
Man I wish I could drive like you.

Now I need the T-Bone bumper.

Racecrafter

iTrader: (25)

The major problem with just an upper link on the Jammin is the caster will always vary.

The steering becomes vague and inconsistant. The lower arm is not strong enough to hold the steering hub at its setting. However it's great for those who bash to get more flex and be a little more forgiving until the lower arm breaks.

Kev1966

iTrader: (3)

Is there any major differences between the Hyper 4x4 and the Jammin 4x4? I read about both kits and to me they are identical. Anyone know of any differences?

Kevin

jrock32

iTrader: (12)

Has any one found other springs that fit the stock jammin shocks?

ShortCourseOnly

While I do understand what you are stating I can say that I did not feel this in my truck. Steering was great and with the Aluminum C-Hub it is more stable and less sloppy that with the stock set-up. We'll see what happens over the next few months. I will post if I break something.

temtruck

are you running stock traxxas camber links or titanium and what length are they

ShortCourseOnly

I am running Stock Traxxas steel camber links. The turnbuckle is 39mm and the overall length is 69mm center-to-center. I had to shorten the links to set the proper camber so they are 1-2mm too long.

I fixed a few things and weighed my truck in race ready form (battery, body, etc) and it came in at 2855 gm. which is 350 gms heavier than ROAR spec, of 2505gms. That's like 10 oz. but I can't really see reducing much more weight. I could use the Traxxas Aluminum camber links, Lundsford Ti hinge pins and remove more material but the performance of my truck is solid and I don't want to risk durability. I am considering the SNR Csrbon chassis or the new OFNA 7075 chassis to reduce weight. I may even test a Ballistic 8.5/13mm high torque rotor combo which is about 100gms lighter. I do love the 550 motors though.

My weight bias front-to-back is 48%/52% which is pretty good for the stock layout. I did not check side to side much but when I placed my Speedo behind the battery box It seemed to balance it some. I did see a potential to move the battery forward a little and my Novak Kinetic is small enough to mount forward on the chassis. It may help reduce wire length to the receiver. I think I am set really good for my driving style.

Upgrades to do:
1) STRC Steering Knuckles
2) Xtreme RC Carbon steering top plate

I am also looking at the rear chassis brace to see if I can improve cornering some. Many 8th scales are eliminating the twisting control of the rear brace to allow more flex in corners. The stock Jammin SCRT chassis brack is solid plastic attached with 4 screws throught the chassis plate and firmly sandwiched into the diff bracket. It does provide some resistance to twist. I baught a old style RC8 rear brace (Thanks to Krio the suggestion) and it looks like it will work with some modifications to the Diff Bracket. This old design has captured ball ends which only applies support in the compression and no twist control. I plan to test the effects of the rear chassis brace this Saturday. I will post my results.

annonymous

iTrader: (21)

SCO: just a heads up on the motor plan, i had my truck at, exactly, 2505g with a ballistic 7.5 high torque motor, and it would not push it! i tried everything! it was very frustrating, it came off at 235 no matter what i did, every time
- just a thought

ShortCourseOnly

What gearing did you use? Was it a 13mm high torque rotor? A 7.5 is 5800Kv. You'd have to use an 11t pinion to match the speed of a 8.5 5000Kv with a 13t.

Your issues are noted. I fixed my 4.5 550 so I should be OK.

RustyRC

iTrader: (25)

Anyone tried this motor? 4t/4800kv


http://www.amainhobbies.com/product_...otor-4T-4800kV