Looking at the Petit spring rate chart and it shows the HPI silver that is so popular is really soft. Is this correct? Looking to grab a few spring for tuning, all i have is the kit reds right now
http://site.petitrc.com/reglages/1-1...ingChartv2.pdf

Hey,
try new progressive set from SMJ,
last year i was happy with schumacher green....

metal gear bevels
 

does anyone tried the metal bevel gears part no. 54428 in TRF 419 gear diff,.

does it work and
how I have to shim theses
thanks
Harry

Whats wrong with the stock plastic gears?

short story:
last year i bought my first Tamiya (419) --running modified Gforce 4.5T boosted, kit Diff damaged all 2 runs -or badly version- it was killed during first lipo run.

so read a lot- ed clark pointed out that i have to use XRAY -orings- no problems- no leaking :D
run over winter 13.5T blinky a lot of runs (over 100 lipo runs) without any problems and leaking!:D

Yesterday I run again modified, but with big 0.3mm shim under pin. after 10runs it broke down again. I want to fix this. dont know why- had small crash sideways without breaking parts.

so I had ordered the metal one long time ago and now want to know who has some experience with them.
thanks
Harry

Can someone explain the benefit of wide G blocks in front? It seems to be the defining feature of the 419X but I'm not exactly getting what it does...

Become finally my time again to 419 to test if the weather cooperates this week :sneaky:

For the first time asphalt this year.

So what broke in the diff? Why do you suspect the plastic gears are at fault?

One recommendation is that you use the metal cross shafts and shim the gears properly. I don't think the problem is with the gears themselves but with rubbing plastic against plastic.

Also, the Xray o-ring is thicker. With a shim under the gear and the Xray o ring, you are changing the relative positions of the gears (you are bringing everything closer together) hence you're generating more heat.

I tried Xray o-rings when the diffs appeared a long time ago (actually I tried them on the TRF417 diffs first), but gave it up for this reason. I prefer to use metal shims under the gears. This frees them up and takes away the heat by preventing plastic on plastic rubbing (for the same reason I recommended metal cross shafts).

My suspicion is that this is the reason of all the diff blow-ups. Also (just in case you didn't) sand lightly the back of all gears, just to make sure they're perfectly flat and smooth (and a smidge thinner).

Leaking can be stopped using a good quality silicone grease like that made by Dow Corning (sticks like shit to a blanket).

Try and see.

Sticks like shit to a blanket! Lol! I just got some of that Dow55 the other day. Going to rebuild my diff using it. Also I use the ARC silicone o-rings for there diff. Fits way better than Xrays. No binding!

With the Xray silicone diff joints you need to use 0.1 shims underneath.
0.2 seems to bind the diff.
I made 4 diffs this way with 0 problems.
The 0.1 shims are includrd in the Ta05 diff maintenance set.
The wider front gives you a more confident feeling when driving the car. I put Fblocks (made by the RcRacer) on my son's car and since that change he really likes the car and got some good results with it.

thanks for advice

but my suspicion is more torqure with modified motors and if the small bevels "go out" under torque the bigger bevel -GV2 is going in and the inner pin damage the back side of the bevel (GV 2). next time I will test 0.1 shim for big bevel and 0.2 shim for the small bevels

but I have 4 diff made with different shiming and I searching the best durability for modified....

So thanks to DavideJoos for the hint with XRAY O ring and the 0.1 shim.
@RCRacer hints are awesome: LP towers - low shocks and F susp part with shapeways working great

but honestly I can´t understand why the TAM-diff´s are not made properly from Tamiya, without any testing shims and O-rings etc.....

Is this on a Mod car or a stock class car. From personal experience the steering gets too diluted with anything wider than D D front for stock racing for almost any track on any surfaced for any track at least for the ones I have experience with. Not sure how the combination of lower roll center and wider front blocks will work on 17.5 blinky or 13.5 blinky cars.

On a stock car, in both 10.5 and 13.5 blinky. The car is really balanced, especially with a narrower rear (xa and d).

Couple of things... the Shapeways 3D printed blocks are not very durable. What I mean by this is after an afternoon of running with them (12 - 5 minute stints) @ Tamiya USA, the holes where the A arm shaft fits into the block starts to widen leaving play from side to side as the shaft hole elongates under driving. The part does not allow for the A arm shaft ball/cups that are designed into all aluminum toe blocks, just a hole bored into the printed block for the shaft to fit in. I was concerned about this when I put them on and an afternoon of crash free driving proved this to be the case. Not sure why they didn't print the part with provisions to hold the ball cup in them so the A arm shaft would be nested inside, but they didn't do it. The way they are designed, you'll get an afternoon of driving out of them (IF you don't hit anything) before the parts wear to a point where there is too much play from side to side creating a combined toe differences of a least .5 degrees. Not sure how durable they would be for those who crash a lot.

Also the new 419X showed up at the Tamiya track last Saturday. The 419X uses "G" blocks up front (FF/FR) as the only option to be built from the box! Yup G blocks! :eek: The driver running it loved the car from the first battery pack. Equally as fast as his 419 on his first battery and he got faster as the day went on. Many new changes to the design of the 419X to not be able to compare "apples to apples" but the car looked very stable and easy to drive. The wide front end is a trend used by a few of the mfg's including Yokomo.

I ran the F/F block arrangement on my 419 and it still provided plenty of steering corner entry, mid corner and exit, but smoothed the turns out enabling me to drive the car harder. I was running a 13.5T preparing for the Reedy Race. Sadly, I only purchased one set of the Shapeways blocks and since they "print to order" there is about a two week or more lead time for replacements. I'll be going back to my aluminum blocks for Reedy.

Reedy Race ready :tire::deathstar:tire: