During compression, if the pressure in the bladder is less than the pressure generated above the piston, the oil under the piston can cavitate or draw air in through the o-ring seals. So building shocks with maximum pressure in the bladder is theoretically better. http://www.kaztechnologies.com/wp-co...m-Kasprzak.pdf

Also, recent empiric RC car shock data also supports the use of foam to increase bladder pressure.
https://sites.google.com/site/rccarengineering/home

Maiden run for my 419 last night and I am very impressed. Fastest I've ever gone around my home track and it's very balanced. Compared to 417V5, the rear end is less stuck, allowing the car to be more responsive. Only a 0.16 spread in from my best 5 average to best 15 average, so it's clearly easy enough to drive for my skill level.

As I mentioned earlier, all settings are kit, however I am running 3,000 oil in the diff and 450 in the dampers. Kit springs, even. I finally managed to get hold of a set of HPI Silvers, but didn't get them in time to try.

Phil.

FYI....

HPI Silvers are about 1 full step (6.5 vs 7 coils of 1.5mm wire or 300 vs 270g/mm) harder than the stock 419 springs (which are close in rate to HPI blue)

If you go by C rating, I believe they would be 2 steps harder. 2.7 (Silvers) vs. 2.5 (Tamiya Red).

The calculated spring rate for the new TRF spings.

Yellow - 19.2 lb/in
Black - 17.0 lb/in
Red - 15.3 lb/in

Yellow (1.5 x 5.0)
Red (1.5 x 6.0)
Black (1.5 x 6.5)
42278 TRF LG Dia Spring set


May want to double check that
Looks like Black is softer than red ?

I was referring to the "steps" that Tamiya tend to take - half turns.

But C rating?

That's how xray and x-gear rate they springs - yes?

My understanding was 2.7 = 270gf/mm

Refer : http://www.petitrc.com/reglages/1-10...ingChartv2.pdf

Mine (42278) are;

Yellow (1.5 x 6.0)
Black (1.5 x 6.5)
Red (1.5 x 7.0)

See pictures....

http://www.rctech.net/forum/13771100-post706.html

Just the info I needed.

I have springs from 418+extra springs, 419 and tb04evo6 springs and the TRF bigbore spring set. All mixed up. Had no idea which was which because some of the paint chipped off.

After going through all of them it seemed like the yellow ones were hardest. But I also had 2 yellows that seemed different, the yellow with heat shrink and yellow ones with paint.

So I take it the yellows closest to the holygrail of asphalt hpi silver springs. I've been using Ride Red springs so far but will try both of these yellows next since I only run asphalt.

Thanks Cplus

Yeah the 418 springs are an oddity. They have the same black pearlescent finish as the new TRF set (42278) but the rate completely different.

The springs in the evo6 and the 419 are definitely same as 42278.

Evo6 = 2*black and 2*yellow
419 = 4*red

Sorta, it's the black from the 42278 set that are closest to HPI silver (6543) and/or Ride Red (28013).

It's the yellow from the 418 bonus that are also same wind. But you can't buy them to make a set of 4.....

All are 6.5 coils of 1.5mm wire, and, in theory ~300gf/mm

The HPI and Ride springs are wound in the opposite direction to Tamiya. This may possibly effect the "feel" - which is what is commonly said of the HPI vs Ride Red despite them appearing near as identical.

No dramas!

I tend to use this chart as it seems a little more relevant today:
http://www.reflexracing.net/RSD-Univ...art_ep_58.html

Also, if you look at something like a Spec-R spring with a similar wind count, a 6.5 coil is 2.7. I am "assuming" the wire diameter is 1.5 and the length is the same though, but the chart above makes me think it's close. If I'm wrong, I'm sure someone will correct me. :D

- JV

For the most part that chart agrees with petitrc - which was updated in January this year.

But yeah, they both state align with, say C2.7=270gf/mm - look at the xray stuff (which measures up as it is rated - unlike the HPI stuff!)

I have a tip for the leaky dampers used Tamiya X-Ring 42214.

Yesterday I was driving back to carpet and I am disappointed in the quality of the new C-Hubs I've reinstalled. Have 2 ruined and will reinstall the old cheap one I used before.

The Front Axles must often change or the Rear Axles too and so on :rolleyes:

I understand that Rheinard for every application gets new cars :sneaky:

Curious which bumper are you guys running?

I stopped breaking the C Hubs on my TB04 Pro 2 after I changed stock bumper to the Xray Hard Foam Bumper

http://www.amain.com/xray-hard-foam-bumper/p393916

I'm using the same bumper now on my 419. No broken C hubs thus far.

Thanks again for the clarification cplus.

Does that X-ray foam bumper line up well with the body and mounting holes?