FS2/Big bore setups

[RogerM]

I am getting more springs to measure this weekend ... I only have access to a limited range as nobody close to me runs a car with big bores on that I can borrow.

More info next week.

[SimonW]

I have to run at least 30wt oil in the back of my car with the standard pistons and yellow springs, how are you guys getting down to 22.5wt and not bottoming all the time ?

[/tobys]

What kind of shock length are you BB guys running?

I've got some new toys now(!) and they are built as per instructions (with the shorter top eyelet) but when the fronts are mounted on the car in my (currently) preferred outer wishbone location, I seem to have hardly any droop at all! Plenty of droop on the rear.

Must say though, they are lovely shocks

[RogerM]

I must say that I've never even tried the big bores in the outer wishbone hole. Part of the reason I am running Losi springs is to get me into the rate range where I can run in the middle hole.

I must however admit, as I've said to a few before, that I am keen to try them with the longer 46mm shafts in the outer hole to get more front shock inclination. The main reason I've not done that already is that we would then need even less piston hole area than we have now to keep the small bump compression damping in a similar ball park to what we are using!

Simon, if I put 30wt oil in my big bores with the standard 5 hole pistons on the back of the FS I'd have time to go and make a cup of tea before the shock rebounded!!!
As far as I can tell, with the exception of yourself, everybody I have spoken to about the big bores wants more piston hole area in the rear shocks to allow them to get use the 27.5-30wt oil range and still have acceptable rebound speeds.
Have a quick measure of your pistons, they should be 11.88mm diameter, my guess is that yours are significantly undersize for some reason!

[/tobys]

Roger, are you running the std Kyosho pistons that you have drilled yourself or something else (home brew for example)?

You also mentioned that you were building a chart to list the various spring rates - do you have anything you can share with us yet? I'm keen to see how the Losi springs compare to the Kyosho Xgear ones (if at all).

[Gayo]

Here is the chart I use, I made it from various sources I found online so it may not be utterly accurate though.

Rear :
K Pink 2.04
K White 2.10
K Gold 2.14
K Red 2.23
K Yellow 2.31
TL Red 2.60

Front :
K Pink 3.08
K White 3.22
K Gold 3.34
K Red 3.53
K Yellow 3.60
TL Blue 3.80
TL Black 4.10
Y Green 4.50
Y Orange 5.25
Y Black 5.40

K : Kyosho BB springs, TL : Team Losi BB springs, Y : Yokomo BB springs

[RogerM]

Yes, been drilling the standard pistons.

There was an issue with machine calibration on the spring chart so need to round up all the springs again and repeat. Sadly time is not my friend at the moment either.

I can tell you the Losi springs are NOTHING LIKE the rates on the packets but consistent. The X-gear springs are very consistent but it appears ALL the fronts are too soft for UK style tracks (obviously my opinion).

[/tobys]

The Yokomo springs look quite stiff in comparison then...I see that some folks are running the Yokomo Green which is described by Yokomo as Super Soft yet the chart suggests it is stiffer than the Kyosho and Losi springs...

[Gayo]

Yes it sounds weird, but the Yokomo springs are really harder, you can feel it in your hands, they are waaay harder!
For now I only have the Kyosho BB springs and the Yokomo blacks and I feel a huge gap between these. I am waiting for the Losi and Yokomo green and orange so I can test them.

[RogerM]

Something to do with the Bmax4 weighing more than a house????

I would suggest trying Losi green / blue on the front of the FS, X-gear red or Losi pink rear

Not the LT springs are a fair bit harder than it says on the packet or Gayo's table .... I'm still working on this BUT I have so little free time ... I bet I don't get to race off-road again till October

[/tobys]

Roger, do you have the p/n of the longer BB front shock shaft?

I ran mine out with kit pistons (35 Front/25 Rear Losi oil) with Losi Black/Pink springs and it wasn't bad - although felt like too much pack on the rear as it was quite jittery over smaller bumps.

Any idea which Losi BB spring is closest to the Yokomo Green?

[njc11]

W5184-04

At the oOple Race i ended up on Front 5x1.4mm 40wt AE.. Rear 5x1.45mm 30wt AE..

I now have the Tapered pistons to try.. so will report back once ive tried them..

[RogerM]

Toby do you mean the 46mm shaft? Shock shafts are the same as the standard shocks so length for length just order the same part number.

Yokomo Green roughly a Losi Blue (still trying to find time to post-process the results of the measurements to adjust for the calibration errors)

I imagine that the Losi Black would be way too hard, what was the low speed steering like?

I have found that with the standard pistons in the back 22.5wt AE is about as much as is usable.
I've tried drilled pistons in them, find anything over 5x1.4 in the rear too be too much the other way, for me the standard pistons are just about right for the front ... if anything I would be looking at smaller holes.
Nick likes a softer car than me so it is worth trying both setups to see what works for you mate.

[/tobys]

Thanks for the shock shaft info. Have you ever tried the longer RB5 shock tops on the FS2 shocks to give more droop? I'm keen to try longer shafts to regain the droop that I lose by using the outer hole on the wishbone - I've tried on a number of occasions to use the middle but seem to gravitate back to the outer...

I've got some Yokomo Green springs on order so will be interesting to see how they compare with the TLR Blue and Black springs I have available to me.

Low speed steering seemed fine with the Black springs (but I was using the outer wishbone hole) although the Astro track I ran on was mostly high speed with just a couple of slow corners. It was quite bumpy in places (being mainly a 1/8th Nitro track) and 25wt was the lowest I had! Even then it felt quite lazy...

Running the FS2 again this weekend and I'm armed with some tapered pistons of varying sizes so will try to get a better overall package.

I am having some issues with TLR Rear spring length (a bit too long) - I have virtually zero thread left on the adjustment collars available to me at the moment. Are the Kyosho springs shorter? How do they compare to the Losi rears?

[Gayo]

Originally Posted by /tobys

Thanks for the shock shaft info. Have you ever tried the longer RB5 shock tops on the FS2 shocks to give more droop? I'm keen to try longer shafts to regain the droop that I lose by using the outer hole on the wishbone - I've tried on a number of occasions to use the middle but seem to gravitate back to the outer...

By doing this, you won't have enough uptravel. You need a longer shaft or unscrew the eyelet a few turns.

[/tobys]

Thank Gayo

Saves me doing it myself only to find this out and then having to change it back!!

[RogerM]

Indeed, you can actually get to the point you start breaking things just by landing funny ... IMHO the cars only weak point is a slight lack of up travel, to that end I space my towers up by 2mm both ends and run shocks 1.4mm longer (unscrewed rod ends) .. works a treat!

I too have zero adjustment when running TLR rear springs ... there are some shorter lower spring seats from some other brands (Ansmann I think is one) so might well try them next time I am playing with setups.

[/tobys]

are the Kyosho rears shorter and how do they compare in rate - are they much softer?

[RogerM]

The Kyosho / X-gear rear springs are about 5mm shorter IIRC. I believe that the X-gear white is the same as a Losi yellow, X-gear red is similar a Losi Pink.

I say believe as there was a calibration issue on the machine when I measured all but the Losi springs and the few X-gears I have (which include the white so I'm sure on that one!).

It is only really the X-gear fronts that are soft compared to some other brands ranges.

[Gayo]

Here is my updated chart, made with a kitchen balance

REAR
K Pink 2.05
K White 2.10
K Gold 2.20
K Red 2.30
K Yellow 2.40
TL Red 3.00

FRONT
K Pink 3.19
K White 3.32
K Gold 3.42
K Red 3.57
K Yellow 3.69
TL Blue 4.25
Y Green 4.60
TL Black 4.80
Y Orange 5.25
Y Black 5.40

Indeed Roger, TL springs are way harder than what they claim, I wonder why
I need probably a rear TL pink spring and a front TL green to fill the gaps in my chart. I will update my findings when I get them.