XB4 Shock Springs

[Lee1972]

Sorry if this has already been covered in a thread already but are dot springs stiffer than stripes and is the higher the number the stiffer the spring?

[neallewis]

Stripes are progressive (they get stiffer as they are compressed)
Dots are linear throughout the compression.

I couldn't get on with stripes when I tried. I ran mine on AE big bore springs.

I'd say run a stiffer rear spring than kit for more traction and to stop collapsing, over rotation and grip loss on low traction surfaces.

yes C=n where n is larger, stiffness increases.

[Allan1875]

Stripes are progressive (they get stiffer as they are compressed)
Dots are linear throughout the compression.

I couldn't get on with stripes when I tried. I ran mine on AE big bore springs.

I'd say run a stiffer rear spring than kit for more traction and to stop collapsing, over rotation and grip loss on low traction surfaces.

yes C=n where n is larger, stiffness increases.

As quoted stripes are progressive, dots are linear. Higher the number of dots, stiffer the spring. I have a chart on my home PC that i have converted to lbs.

The bit I have highlighted in bold, i personally wouldn't be running a stiffer rear spring on low traction, I'd be softening the rear spring to stop over rotation, the rear spring on the XRAY by kit is already at 2.28lbs from memory which is firm enough. On low traction like grass or polished floor, i tend to come down to the 1 Dot rear although I am planning to try AE springs on the car soon. Stiffening a car up tends to increase rotation at least from my testing as the car leans less, therefore bites less.

Neal - Not sure if you were running the same AE Gray as Nathan was on the rear of his XRAY but they are ever so softer than XRAY kit springs.

[neallewis]

As quoted stripes are progressive, dots are linear. Higher the number of dots, stiffer the spring. I have a chart on my home PC that i have converted to lbs.

The bit I have highlighted in bold, i personally wouldn't be running a stiffer rear spring on low traction, I'd be softening the rear spring to stop over rotation, the rear spring on the XRAY by kit is already at 2.28lbs from memory which is firm enough. On low traction like grass or polished floor, i tend to come down to the 1 Dot rear although I am planning to try AE springs on the car soon. Stiffening a car up tends to increase rotation at least from my testing as the car leans less, therefore bites less.

Neal - Not sure if you were running the same AE Gray as Nathan was on the rear of his XRAY but they are ever so softer than XRAY kit springs.

I did run the greys yes, and they were too soft for low traction tracks. Going softer made it worse! Going harder stopped the collapse mid corner and kept the rotation constant (no instant spin out) and so the corner traction, rotation and apparent grip was better.

I've just gone through exactly the same with my BMAX4-III. I'm now running the hardest spring i can, and its spot on on low traction, but switching to a soft spring kills it into a spinning out wreck. I think its all about getting the right spring weight for the weight of the car. I struggled for a year with the xray trying to get it work on the low traction indoor tracks what we have here, gym floors. Tried everything. more weight, less weight, light diff oils, heavy diff oils, shock towers, wishbone hangers, roll centres, no roll bars, roll bars (never tried super stiff on rear though to be fair), all the spring/oil weights you can imagine. Stiffer spring is better for the car I had. I ended up running AE yellows (their heaviest) on the low traction indoor tracks, which was the best I had had it. I tried all the xray springs available at the time (1dot, 2dot and 2 stripe). the progressives were awful.

Changing to another car instantly helped, but i went through the same issue to start with. Going to spring weights much heavier than AE yellow rears has helped so much. I'm currently running Yokomo Orange which are much heavier, and I've got blacks and purple to try next, but possibly they will be best for high grip astro. Saying that i know someone who runs purples (heaviest) at York indoors on a BMAX4-II.
I think had I tried this on the xray then it would have been much better. It's gone now, so i can't.

I guess my point is, with the car, you need to try find what works for you, don't take "lighter spring is better for low traction" as a gospel rule. it isn't.

[Allan1875]

I did run the greys yes, and they were too soft for low traction tracks. Going softer made it worse! Going harder stopped the collapse mid corner and kept the rotation constant (no instant spin out) and so the corner traction, rotation and apparent grip was better.

I've just gone through exactly the same with my BMAX4-III. I'm now running the hardest spring i can, and its spot on on low traction, but switching to a soft spring kills it into a spinning out wreck. I think its all about getting the right spring weight for the weight of the car. I struggled for a year with the xray trying to get it work on the low traction indoor tracks what we have here, gym floors. Tried everything. more weight, less weight, light diff oils, heavy diff oils, shock towers, wishbone hangers, roll centres, no roll bars, roll bars (never tried super stiff on rear though to be fair), all the spring/oil weights you can imagine. Stiffer spring is better for the car I had. I ended up running AE yellows (their heaviest) on the low traction indoor tracks, which was the best I had had it. I tried all the xray springs available at the time (1dot, 2dot and 2 stripe). the progressives were awful.

Changing to another car instantly helped, but i went through the same issue to start with. Going to spring weights much heavier than AE yellow rears has helped so much. I'm currently running Yokomo Orange which are much heavier, and I've got blacks and purple to try next, but possibly they will be best for high grip astro. Saying that i know someone who runs purples (heaviest) at York indoors on a BMAX4-II.
I think had I tried this on the xray then it would have been much better. It's gone now, so i can't.

I guess my point is, with the car, you need to try find what works for you, don't take "lighter spring is better for low traction" as a gospel rule. it isn't.

That is a fair point, i will test your theory out when i get a chance as i also race on a lot of gym floors. Been running the car 2 Dot, 2 Dot on them and it's been good.

I ran my car to hard at Kiddy R1, Ran 3 Dot, 2 Dot but it wasn't handling the bumps properly at all so had to soften it.

[neallewis]

That is a fair point, i will test your theory out when i get a chance as i also race on a lot of gym floors. Been running the car 2 Dot, 2 Dot on them and it's been good.

I ran my car to hard at Kiddy R1, Ran 3 Dot, 2 Dot but it wasn't handling the bumps properly at all so had to soften it.

Astro tracks are bumpy, the AE greys were good, but the grip was higher. The indoors tracks are mostly flat and bump free. Stiffer spring works. I guess oil weight and pistons also have an effect here, a heavier oil also helps resist the roll and helps stop the collapse I was having, but not what you need on bumpy tracks. You would see it collapse, the un-weighted wheel would spin up and the car spin out. Again with the xray I took advice that said to go lighter on the diff oils for low traction, but i found that when a wheel goes unloaded in a corner, with the lighter oil the power is instantly transferred to the light wheel causing it to spin up, and the car over rotates. And so it goes on...

A bit off topic now for the original question, but like I said I struggled for a year to get it to work for me. An expensive process with the xray really, I tried it all and had al the option parts. The last parts were the +2 rear wishbone hangers and new wishbones, which didn't help with low traction at all. So I sold it. its a great high grip car, and was awesome on the RHR clay track too. Just junk (for me) on low traction indoors tracks like Batley and York.

[Lee1972]

Thanks chaps for the replies a lot of good information cheers :thumbsup: