Dex410 Big bore v Small bore - Whos using what?

[Allan1875]

Was looking through some setups online and noticed some people still using small bores at most tracks.

Was curious what everyones thoughts were on this? I have big bores as they came with my v3 but i am considering getting a set of small bores to try.

[OneKiwi]

With the 410 I am trying the SB with BB springs and all the BB holders/retainers etc. From what I remember last time I drove it it worked well.

I have even tried the SB and found that it reacted a little quicker, but I do like the BB as it feels a little lazier and not so twitchy

I haven't driven for a while (heart transplant 4 weeks ago) but hopefully back out driving within a couple of weeks.

You don't need a heap of springs for the SB either, Jörn runs DB/LB everywhere

[Allan1875]

Originally Posted by OneKiwi

With the 410 I am trying the SB with BB springs and all the BB holders/retainers etc. From what I remember last time I drove it it worked well.

I have even tried the SB and found that it reacted a little quicker, but I do like the BB as it feels a little lazier and not so twitchy

I haven't driven for a while (heart transplant 4 weeks ago) but hopefully back out driving within a couple of weeks.

You don't need a heap of springs for the SB either, Jörn runs DB/LB everywhere

Does Jorn still use SB aswell?

Get well soon dude, heart transplant! Jeezo.

[ridgeracer]

Using SB with BB springs and like it very much, but Im going to try BB with 2 holes front and 3 holes rear this season also

[Allan1875]

Originally Posted by ridgeracer

Using SB with BB springs and like it very much, but Im going to try BB with 2 holes front and 3 holes rear this season also

I've just bought SB's off a guy here and will give them a blast this weekend. Have only raced my rango once so far, so be interesting to see the difference.

[kartstuffer]

I prefer SBs on my 210 and BBs on my 410 dont know why but the work better for me.

[Allan1875]

Originally Posted by OneKiwi

With the 410 I am trying the SB with BB springs and all the BB holders/retainers etc. From what I remember last time I drove it it worked well.

I have even tried the SB and found that it reacted a little quicker, but I do like the BB as it feels a little lazier and not so twitchy

I haven't driven for a while (heart transplant 4 weeks ago) but hopefully back out driving within a couple of weeks.

You don't need a heap of springs for the SB either, Jörn runs DB/LB everywhere

Just bringing up my old topic to add some info to see what other people think.

In my opinion, the big bores that i've been running since getting the car are definitely not as responsive, even when running 6x1.2 pistons front and back. This really got shown up yesterday at our first regional on an extremely bumpy track, my big bores couldn't really keep up on the rear. I managed to soften the front enough but even on 25w oil on the back the rear was still struggling to ride the bumps.

I will be moving to small bores this weekend for the extra responsiveness as most of our tracks are grass and fairly bumpy although the one at the weekend is by far the bumpiest. I think the big bores is suited better to smoother tracks.

If you fill a big bore and a small bore with the same oil and similar or identical pistons, then compress them, you will see the massive difference in response which is understandable due to the extra oil in a big bore having to pass through the piston.

[Chesty]

I found my DEX410V3 (big bores) was significantly better when I ran drilled pistons.

On a bumpy grass track I used 6 hole kit pistons drilled out 1.5mm & it was pretty good. I did drill a set out to 3 x 1.7mm but never got to try them - may have been even better...

I'm sure there's a comparison chart on Petit RC.

[Allan1875]

Originally Posted by Chesty

I found my DEX410V3 (big bores) was significantly better when I ran drilled pistons.

On a bumpy grass track I used 6 hole kit pistons drilled out 1.5mm & it was pretty good. I did drill a set out to 3 x 1.7mm but never got to try them - may have been even better...

I'm sure there's a comparison chart on Petit RC.

Thats definitely something I might try, it in theory should compensate for the extra oil.

[KennyClark]

My car felt good on the big bores.
Change the pistons and it will be fine.
Your car looked like it had too much pack.

[Allan1875]

Originally Posted by KennyClark

My car felt good on the big bores.
Change the pistons and it will be fine.
Your car looked like it had too much pack.

It did, the holes are far too thin for the bumpiness we were contending with.

[drobec]

How do you guys run BB springs with SB shocks? What needs to be changed? Only bottom spring retainer? And what about collar?

I want to use some hard white springs but don't have BB shocks, it would be perfect if BB spring can be used with SB shocks, 100 Euro saved in my pocket.

[OneKiwi]

I have used the SB retainer and collet (top and bottoms) but ride height (spring space) is affected as you are adding less room for the springs, if that makes any sense at all.

[drobec]

Are you sure SB bottom retainer will hold BB spring? Isn't its diameter smaller than diameter of BB spring? And the same with collar.

Why there should be a less room for a spring? Sorry but I can't imagine that.

I found on Petit that you need BB bottom retainer and probably a collar from Traxxas (TRA3768) which you simply put on SB collar, is anybody using it like that? And yes, in this configuration you have slightly less space for spring but you can adjust it with moving SB collar a bit upwards.

[ridgeracer]

I use BB bottom retainer and SB+BB collar from Team Durango on my SB shocks. Works perfect.

[OneKiwi]

Yeah sorry BB stuff on the SB shocks

[kartstuffer]

Originally Posted by ridgeracer

I use BB bottom retainer and SB+BB collar from Team Durango on my SB shocks. Works perfect.

I use this and it's fine.210 & 410. Small bores just work better for me.
My son (10) prefers big bores , his car is slower to react but his hands are faster and he is now faster than me as well.