Stability AND maneuverability, how to?

A lot of us want more stability, without giving up too much maneuverability. Long decks, harder bushings, and lower baseplate angles, increase stability, but at the cost of maneuverability. How can we have our cake and eat it too? Maybe you’ve got short board that is too twitchy, but you like the turning radius. Or maybe you’ve got an Evo that’s rock solid, but you’d like to be able to take a turn without merging into a new lane. Let’s hear some ideas?

My untested thoughts

  1. trucks with more rake, and lower baseplate angle Rake supposedly makes the center feel dead, but the extreme-lean feel lively. Seems perfect, a stable center, but plenty of turn at the limits

  2. softer bushings/cone bushings, cranked down hard Maybe softer/cone bushings will not get incrementally stiffer by very much as you lean from mild turn to extreme turn. That way you can crank them down a ton to have stability around center, without cutting off the limits of lean?

  3. tkp rear Tkp in the rear adds trailing caster (like shopping cart wheels) which should theoretically add more return to center

3 Likes

TKP makes things twitchy, as a larger percentage of the total turn range is available in the early part of the lean. RKP is opposite and more, uh, linear.

Oh and Ronin. Queen pin trucks seem to have this solved. Too bad it’s so hard to put a motor on the reasonably priced and available ones.

EDIT removed the babbling about slalom as I think I’m misremembering

3 Likes

My setup is probably not fine-tuned as well as it could be, but having quality bushings that match your weight and riding style makes a helluva difference (without having the trucks as tight as possible…).

Ask @Alphamail to share his wizdom and advice… :ok_hand:t3:

5 Likes

Flat washers. They don’t constrict bushings as much allowing for more lean and less rebound that will snap you back into a wobble.

Wedging front and dewedging rear is a great way to have your cake and eat it too!

About rake… I never liked it. I mean, I did… But it was never just right. We used to run Randals flipped in the rear for negative rake and unflipped in the front. Without wedges, this basically acted like wedged front dewedged rear. It was great for downhill and going fast but never really ideal for maneuverability. Ideal for me has turned into just having a neutral rake hangar. There are no odd inconsistencies with progressive or regressive turning feelings, and wedging serves it’s purpose taking the place of positive and negative rake. By all means, don’t just listen to me… I haven’t tested raked trucks like this in well over a decade and I’m just going off my impressions from back then. Test and report back to us what you find.

Unless you are using bushings designed to be cranked down (krank bushings?) It’s not a good idea to crank down soft bushings, they usually just get torn up that way.

1 Like

Is this true? Tkp trucks have a ton of positive rake, and take is typically said to make the center more neutral

1 Like

Interesting idea. I think stiffer bushings, in a less restrictive bushing seat may be something worth exploring

I’ve found the riptide Krank bushings (magnum and cannon rear, magnum and FatCone in the front) with flat washers to be very good. I tried 90A throughout to start but that was too stiff for my weight, now I’m on 86a up front and 86a boardside 90a roadside at the back. I’m 76kg on tb218’s.

And I’m saving up for some SurfRodz!

2 Likes

Truck geometry to me is like dark magic. But, TKP usually feel very divey compared to RKP. And stronger return to center.

2 Likes

Same impression here. I think surfrodz TKP’s wide open bushing seat has a lot to do with this. To bring another variable into the equation, surf keyz on their TKP drastically change the feel as well.

1 Like

@Alphamail this sounds like something you can help with?

1 Like

TKPs are not twitchy in the center. They have high amounts of rake, meaning that they don’t turn all that much until you put enough weight past a certain point. TKPs feel twitchy because they ‘flap’. Basically they have an inconsistent turn feel as you begin to go faster. They can still be stable, but their unpredictability is the reason they’re perceived as twitchy.

If you only want stability, just run a split angle and call it a day. You can still turn sharply, but the board will feel dead due to the lack of rear responsiveness.

Into OP’s second point about cranking down soft bushings. Don’t. You rapidly increase the precompression and create a lot of rebound. You end up with precompression twitch. The rule of thumb is to use the hardest bushings tightened down as little as possible. RipTide’s APS and WFB formulas play very nicely into this tuning ‘rule’, since you’re not supposed to tighten them beyond flushing the nut on the kingpin. @Alphamail can probably explain this concept better than I can.

Small amounts of precompression can be good because this allows you to better engage the bushings to the truck hanger. However too much precompression is not a good thing.

Setup the front to have the maneuverability you want, setup the rear to have the stability you want.

Thats how you do it.

Also, precision helps here, as do upgraded bushings.

Wedges are your friend.

The fundamental difference between TKP and RKP trucks is the intersection of the king pin axis and the pivot axis. The RKP truck’s axis’ are perpendicular to each other and which results in a more stable and predictable geometry since the axle path tracks a straight line The TKP’s axis’ are not perpendicular which results in a far divey turn initiation and a curved axle path that is defined by the combined pivot axis’. RKP’s roll where TKP’s rock and roll. Add a loose bushing seat or undersized bushings adds a third motion I call “wag”, which is the worst thing you can experience.

RKP’s benefit greatly from wedging and dewedging to achieve a maneuverable and stable setup. if you are starting out with 50 degree base plates, there is not much need to wedge the front further, just dewedge the rear. Minimum dewedge is 5 degrees to start feeling a real difference and it is up to you how far you want to go.

TKP’s rarely benefit from wedging the front so I normally leave the front alone and dewedge the rear, 5 to 10 degrees is normally enough

To make either of these work, you need to compensate for the greater amount of leverage the rear truck has over bushings compared to the front with different washer setups, bushing size and shape, durometer or bushing compound.

4 Likes