Hi everyone. Recently I have been having a bit of confusion about chassis setup when it comes to wet/slippery/low grip conditions. I run an OTK, and I always loosen up the kart in the wet. This usually involves loosening the floor tray, loosening seat stays, and loosening the rear bumper. The thinking behind this is to try and get the chassis to flex more, creating more grip. Likewise in hot or over-grippy conditions, I will stiffen up the kart to reduce jacking and overall grip. I have now realised that other people who run OTK’s are actually doing the complete opposite to me - stiff in the wet and soft in the heat. Anyone with an OTK have any advice?
Yep, otk in low grip should be loosen up a bit. Front bar flat, front width you could play with for more turn in.
Otherwise third bearing loose, 139cm rear width and softer axle if you bother. I’d just run medium and increase pressures until you’re happy. No real magic behind it since otk works with standard setup pretty much all the time
As Lucas said, the baseline OTK setup works well in many conditions. For high grip, you should be stiffening the axle. For low grip or rain you should be going to a softer axle.
The stiffer axle will help settle the kart down when grip levels rise and keep it from rebounding too much and hopping.
The softer axle will allow more flex when the track is slippery and can’t provide enough grip and force to help the kart flex, and will make the kart squat and get traction easier.
You can play with other adjustments to fine tune but as far as axles go, those are the changes OTK recommends.
Wet weather OTK, depends on time avail to make changes. Here is what I do in order of time availability:
1). Bar vertical (opinions can vary here). Makes kart more pointy on entry but can make it push mid off.
2). Widen front
3). Narrow rear
4). Go more positive camber
5). Add 1-2 positions caster
6). Add 1/2 to 1 box toe out
4,5,6 are all done at same time…
7). Raise front and rear ride height
Usually if there is time to do 4,5,6 there is time for this too.
8). Go softer in rear axle
9). Add another rear strut (just because it is a change my son doesn’t like, so put it last)
My son is very tall, so we could often make due with fewer changes and still be much faster in wet than dry relative to field.
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