I decided to take a break from sorting out the swingarm alignment and move on to the rear suspension setup. I had five different single shocks on hand—from a big-wheel pit bike, through a KX250 motocross unit, and up to a Husky 610 shock. I measured each one and worked out their spring rates, then put together a simple Excel sheet with key dimensions like stroke and overall length.
For the first time, I tried using Google’s AI to help choose the most suitable shock and the best mounting position. I have to say, it worked surprisingly well. It felt like having a sharp, fast-thinking assistant in the workshop—someone to bounce ideas off and handle the calculations quickly.
Some parameters were already fixed: swingarm length, rear tyre diameter, the rearward limit of the lower shock mount (to clear the tyre), and a practical mounting height above the swingarm centreline. I also estimated a total sprung weight of about 200 kg (kart plus driver), with roughly 60% over the rear. Other decisions were already made—swingarm pivot height (for anti-squat), rear travel at 125 mm, sag at 30%, and minimum ground clearance of 25 mm at full compression.
The AI processed all of this quickly and flagged a few potential issues with the layout. For example, it questioned seat height and clearance above the top shock mount, since it assumed a typical trike layout. Once I explained that I sit in front of the firewall and referenced the Stevenson spec, it adjusted its approach and carried on.
One thing I noticed—it responds better when you’re clear and specific. Good spelling, punctuation, and even a bit of politeness seem to help it produce better results.
It wasn’t a one-shot solution. It took a few sessions to refine everything. Initially, it gives a correct but fairly basic answer unless you guide it with more detailed requirements. For instance, I wanted to maximise a rising spring rate since I’m not using a linkage system. It also strongly recommended adjustable spring preload, as the chosen shock was slightly softer than ideal, and it provided sensible starting settings.
By the end, it produced a full set of workshop-ready specs, including x-y coordinates for mounting points (with the swingarm pivot as 0,0). The free version can even generate a basic dimensioned sketch, while paid versions go further with CNC or 3D printing files.
Overall, I was very impressed with how useful it was.
P.S. The world’s changing quickly—tools like this are becoming incredibly capable.