Yeah, absolutely trying to minimise the time to prep each part. Both in the physical effort and the time it takes. I want to ride bikes, not just make them. Haha
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also to add, I am getting things like the BB threads and the main pivot machined in the bottom section of my frames. I could set up and do them both myself but the reasonable charge they ask is less than the time/cost it takes me to do and it’s bang on accurate. Plus the responsibility is on them to do the work. If I stuff it up I’m down a part and potential it’s a stop work. Once they send it out, it should be good to go. That is the only caveat, that their QA/QC is adequate. The last order I had came with two left rockers when I definitely sent left and right models. I ended up modifying those models anyway and getting them reprinted, which means their error is inconsequential at the end of the day.
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To finish up the v2 story, here’s my analysis of the kinematics and comparison to v1.
I must say that if you haven’t made a full suspension bike with a gearbox and 24T chainring, the space is very limited and finding the optimal points is almost impossible. So if you think the kinematics are funky, I welcome you to try for yourself 
Overall, the v1 kinematics were fine, and I didn’t intend for the v2 to be that different. For the dual-link suspension, it just came out like this after the million iterations…
Also, I dropped the BB height on the v2 by 5mm, which leads to inevitable differences.
Leverage ratio: Yes, it’s pretty progressive, which by itself is OK. But yes, there is a “wall of support” somewhere after the mid-support area. What I thought that the high start ratio would do is be very supple in near the top-out (for example on a rooty trail where the rear tire is in the air occasionally), but that was surprisingly not that different. What I found was that how much the damping is affected also. So, when pedaling, the rebound is a bit wallowy, which could use more low-speed rebound. But on deeper hits you have too slow recover. So you are stuck with adjustment that is ok in the middle and sucks a bit on both ends. Of course with valving this could be made better, but I haven’t got into that.
For v3: Dial back for more linear curve.
Axle path: Pretty much the same. This is not a driving factor after all, but rather the outcome of anti-squat and leverage ratio etc.
Pedal kickback: When I rode the v1 in chunky bikepark stuff, I was certain that most of the pedal-kickback that is usually felt at feet, is actually the derailleur and chain flapping around and yanking the chainring. I mean on paper it seems high, but it is pretty much non-existent on the trail. So, I was not concerned at all about it being even higher on v2. Which was not the case, because it seems that on v2, I found the threshold where the kickback starts to happen with “normal” enduro-riding. Still, I can’t say that I felt it on the feet that much, but definitely can hear the DT Swiss ratchet “clunk” when dropping to some rough stuff. Then again, I haven’t ridden these bikes chainless, so…
For v3: Dial back closer to v1 level.
Anti-rise: Maybe my lack of riding skills, or the lack of mountains in Finland, but I haven’t noticed the effect of Anti-rise that much on any of my bikes. From what I now understand, it is better to have it high (~100%) if you are pro AND ride steep DH-trails. Then you are not pitched forwards during heavy and brief braking. For mellower trails, and riders who drag the rear brake, it is better to have lower Anti-rise (~50…80%), for better bump absorption during braking, because the rear suspension is riding higher, therefore the spring rate is lower. Again, this is not the most important factor for me, and if you think that the curve goes way up deeper in the travel, keep in mind that the force generated by Anti-rise is also dependant on the actual braking force. So, you would have to bottom-out AND brake hard at the same time, which in my view calls for trouble with any anti-rise curve. Of course, a flatter curve would be nicer. I think the jury is still out whether the curve should be rising, falling or flat.
Anti-squat: On the v1, Anti-squat seemed high enough, with very little bobbing. On the v2, I don’t feel that much difference, I have learned to “rotate” the cranks more (with some ankle movement), rather than stomping with big muscles alone. I think the optimal Anti-squat is somewhere 100…120% in sag area, with a falling rate, because the spring is going to do half the job anyway deeper in the travel. So the falling rate helps to keep pedal-kickback lower deeper in the stroke. What I did notice on v2, that I lost some of the amazing ability of the v1, when pedaling on a flat trail with lots of roots. On the v1, it just floated through, and the v2 slows down more and the rear tire bounces in the air more easily.
For v3: Again, dial back closer to v1.
Forces: What I like to do in Linkage when comparing different designs and iterations, is to have the model setup with coil-spring and match the spring rates, so the sag is the same (49,5mm for 165mm @30% sag). So here we can see that v2 has much easier rate in between the top-out and sag, and the mid-support is quite massive, with an even more progressive bottom-out for that bottomless feel. The actual outcome I already told in the Leverage ratio pic… 
After all, the v2 is not that funky that it may seem from the pictures. It’s still prefectly capable and predictable, which tells me that you would have to be way off in the kinematics for a bike to be unrideable. Of course, the industry has solved these pretty much in the past 20 years or so, so for a guy like me, it is easy to land on some acceptable design. And the bike is still the combination of kinematics, geo, stiffness, weight and components.
Please, feel free to discuss, what do you think are the optimal kinematics? Am I way off in my theories and how I feel them on the trail?
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Last winter, I did my first paying gig as Nikomi Bikes (don’t worry I’m not giving up my day job 
). A friend has a business in trail building, and he also does maintaining during winter. A good solution (one of many) for grooming winter trails has been pulling a car tire with a fat bike. E-fatbikes are great for this because, of course, it takes quite the effort to pull anything behind the bike, also the power output is very smooth on ebike, and also the mass does not hurt here. So to maximize the effort and capability of the bike, this friend came up with the idea of having the Surly 24 x 6.2 rear tire fitted to this Tunturi full-suspension e-fat. This way the bike itself is not modified, I would just make a hardtail conversion kit for it. The Tunturi could always be restored to original form by swapping the original parts.
As usual to me on everything I make nowadays, I designed the thing in Solidworks, to work out all the details including the chainline and offset needed for the rear hub.
The rear hub ended having 10mm offset, on top of the UDH dropout. For the chainring I turned some spacers to widen the chainline 8mm.
Chainstay length is 495mm.
The customer worked out the cassette, which he reduced to 9-speed (you don’t need that many on ebike do you?). On the test ride I did, there was some chainrub on the smallest gear though.
It came out a bit flexy still, but it works!
Are there other bikes in the world with this tire and a “normal” drivetrain? How about ebike?
I don’t know.
Enjoy!
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This is so rad! Nice work
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The angles are pretty wild, notice the “raised and reversed” cockpit 
