Swingarm bearings was originally planned to use OEM KTM swing arm needle bearings. However, we chose to machine our own greasable bearings with bronze bushings.
For a more compact chain case design, we have chosen to tension the chain from outside. Of course it is better to put a idler sprocket from the inside but then the chain case would become too bulky that the heel didn't got room enough
Have made a first prototype of tensioner out of a slippery plastic. It has a ridge that slides on the rollers of the chain. We will probably at the end go for a Little different design on this slider but we are so eager to get our first test ride
2 mm carbon fiber cover is lightweight but not the least, looks really nice and high tech
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Almost done. Just the ski left to assemble. Tomorrow will be our first test ride of our GEN3!
Finally maiden voyage in the Swedish mountains with Gen3, really fun!
Gen3, has as you may have seen an enclosed load carrying tunnel design which we believe is very positive because we both avoid snow spray and gets a significantly more rigid structure. The pictures show what we experienced in the short time we've test ridden. The bike gets almost no snow on itself which is really good.
The question will surely come regarding weight. Current kit weighs now 44.5 kg (98,1 lbs) with a potential to reduce weight by 1-2 kg (2-4 lbs) by for examle making tunnel roof thinner i.e. 1mm aluminum instead of current 2 mm. Some parts/covers can easily be made out of carbon fiber sheets.
The brake hose on the right side will get a protected and more apropriative fitting. Currently just a simple attachment with temporary plastic straps.
The lever on the handlebars controls the locking of the third shock. It is originally used on mountain bikes in conjunction with the type of damper we use. The locking can be controlled in three steps. You might also recognize these from Skinz Arc. They use the same system to choose between a coupled or uncoupled bogie.
After our first test ride, we've concluded that mountainbike shock will be strong enough for this aplication. It is rated at max 300 psi but we reached sufficiant firmnes at a modest 220 psi. With the correct geometry will likley end up in 150-170 psi for a good suspension performance.
After our first test ride, we had used 40 mm stroke at the normal running of the total stroke of 55 mm.
It may seem good but we had a lot of sag and it got quite firm at a modest stroke. In other words, the suspension wasn't is not quite optimal.
We would have preferred less sag and less progressive travel.
The solution is to move the rear attachment point downward. By this way, we will have more shock compression in the beginning of travel (start pressure) and as compression travel gets reduced, the shocks built in progressivity kicks in.
We feel confident that this will end up to a better use of the shocks entire spring travel.
We will watercut some new damper brackets with several holes so we easily test out the optimal point of attachment.
The brake disk on the drive shaft seems to work out quite good. A compact, simple and light weight design.
One problem with this solution could probably be more exposure and risk to icing on the disc, leading to some degree to delayed breaking action.
