Varg Weights

[FYR]

There's been some discussion about how the Varg seems to be more difficult to loft the front wheel at will. And, in all honesty, I too find this to be a phenomena related to the Varg, regardless of the mapping/power selections. I don't claim to know much more about that than anyone else, but it could be related to the overall weight or weight bias of the bike.

I did find that my Varg (in stock trim) weighs 271.0 lbs. on my digital pod scales. I use these scales to set up my autocross race cars and they should be very accurate when you consider how much I paid for them (lol), but use this info for reference vs. fact, regardless.

Overall Bike Weight: 271.0 lbs. (note: this is with 2.0mm thick butyl tubes because the original tubes didn't last long enough for me to weigh)
Front Wheel/Rear Wheel Split Weights: Front = 134.6 lbs. , Rear = 136.4 lbs.
Front Wheel Assembly (complete, without axle) = 18.4 lbs.
Rear Wheel Assembly (complete, without axle) = 25.2 lbs.

This all said, I see this as a great opportunity to document complete bike and individual component weights of the Varg. So please, if you guys that have had to replace parts, make warranty swaps, etc., please take a moment to throw your parts on a digital scale and send in your numbers. I will keep a spreadsheet going so we can see where/how our bikes compare and give you credit for your info.

Now, one of my other offroad bikes as compared to my Varg - KTM 250SX (not stock, modified for woods racing):

Overall Bike Weight: 228.1 lbs. (note: this is with Tubliss conversion which weighs more than standard tubes)
Front Wheel/Rear Wheel Split Weights: Front = 110.9 lbs. , Rear = 117.2 lbs.
Front Wheel Assembly (complete, without axle) = TBD
Rear Wheel Assembly (complete, without axle) = TBD

If you just look at the front bias weights of the complete chassis that might give you a hint of why our Vargs feel so front heavy. 23.7 lbs. is just a bit less than a 24 pack of bottled microbrew beer. Not to mention that the weight transfer when trying to loft the front wheel actually rotates around the rear axle. Now image trying to loft your front wheel with a case of Sierra Nevada Pale Ale strapped to your front fender.

 

[rayivers]

Here's some Alta-related info, from a post I made back in 2020 - not all will help with the Varg, but some might:

"When I first started riding electric in the summer of 2014, I was a little disappointed at how heavy the front end felt as compared to my ICE dirt bikes. I tried a number of things and kept the ones that worked, ending up with a bike that popped the front up easily under 25mph even when traction was limited. This was a huge improvement, and adequate most of the time.

In early 2018 I made the giant upgrade to Alta and immediately loved the bike, but the front-heavy 'electric feel' was back - so Round 2 of mods began. Below is my 'mod strategy' based on my experiences with the previous bike, brief list of what I did to the MXR, and how well each thing worked relative to the others.

Strategy, in no particular order:

a) modify front/rear weight distribution, static & dynamic
b) reduce anti-squat forces
c) improve RW traction
d) increase RW torque (not really needed with the Alta, but I tried 11/60 sprockets anyway)

Mods I ended up with, from most to least effective:
1) triple clamp offset changed to 18mm
2) handgrips moved rearward (#1 above, rearmost TC bar-clamp position, Pro Taper Raptor bars)
3) 18mm shorter wheelbase (@ 3mm from #1 + 15mm from shorter chain)
4) 12 / 48 sprockets, done at same time as #3
5) Cannon Racecraft 5.8 spring
6) wider rear tires (4), 2.50 rear rim

As with the other bike, effects were cumulative. A 'tipping point' was finally reached where previous small gains suddenly resulted in a noticeably lighter-feeling front wheel in most riding conditions. IMO there's still room for improvement, though."

 

[FYR]

@rayivers Thank you SO much for chiming in! Any info helps and your's certainly was an effort that will be factored in - cheers!

Along the lines of what you had done, I too am trying other things to help offset this. One thing in fact is by moving central bio-mass rearward. I've made up a set of foot pegs that are situated 40mm rearward of the stock location. Initial testing is extremely positive, especially in technical terrain (subjective, of course).

 

[RCard42]

@rayivers Thank you SO much for chiming in! Any info helps and your's certainly was an effort that will be factored in - cheers!

Along the lines of what you had done, I too am trying other things to help offset this. One thing in fact is by moving central bio-mass rearward. I've made up a set of foot pegs that are situated 40mm rearward of the stock location. Initial testing is extremely positive, especially in technical terrain (subjective, of course).

View attachment 13189

Nice pegs - what we know to know about is your shop rag and mop head art. What's happening here?

 

[rayivers]

Yes, I did a similar thing with my Zero's pegs - then I had to get the brake pedal to work right again.

Does your Varg's front end come up easily on pavement? The one I rode (s/n 013, I think) was a terrifying 80hp unicycle, could only give it full throttle at very high speeds & leaning way out over the F fender.

 

[FYR]

Nice pegs - what we know to know about is your shop rag and mop head art. What's happening here?

My wife's an old hippy and I've got that kinda shit all over the house. Makes for decent (soft, warm) knee protection from the concrete.

Sorry about that, it's gotten to the point where I don't even see it anymore.

 

[DirtSurfer]

Personally, I'll be really interested in how adjustable the power curves will be w/ the EX, as I have zero interest in 80hp, but I have a TON of interest in a 2T like power band (in enduro, which is where I plan to spend the bulk of my time on this bike).

Watching Eddie do his thing makes me believe the power curve is out there, he's constantly doing small wheelies over obstacles.

 

[Beagle]

Watching Eddie do his thing makes me believe the power curve is out there, he's constantly doing small wheelies over obstacles.

They've been experimenting on this with official riders for sure. But Eddie doing Eddie things doesn't really imply he's using extra gadget, it's just Eddie.

Like looking at this vid you'd think the tame 24 hp CRF250L has a hidden extra boost function somewhere.

That being said, I do believe they're finally coming up with adjustable power curves, we'd know for sure in about a month with first deliveries.

 

[Theo]

There's been some discussion about how the Varg seems to be more difficult to loft the front wheel at will. And, in all honesty, I too find this to be a phenomena related to the Varg, regardless of the mapping/power selections. I don't claim to know much more about that than anyone else, but it could be related to the overall weight or weight bias of the bike.

I did find that my Varg (in stock trim) weighs 271.0 lbs. on my digital pod scales. I use these scales to set up my autocross race cars and they should be very accurate when you consider how much I paid for them (lol), but use this info for reference vs. fact, regardless.

Overall Bike Weight: 271.0 lbs. (note: this is with 2.0mm thick butyl tubes because the original tubes didn't last long enough for me to weigh)
Front Wheel/Rear Wheel Split Weights: Front = 134.6 lbs. , Rear = 136.4 lbs.
Front Wheel Assembly (complete, without axle) = 18.4 lbs.
Rear Wheel Assembly (complete, without axle) = 25.2 lbs.

This all said, I see this as a great opportunity to document complete bike and individual component weights of the Varg. So please, if you guys that have had to replace parts, make warranty swaps, etc., please take a moment to throw your parts on a digital scale and send in your numbers. I will keep a spreadsheet going so we can see where/how our bikes compare and give you credit for your info.

Now, one of my other offroad bikes as compared to my Varg - KTM 250SX (not stock, modified for woods racing):

Overall Bike Weight: 228.1 lbs. (note: this is with Tubliss conversion which weighs more than standard tubes)
Front Wheel/Rear Wheel Split Weights: Front = 110.9 lbs. , Rear = 117.2 lbs.
Front Wheel Assembly (complete, without axle) = TBD
Rear Wheel Assembly (complete, without axle) = TBD

If you just look at the front bias weights of the complete chassis that might give you a hint of why our Vargs feel so front heavy. 23.7 lbs. is just a bit less than a 24 pack of bottled microbrew beer. Not to mention that the weight transfer when trying to loft the front wheel actually rotates around the rear axle. Now image trying to loft your front wheel with a case of Sierra Nevada Pale Ale strapped to your front fender.

The tendency of a motorcycle to wheelie depends on both the horizontal and vertical position of the overall center of gravity of rider + bike. The minumum tractive force to be applied to a motorcycle in order for it to wheelie is, according to a book i own: weight of rider and bike together • horizontal distance between the rear wheel center and the center of gravity / height of the center of gravity. This is done assuming that there is no friction limit and that the bike and the rider are rigid and don't try to utilize the rebound of the fork to lift the front end.
For the Stark Varg, they state 938 Nm of torque to the rear wheel in case of the MX and 1,036 Nm for the EX. Considering that, typically, permanent magnet AC motors of EVs like the one in the Varg produce constant torque from still to roughly half the top speed, you can consider that you can constantly rely on those torque values to wheelie in slow speed situations. The tractive force is torque to the rear wheel / wheel radius. Therefore, for the MX, considering a wheel radius of .34 m, the tractive force with that torque is 2,800 N and for the EX, which has a similar radius with smaller rim and taller tyre, it's 3,000 N!
The height of the center of gravity affects the load transfer to the rear wheel even if the tractive force transmitted to the ground is not enough to wheelie and therefore the friction of the rear wheel will be affected by the height, too.
The only way that occurs to me to raise the center of gravity and get both more grip to the rear wheel and a ahigher tendency to wheelie is to stand up and not sitting.

Or you can ask these guys, they surely know better how to do it:

(Note: the rest of my post with forumlae etc. is serious).

 

[FYR]

So... there's a riding technique that I use, and have used, for large or elevated obstacles. Back in my observed trials days we called it, the "jab-snap".

Ahead of you, you see the obstacle. Then you, clutch/throttle/wheelie/momentum, the front wheel into the obstacle which compresses both front and rear suspensions. The bike unloads, the front wheel clears the obstacle and then the elevated rear tire contacts the obstacle at a point where traction (clutch/throttle/momentum) then drives the entire bike and rider over it. Pretty slick and very fun to do. Practice it, and you will impress your friends

Problem for me is, I can time this perfectly on my two ICE/clutch bikes (or even on my grandson's KTM 85SX) , but still cannot master it on the Varg. I wind up sticking my front wheel too low (which induces sudden stop) and going over the bars... which does NOT impress my friends, it amuses them. Someday (hopefully soon), I will manage to capture a tiny bit of the magic that Eddie Karlsson apparently has, and succeed at an electric "jab-snap".

Video attached refers what we old New Englanders called a "jab-snap", as the "Zap technique". Same shit, different nomenclature.

 

[rayivers]

So... there's a riding technique that I use, and have used, for large or elevated obstacles. Back in my observed trials days we called it, the "jab-snap".

Ahead of you, you see the obstacle. Then you, clutch/throttle/wheelie/momentum, the front wheel into the obstacle which compresses both front and rear suspensions. The bike unloads, the front wheel clears the obstacle and then the elevated rear tire contacts the obstacle at a point where traction (clutch/throttle/momentum) then drives the entire bike and rider over it.

+1. I'd add that at the rear there's a battle between the anti-squat effect extending the rear suspension and rear weight transfer compressing it. I noticed some fairly small rear sprockets on the bikes in the video, could be they're looking for less anti-squat at the expense of RW torque. Obviously, F & R damping rates should allow big/quick compressions and rapid return rates for maximum 'kick' from the moving masses.

Given the nearly 50/50 weight distribution of your Varg, I'd suggest keeping on doing what you're doing - moving as much weight to the rear as possible, and making sure the rear suspension allows super-quick compression for max weight transfer under acceleration. I'd do your initial weight-transfer-mods testing on pavement, to minimize the wheelspin variable