JARV-E (enduro)

[Beagle]

Legendary enduro rider Graham Jarvis is putting his name to a project of electric Enduro bike.



Lighter than a Varg, hot swappable batteries (although obviously smaller), app controlled from your own phone is what a lot of Enduro riders have been asking for, so it could be interesting.

The bike is light but so are the details about this project, with a production start scheduled in about 4 months...

50 kW (68 hp)
95 kg
5.6 kWh

That makes it an intriguing prospect if it's specced more like a Varg than a Surron to handle rough terrain, and if the price is right (no information about that).

Sirris suspensions, like the Dust, e clutch, and likely made in Austria

JARV-E | Electric Hard-Enduro

Revolutionary electric hard-enduro bike co-developed with legend Graham Jarvis. Up to 5 hours of riding time on a full charge, 20-second battery swap, 45° climb capability. Fully built in Austria.

jarv-e.webflow.io

Founder has been developing e-bikes for a while and finished Romaniacs emoto expert category last year on supposedly one of his prototypes

Profile

www.redbullromaniacs.com

 

[Theo]

Some additional information from the website, some of which is got hovering the mouse cursor on the + signs on the picture:
• Sirris F43 suspension; interestingly, it seems to be a dual chamber fork with Ø43 mm stenchions but the F43 writing pops up hovering the cursor over the rear shock
• rear shock without linkages and a visible tilt that I presume achieves progression instead
• 21"-18" wheels
• e-clutch
• CNC milled swingarm and triple clamps; in other topics we got to the conclusion that those propotypes have machined triple clamps probably because casting would be more expensive for small batches, but apparently this is marketed as a permanent feature
• 3.4 kW charging
• Jarvis is not only going to sign the bikes, he is part of their team: "He leads riding development, testing, race strategy and the long-term vision for JARV-E." He has also developed a riding mode available for the customers.
• The battery capacity after 500 charging cycles is expected to be 80%.
• two years warranty

I like that the prototype is being raced in important competitions before they even produce the bikes. Racing is the real test people want to see.

They are also hiring to expand the company.

 

[Beagle]

Good eye!

I like that they already foresee to make replacement packs available.

The path from prototype to production is hard, they appear to be at very early stage without any release date nor price.

 

[Kurlon]

So, not a motocrosser with that frame design, I do like some of their setup choices though: Chain primary rather than enclosed gears, simpler, lighter though slightly more power loss. Main shaft is also the swingarm pivot so constant chain slack at all times. IIRC this impacts anti-squat though, not sure it's really a concern at hard enduro pace vs say, road racing where I normally play? Front sprocket changes are going to require major disassembly. Looking at long term strength, that steering stem area is spindly, and the swingarm pivot is behind the main rear downtube with not much visible bracing / triangulation? Again, not a MX/SX targeted machine.

EDIT: Looking closer at the swingarm pivot area, I just realized, the pivot point is adjustable. The silver side plates that also hold the pegs are the entire pivot point structure, it's not supported by the frame at all. The forward mount point for those plates has two holes, by changing which one you use you can move the swingarm pivot point up or down. This alters the shock progressiveness and swingarm angle. It also moves the pegs relative to the seat/frame a bit too so, interesting... The mount bolts for those plates are blocked by the primary sprocket so can't go all the way across for strength on the rear bolt, front bolt looks to possibly be able to be a single bolt across the frame with a gusset tube between for strength?

SIRRIS suspension scores again, the rear geometry worries me though... I'm used to PDS / linkless setups, this is setup to be VERY progressive, and eyeball math has me worried that a hard hit could push it 'over center' depending on how hard the stop is on that shock? I'd like to get the actual numbers on it to run the math.

That said, I do like finally seeing a full size machine that appears to actually benefit from going on an electric diet. This has my attention as likely a closer match to my actual ability set these days, and much lighter, this is closer to my two strokes that I love weight wise. I do hope they come out with alternate rear side plates with more number plate area AND mud flap function.

 

[Theo]

Main shaft is also the swingarm pivot so constant chain slack at all times. IIRC this impacts anti-squat though, not sure it's really a concern at hard enduro pace vs say, road racing where I normally play? Front sprocket changes are going to require major disassembly.

I haven't found pictures of the bike from the right side, but yes, from the left it looks like that. Some BMW designed Husqvarnas like the TE 449 used this solution, that they called CTS: Coaxial Traction System. Here is an interview about it to an Italian professor from back then; the subtitles seem right except for when he mentions landign from a jump doing cross country: it's motocross, not XC:

The advantage of less slack in the chain + the instantaneous torque of the electric powertrain must make that one of the most reactive motorcycles ever made.

SIRRIS suspension scores again

Well, I've found out that for that fork, for example, there are spare parts available like this rebuild kit and tutorials like this about how to change the spring. I don't expect to find as much spare parts and information as with older, more common manufacturers, but I also guess that they would be cooperative if asked technical questions.

the rear geometry worries me though... I'm used to PDS / linkless setups, this is setup to be VERY progressive, and eyeball math has me worried that a hard hit could push it 'over center' depending on how hard the stop is on that shock? I'd like to get the actual numbers on it to run the math.

When you say "over center", do you mean like this? It doesn't look like it can compress so much.

 

[Kurlon]

That's exactly what I meant, either going digressive or absolute worst case scenario, the shock starts forcing the swingarm UP. Ran into that with some Chinese pitbikes back in the day, they relied on a rubber soft stop to keep things in check. Hammer a jump as an adult on said bike and suddenly your swingarm was stuck beyond fully compressed. (And if you had adjusted the chain as per the stickers, likely either snapped the chain or bent the output shaft...) I have to assume they're aware of and designed to not allow that to happen, but it was my first thought looking at the layout.