Stealth electric bikes has a new website, which can be found here, and they have also made some changes to the details of their three models of electric bike.
If you are not yet familiar with Stealth E-bikes, they are the premier providers of high-powered “turn key” electric bikes. They are professionally designed and assembled in Australia, and they have full warranty support from a network of 39 dealers from around the world.
Their flagship Stealth Bomber is now called the B-52, in reference to the 5200W it now provides. It is also a reference to a very powerful and long-serving military aircraft from the US Air Force. It gets the 5200W number from 72V X 72A.
The F-37 number comes from its max power of 3700W, which is the result of 48V X 77A, and all of these Stealth models currently use a very safe, long-life-cycle, and reliable LiFePO4 chemistry that is well known.
Owners have reported that the motor apears to be the well-regarded Crystalyte 4065.
The Hurricane model is not as well-known, but I can only guess that happy customers have been requesting the features that the other two models didn’t have. This model is a light off-road E-motorcycle, since it not only has a motorcycle-style seat, but it has the higher power level of the Bomber, coupled with some lighter and less-expensive pegs, instead of pedals.
The rear suspension provides 250mm (10-inches) of rear wheel travel for impressive off-road capabilities.
Accessories and Options
The current stock colour options are Black Ace, Snow White, Devil Red, or Camo Grey. However, Stealth is more than happy to accommodate any custom colour you may be interested in.
One of the most popular accessories to add to a Stealth is a headlight, to allow for more riding time when the sun is going down. The factory developed a rugged unit to integrate into the Stealth system, and it is available for all models. The picture is courtesy of Quigley Motorsport in beautiful Adelaide, Southern Australia.
All Stealth bikes come standard with the Duro Razorback knobby tyres for the dirt, or Crazy Bobs for the street. The Razorbacks are an aggressive off-road tyre, however their soft compound tends to wear quickly on hard roads or concrete surfaces, and the flexible knobs sometimes affect cornering on hard surfaces . For those who plan on predominantly riding paved roads, the Crazy Bobs allow you lay the bike over into corners with excellent traction.
MRP Groove 200 forks
The stock RST R1 forks on Stealth E-bikes are very well-regarded, and have a wide range of compression and rebound damping adjustability. However, some extreme riders want even more suspension travel to soak up extra hard landings from taking big jumps. Stealth now has an upgrade option to use MRP Groove forks from Mountain Racing Products.
An interesting feature of the Groove line is they are “inverted”. The basic design of telescopic suspension forks normally places two smooth tubes inside another two larger diameter tubes, with the springs and oil damping hardware installed inside the lower fork legs.
For decades the smaller tubes (the chrome-plated stanchions) were on top, which meant that if you ride through mud and grit, some sludge could build up on top of the seal that keeps the junk out of the inner workings of the suspension. This grit may scratch the stanchions (which need to remain smooth to allow a proper sliding seal) and might also damage the rubber seals over time.
The trend in off-road motorcycles has been towards inverted “Upside Down” (USD) suspension forks. The main advantage of inverted forks is that they allow for longer travel, and a longitudinally stiffer fork (for a given equivalent weight). Un-sprung mass is also reduced because the outers (larger tubes) are no longer attached to the moving part of the fork, allowing them to be much larger and thus stiffer than a conventional fork leg.
One of the most significant advantages of the MRP Groove 200 forks over the RST R1 forks is that while compression and rebound damping can be adjusted by turning the appropriate dials, further adjustment can be made by using air pressure to improve the progression of damping adjustment.
Notice that only the right hand side has an external reservoir. This reservoir can be charged wtih air or nitrogen gas to increase the rate/ramping of the compression damping as the forks move towards the bottom of its travel stroke. Compression and rebound damping are both handled by the right hand fork leg, while the left hand fork leg contains the coil spring which can be swapped out for more or less spring preload.
The stock RST R1 forks are stout performers, and a great value for the exceptional performance they provide. But if you are cycling them hard enough and often enough that they are getting too hot or bottoming out…you need to step up to the Groove 200’s.
Written by Ron/Spinningmagnets, October 2014