Bulls Monster E FS - Anyone Have / Rode One?


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3:07 AM
Sep 3, 2020

Okay, truth be told, I already pulled the trigger. It's mostly for my son as he builds fitness for the hills. It should allow him to keep up with me on the hills and allow for us to do bigger / longer days.

I rode a cheap-o e-MTB in Switzerland two days last week. Both days I was fried at the end. I could've done both rides analog, but since I was in a foreign country, on unfamiliar trails with little online info, I got the e-bike as a safety net. Super glad I did. Honestly, it completely change my perspective on e-bikes.

Anyways, has anyone ever tried this bike? It gets favorable reviews against the Full FatSix from Haibike and a fatty was a must as that is the only thing my son will ride. Curious what others think!
Haibike Full FatSix owner here. The Bulls E FS to me, is what Haibike would have done with the Full FatSix had they gone with the Bosch E-drive system instead of the Yamaha. Both bikes are similarly spec'd in shocks, brakes and tire/rims, so I imagine the ride is comparable between the two brands.

Like your son, I too am a convert to the fatbike, starting out with my Fatboy and graduating to the Full FatSix. Since getting the Haibike 2 springs ago, I've not been back on the Fatboy, the Haibike just being so much more fun to get around on.

I get a kick out of Bulls estimates of 134 miles per charge. LOL to that. Sure, if you move between ECO and no power at all, you'll get that 134 miles from the battery. And the rider will have done it feeling every pound of weight in that fatty!

Haibike Full FatSix.jpg
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Yeah I laughed at that too. But should be plenty for my son. I was waffling back and forth between full fatsix and Monster e FS but went with Bull mostly because I found a place with it in stock. It’s hard to tell if Haibike is discontinuing the FFS? Hopefully shipping on the Bull won’t take forever! Want to get him out on it ASAP!
Rough: I believe Haibike is bringing back the FFS to the US later this year. They even upped the ante with the FFS 10.0 over in Europe, equipped now with the Yamaha PW-X drive system and Sram Eagle components. It will be priced accordingly, which means, OUCH!

Electric Bike Review has a nice review of the newer full suspension fat Bulls as well as the EFS from 2 years ago.

Wishing your son good luck with the bike when it comes in. He's gonna love it!
I've ridden a few Bulls Bikes. They're kind of heavy and the geometry is a couple of years behind. So they're hard to throw around on aggressive trails and tough to maneuver on very tight trails.

The new Performance Line CX Bosch motors are very good and much better than the old ones. But they are tough to pedal when the motor is shut off since there is drag and the front chainring is so small.

It's a fatbike and I would only get that if you're gonna ride in the sand or snow. But it is a great use of assist since fat tires are a big burden on normal trails. Motor kinda negates that. But the maneuverability is hard to get back. Plus tires are better if snow is not a requirement.

Congrats on the purchase. Really pay attention to your tire pressures (get in the low teens) to get comfort, traction and less bounce.
Thanks for the info guys. My son is a good size at 6’ probably 185. I am sure he’ll be able to handle it. His main bike will still be analog. I wanted this an option to expand our local options since hills seems to be his biggest nemesis at the moment.

Just got to keep him going and the bug will bite!
Well it came in a few days ago while I was out of town on a work trip. I assembled it last night and went for a quick tour of my local trail. I did 11.6 in eMTB mode. Below are the pics, below that are my thoughts on this new addition:

Bulls Monster E FS.jpg

Assembly was fast, as in I had it full assembled within 30 mins including minor tweaks to shifting. Should've checked the psi in the front and rear shock. They both were pretty low and I bottomed both out this morning. Immediately when I got home checked the pressure on both and had to add quite a bit to each to get them to a setting that any "normal" person would want. Battery charged pretty fast. It was almost topped off when I got it, so I let it charge last night for about 2 hours and it showed 100% full. Need to get used to pedal cadence and timing as I ended up with quite a few pedal strikes on my ride AND pedal strikes are definitely a bit more serious with an e-bike since it is under power and really throws you around if you hit solid. With the extra weight of the bike, it was a little tricky on some of the more technical sections aka steep and loose. That mass gets momentum fast and one time I was a bit out of control and not in a good way. Narrowly avoided going over a pretty nasty drop into a creek by about 3 cms... Climbing in eMTB basically made me about 100% faster. One of the climbs on my ride I call "The Climb that Never Ends" took me just a little over 5 mins. My previous best time was 9 and half mins. 11.6 miles / +2,100' in eMTB and I had 2 cells left. I wasn't making any attempt to conserve juice. If I would've downgraded to Eco on the flats and DHs, I am sure I could probably do two laps of my regular ride on the eMTB for about the same effort but twice the DH. I can't wait to get the Mrs on it as I know she will immediately tell me to buy her one specific for her.

Overall no regrets yet! I just dry brushed the frame down after the ride and lubed the chain. Battery is charging for another sesh later this evening :)
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Brilliant share. Please keep sharing as you ride it more.

eMTB mode of Bosch is their secret weapon. It's one mode where almost never have to change assist modes. That should be the way it is for all systems.

Even though you bought it for your son. You may find a very frequent user for it... you.

I have a good story. A friend borrowed my Pivot Shuttle for his wife. They did a trail that his wife had heard about for years but wasn't quite ready for (the 2000 foot climb). She loved the ride. Then in the afternoon, he took his 14 year old son out to the local park on his kid's first time there (steep). And the next day, before returning, he rallied all morning long on it. Interesting possibilities.