Want to build a Full Suspension Mid-Fat BBSHD MB and need to find the right bike/fit.

[toddphillips]

Questions:
How good of a suspension do I really need if I’m really looking for comfort with longevity on steep mountain single-track?
Will slightly fatter tires (2.8 to 4inch) really make that much of a softer feel, and is it worth the hassle of the possible chain line/bottom bracket issues?
Why does it seem like there aren’t many fat tire full suspension bikes?
What bike would you have me look at?

I plan to use the bike for mountain biking in the Santa Cruz Mountains, and I need the full suspension not because I’m a radical biker but because I have injuries and want the comfort and support of a suspension. I also want to sit a little bit more upright, and have long legs and a short torso, so getting the right fit and comfort on a bike is super important and the main point of this post!

I’ve had a couple of snafus in my process so far. Bought a new hard tail (Giant Fathom 29-2), bought a BBS02 kit, found they weren’t compatible, and then installed the BBS02 on my 24-year-old Giant ATX 770 MB. Now I have basically an electric bike that’s good for town riding, but it’s too stiff to ride much on trails, even with a thudbuster suspension seat.

I could get a BBSHD and put it on my new hard tail, but I don’t think that would satisfy me so now I’m looking for a 3^rd bike to convert. I’ve considered buying Luna’s assembled Fusion Crusher, but it does not come in XL and I don’t think the L will fit me, plus I would love to get tires a bit bigger than 2.25, maybe 3 inch for the extra cush. For some reason I’m not finding much in the way of mid-fat FS bikes. Is there a reason for that?

Also since I’ve never had an FS bike, it’s very difficult for me to evaluate them. Basically I’ve been looking for rock shocks or Fox with 140mm plus travel, but really I’m just guessing what will work for me.

I rented this bike (now on sale).

https://currentebikes.com/product/haibike-sduro-allmtn-6-0-2017/

I liked the feel of the fit of the bike, the 2.8 tires, and Torque sensing sure makes the bike feel integrated, but I really missed the lack of control around power that I get with my BBS02 and a throttle.

I’m looking as less expensive or even used bikes, but as I had difficulties with the build I did I don’t want to end up in another mess. Some of the bikes I’m looking at:

http://www.bikesdirect.com/products/motobecane/full-suspension-mountain-bikes/hal5-nx-275-mountain-bikes.htm

or this one with 2.8 tires

http://www.bikesdirect.com/products/motobecane/full-suspension-mountain-bikes/hal-boost-elitegx-275-mountain-bikes.htm

or similar Giants for even more money.
But with all of the Motobecane I have no idea if the battery will fit! Sigh….

Once again the questions again are:
How good of a suspension do I really need if I’m really looking for comfort with longevity on steep mountain single-track?
Will slightly fatter tires (2.8 to 4inch) really make that much of a softer feel, and is it worth the hassle of the possible chain line/bottom bracket issues?
Why does it seem like there aren’t many mid/fat tire full suspension bikes?
What bike would you have me look at?
Any other advice you have for me?

Thank you!
Todd.

more about my saga so far...

https://electricbike.com/forum/forum/knowledge-base/motors-and-kits/bbshd/44980-just-finished-my-first-build-chain-line-pedal-assist-and-setup-questions

[Harold]

The fatter the tire the lower tire pressure you can use which will make it cushier. Also handles the terrain better. The mid-fats go up to 3.2 wide and the fats start at 3.5 -5.
The shock travel depends on how rough the terrain is and are you going off of jumps. The 2.4" tires will go down to 30 psi, 2.8-3.2 tires 20 - psi, and fat bike tires down to 6 psi.

With my last build, I started with a f/s fat bike frame which will handle a 4.3" wide tire. Went with a 120mm travel 27.5+ boost fork which will handle up to a 4.0 front tire. I'm using 26" x 50mm rims which lets me run anything from a 2.4" - 4.3" tire. In the summer I use 26" x 3.0 front and 2.8 rear. When it starts getting muddy and snows I'll switch to 3.8 Nates. If I want to go to a fatter front tire I can swap in a fat bike fork.
To me, the most versatile set up would be a f/s fat bike frame with the 27.5+ fork. Make sure the rear shock has a lockout.
Depending on how much pedaling you like to do will dictate the battery size. I use the mighty mini and find that's more than enough for the way I ride.
On my f/s fat bike I use a 42t front ring with a 11-36 9 speed cassette. My wife's bike is set up with a 36T front ring and 11-36 9 speed cassette. On my last build (not ebike) I have a 30t front and 11-40 10 speed cassette, which would let climb pretty much anything.
I prefer to find a frame I like and build it vs buying a finished bike. Not really cheaper, but I get the components I want. There are a lot of frame choices, just gets down to your budget.

[toddphillips]

Thanks Harold! You seem to really like those fatties. I borrowed a friends Sondors ebike for a while and loved it for cruising around in the flats or the beach, but really I see almost all 1.8 to 2.2 tires on mountainbikers here and I wonder why that is. I think part of it is Santa Cruz Bikes is right here on the edge of town by the state park, and they rent their $8000 demos for $20 bucks for a day!!! A lot of people are riding those.

Truthfully I don't want to get too into doing a super custom build. Like I said, I'm not a big radical mountain biker. I just want to find a comfortable way to get out in nature, get some exercise, have some fun, and not injure myself further. Doesn't it get much more expensive buying bikes piece by piece? My idea would be to buy a complete FS mid-fat bike, buy a BBSHD, install it myself with the 42 lekkie like I have on my ATX770, and use the 52V shark pack I have if it will fit, and call it a day!

Thanks for the tip about rear suspension lockout.

[toddphillips]

Also I'm wondering about how you find the geometry of a fatty differs from an all mountain bike? Fatties seem a bit more like a cruiser to me, and I do want to sit a bit more upright. But if that's true, how is it for lots of climbing up and down hills and single track?

[Rodney64]

You do need good suspension if you want a comfortable ride. I would look at a good second hand Specialized Enduro Expert 2008 to 2010, the travel on these bike is 180mm. I have one and the riding positions good and the large frame fits a standard shark pack.

[toddphillips]

Ok, I'll look to see if I can find one of those. So how do I know if a suspension is good? I've never had an FS bike so all I know to look at is brand name and travel mm. I've been thinking Rock Shox or Fox at 150mm, but I see so many bikes with less than 150mm. Plus I see these videos with people making fun of bad suspensions, and I don't want to end up with one of those. But who knows, maybe for my uses I might be perfectly happy with a $500 used bike like thisYeti

https://sfbay.craigslist.org/scz/bik/d/yeti-asx-downhill-mountain/6389254635.html

or maybe I need this 2k bike with 2.8 tires but with less suspension

http://www.bikesdirect.com/products/motobecane/full-suspension-mountain-bikes/hal-boost-elitegx-275-mountain-bikes.htm

or this guys "hunting bike" which I have no idea how to evaluate the suspension

https://sfbay.craigslist.org/eby/bik/d/eranger-mid-drive-electric/6377478468.html

Or the Giant Anthem 2 from Luna for 4k. I'm trying to figure all that out, but the bikes aren't all lined up for me to try and compare, and many are far away as to be untestable. Thanks for your help!

[Zippy]

Being in Santa Cruz area I'd suspect you would be able to find a good used FS bike for a decent deal that would work for your purpose, right about 2012 is when a lot of the companies went to the newer style bottom bracket that is a no-go with the Bafang motors if I'm correct there, you'd just have to keep in mind the frame space for fitting a battery.

A good FS bike with 26" wheels and the fattest tires you could put on it would be a pretty good ride(I have one, with BBSHD, it rides awesome off road). FS Bikes built with plus sized tires in mind are readily available but boost spacing is the norm now and they are not compatible with the Bafang motors. If you wanted an actual fat bike with suspension forks on it, well you're going to be paying quite a bit for that too. Might be worth considering setting up a good 26er, just food for thought for you.

[toddphillips]

Ok, there's good information for me in there. As far as the newer bottom brackets, the Bafang BBS02 fits the older style 68-73 mm. If I bought a bike with that sized bottom bracket I could take the BBS02 off my ATX770, install it on that bike, and be done! The Bafang BBSHD though, which is newer, more powerful, and generally better will fit with the newer type bottom brackets, so I have been imagining that I would buy a BBSHD motor to go along with a bike.

Frame spacing for the battery is my big concern, because I ran into that problem with my ATX770, and is one of the main reasons I'm flailing in my search. I keep looking at used bikes and looking at the builds that are listed on the Lunacycle site and not finding matches.

[Zippy]

This blog on bottom brackets standards and fitting the motors is informative, there is also one written by Luna folks that's good too although I don't have the link for that: https://www.empoweredcycles.com/blog...d-drive-motors

[Bizman]

Todd,
I see you want a more upright riding position. A suggestion would be to check out Jonesbikes.com and at the minimum check out the Jones H Loop bar. I bought the 29er + bike with this bar, added the Xtracycle LEAP extension converting it to a cargo bike. I then added the BBSHD with 42t Luna Eclipse front chain ring and 11-42 rear cassette. This bike has 29er + 3" tires so I am unable to get the lowest cassette gear due to the rear chain line/3" tire issue (a smaller tire would solve this or better yet IGH!), BUT, it pedals like a regular bike and it has a motor if I need it, hence having that lowest gear is not much of a problem! This bike is my most comfortable 2 wheeled bike! I tried to find Jeffs video on how he designed this bike and bars and post the link but I could not find it (perhaps ask them how to find it on the website)?. That video is what sold me on this bike and bars, I highly recommend both bike & bars/ just bike/or just bars. You could use the bars on most bikes (I believe)! You could also at adapt any gearing you would like.

I realize this does not have suspension but if you check out his website and videos he uses a "truss" front fork and with the 3" tires it will give you some squish. I do not ride (nor did I get it for) single track, mostly paved and back dirt roads, it is just a wonderful geometry and the bars are so comfortable, although YRMV. I was never a fan of rails to trails but a friend had a 62nd birthday and wanted to ride that many miles on his birthday, in a nutshell I rode 76 miles that day, NO motor usage at all and I could have went a 100 no problem! I think I never had the right fitting bike for that type of riding until building this one. I have been very happy with the geo and bars on this bike and share my good experience with everyone I know that wants to have a more upright and comfortable riding position, good luck, I wish you the best with your search!

[toddphillips]

Thank you! I took a quick look and that setup looks awesome for dirt roads and trails. I wish I had more access to terrain like that. I will consider it.

[toddphillips]

Here are 3 local bikes for sale. Not mid-fat, but they might work. Do you think I could fit my shark pack on these?
2008 Gaint Trance 3, the guy offered $500. https://sfbay.craigslist.org/scz/bik...383599856.html
2011 Santa Cruz Nickel $700. https://sfbay.craigslist.org/scz/bik...393345920.html
2003 rebuilt Santa Cruz Heckler $1000, and XL! https://sfbay.craigslist.org/scz/bik...362668794.html And it's pretty :^)

[Waterat Pat]

Todd you can't go wrong with a Santa Cruz and they all have standard threaded bottom brackets. The Nickel is 27.5 wheel compatible I believe should you want to go that route. The Heckler has a straight downtube which should allow you to rotate the motor forward for more clearance.

[toddphillips]

That is awesome information! Just what I needed to know! Now I just need to try them for fit and get more clear about how good the suspensions are. I'm a little sad to be possibly giving up the mid-fat option, but I like the simplicity of simply transferring my BBS02 onto one of these.

[Harold]

I like the fat frames for their versatility. If the fattest tire your going to use is a 3.2 the mid fats would offer the same advantage. I rode on Skyline in San Mateo for 10 yrs on my Intense with 2.1 tires which worked fine in the dry. I now have the Intense set up with 50mm rims and 2.3 tires which actually measure close to 2.6" which would work better on those trails.
I built 2 f/s bikes this year by buying the new frames on ebay then piecing them together. The price came out the same as buying the complete bike.
My wife has a 2005 Santa Cruz Superlight with top components we picked up on ebay for $900, that's still a great bike to ride. I'd convert it to a bbshd and mighty mini battery if she wanted.
As far as a fork I would post on the local mtn bike forum and ask for suggestions based on the local trails and how you ride.

[fatEbike.LA]

Where can you legally ride an ebike on single track in the Santa Cruz mountains? I am not that far away now and I'd like to check them out over the winter when it is cooler weather.

[toddphillips]

I'm no expert, but my understanding that as long at it's a class 1 or class 2 ebike, then it can go where ever other mountain bikes go.

http://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?sectionNum=312.5.&lawCode=VEH

And there are plenty of places in Santa Cruz where there is some singletrack and MB are allowed.

http://mbosc.org/trails-in-santa-cruz/

[fatEbike.LA]

That applies only to bike lanes on streets and paved bike paths. This law does not have any effect on local land access, so far most state parks and all forestry service and national park lands still consider ebikes to be motorized vehicles and ban them. This is a very very touchy issue in the mountain bike community with lots of bicyclists looking for an excuse to ban us forever. All it will take is one episode of illegal riding in front of the wrong people and we are will never get access to single track.

I checked the map and I don't think any of the single track there is legal for ebikes although you may find a fire road that allows dirt bikes.... If there is any doubt, just call or email any local bike shop or MBOSC, they will tell you where it is legal to ride. Please don't ruin it for everyone else who might have hopes of legally riding there someday by thinking that no one will notice the motor.

[toddphillips]

Ok, thanks for your reply. I did a bit of digging after reading your reply and clearly I didn't realize this issue was so touchy, contentious and unclear. I have definitely seen other ebikes on the single track at Wilder Ranch, where I would like to ride. I've also rented ebikes to ride up there. I will definitely check more with the local community and maybe even rethink what kind of bike I'd like to build. Really I think I'd be super happy to have a fattie hard tail and lots of dirt roads to explore. Thanks again. It takes a village!

[toddphillips]

After reading your comments I went by my local ebike store to see what they had to say. They rent and sell the ebikes I've seen on single track here at Wilder Ranch State Park. I was told that we have it pretty good in Santa Cruz. The owner said he has talked to local officials and that type 1 ebikes, which are what they sell, are allowed on all bike trails in Wilder Ranch, UCSC, Pogonip, Henry Cowell State Park, Delaveaga Park, Big Basin, and Nisene Marks, the first three of which have some single track. Basically I was told they are allowed every place on the link I sent you except for Soquel Demonstration State Forest. Of course they are a bike store, so they may be biased. It does make me think twice about what kind of ebike I am going to build. Because of throttles and no 20mph speed limiters a Luna kit would make it a type 3 ebike, which would not be legal in any place I mentioned. Still learning...

[Peter Halt]

You can unhook or remove throttle and easily limit any luna kit to 20 mph from the display settings if you want to be legal on a California trail.

[toddphillips]

Wow! I hadn't thought of that. What about the fact that Luna bikes do not have torque sensing? One aspect that makes type 1 bikes less appealing to me is the fact that with the ones I rented with torque sensing I was sometimes putting in more effort than I was wanting to even in the highest pedal assist mode. Without torque sensing a 750w Bafang would allow much more power when I wanted it.