Fat tire bike mid-drive Conversions

My Surly My Other Brother Darryl wheels also have Salsa hubs. They are the stockers that came with the BFD. If you have 29er MYOBD rims, do yourself a big, fat favr and do NOT try and remove the tires from the wheels. My own MYOBD wheels are so difficult to remove tires on, for the first time in my life I took them to the LBS to switch tires for me. The mechanic there told me they were the most difficult rims he had ever worked on. FYI they lack the depressed center channel most rims have to make tire removal... possible. It is 100% of the reason I built up a second set of wheels for the BFD... I knew roadside repair was impossible with the MYOBDs and I can't have that.

Good move on staying away from 12s on a mid drive bike. Its a bridge too far. 11s is fine with the right equipment (Sunrace CSMS7 pinned steel cluster) but 10s is a newer (cheap) option via the Microshift Advent X derailleur, shifter and 11-46T steel pinned cluster. Its what I use on my Bullitt hill climber and it takes brutal punishment, trouble-free.
They are Surly Rabbit Hole rims, they say they are a mostly single wall rim but there are spacers close to the sidewalls, they are calling it a hybrid single/double wall. 50mm wide with cutouts. Being single wall in the middle it doesn't look like it will be unusually hard to get the tire off. They said it was to be paired with their 29 x 3.0 tire called the Knard.
Unfortunate outcome. Hopefully you will get your money back out of it, without it being on the market too long.
I think I will be able to especially if I clean up the 29" wheels and sell them separately.

The bike looks newer than it is because it is in really good shape, the paints almost perfect and the tires look new. For someone wanting a fatty snow bike this would be great for a lot of people. There's a fat tire bike race/event in Silverton in February https://silvertonwhiteout.com If I don't get it sold before that I might bring it over and put a for sale sign on it. I have been wanting to go over and check it out someday anyway
I was figuring out what I will need to build the Growler fat bike and reading an article on difficult installation that was linked on Luna Cycle https://electricbike-blog.com/2015/...xes-for-non-standard-bb-intrusive-chainstays/

In the article there was a link to California Ebike for motor spacers. Where I found this, https://california-ebike.com/produc...ll-fat-bike-modification-kit-for-bafang-bbs02 a long shaft kit to convert a BBSO2 to fit 120mm bottom brackets. I have an extra BBSO2 motor with the standard 68-72mm axle shaft and a Leiki Bling ring 40t, so I am thinking of doing this. I think it might be an easier fit than the BBSHD since it's smaller and also a couple of pounds lighter. I really like the BBSO2 I've heard it's not as durable as the BBSHD but I like it's smaller size and lighter weight and it's plenty powerful enough for my wife, she's 110lbs. Also this bike is built really light and I would like to keep the weight down as much as possible.

I asked California Ebike when they expect to have the BBSO2 long axle kit back in stock. If it is going to be a while I'll probably go ahead and get a BBSHD motor and get it built, get this kit as well and then when I find a suitable fatty to build for myself I'll switch the BBSO2 onto the Growler and use the BBSHD on my bike.

I'm going to need some spacers either way, they have Leiki spacers at California Ebike (out of stock) and individual spacers at Luna also out of stock. If I can't find any I will buy a piece of aluminum tubing and cut/make them myself. https://store.buymetal.com/aluminum/round-tube/aluminum-round-tube-6061-t6511-1-625-0-125.html I'll do some more looking around first. If anybody knows of any BB spacers that are available right now please let me know.
It looks like the BBSO2 with the 120mm long axle kit from California Ebikes is going to be a good fit for the Growler I don't have the long axle kit yet, California Ebikes is slow getting it shipped out. I just slid the motor into the bb shell with 10mm of spacers and it has 2mm of clearance between the chain stay and the 40t Leiki chain ring teeth so with 10mm of spacers on each side it will be centered.

The threaded lug on the motor where the bb support connects hits the down tub right in the center so it can't be brought up as close as it would otherwise fit. The motor only hangs down a bit more than the 40t chainring so it looks good to me.

The chain line looks perfect, as good as the bikes original chain line possibly a tiny bit closer in.


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I am getting ready to build a couple of fat tire e-bikes for me and my wife and found a couple of bikes that look suitable on craigslist. A good deal on a 26" Surly Ice Cream Truck. It looks like a great bike for a mid drive conversion and would be a good size for me.

And a Growler Performance Bikes for my wife, it looks like it would fit her well and comes with 27.5 wheels and narrower tires and the option for 26" wheels with fat winter tires.

They both look like good candidates for a build but I just wanted to get get some other opinions. I haven't ever heard of a Growler but it looks like a nice bike, aluminum frame and magura four piston brakes. Also it looks like it has good chainring clearance. The Surly Ice Cream Truck is a steel frame and it doesn't look as good for chainring clearance.

I was hoping that maybe m@robertson would chime in, I was thinking he has an Ice Cream Truck, but then I remembered it's a Big Fat Dummy that he has. Anyway I'm planning to use BBSHD kits with either a Luna cycle or Leki small front chainring. I'm going to go look at them and maybe buy them on Tuesday. I haven't ever done a fat bike conversion so any helpful advice would be appreciated.
I purchased a Growler quite a few years ago. It's a well made Fat tire bike and has given me a great time traveling on her with no problems whatsoever.
The fine folks at Growler bikes which is based in New York are top notch.
You won't go wrong with a Growler!
I purchased a Growler quite a few years ago. It's a well made Fat tire bike and has given me a great time traveling on her with no problems whatsoever.
The fine folks at Growler bikes which is based in New York are top notch.
You won't go wrong with a Growler!
Yeah it worked out really well, the Ice cream truck not so much. I am really impressed with the quality of everything on the Growler It's a really sweet ride!


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