DIY commuter frameset

[bjorsa]

Hello fellow cyclists,

I would like to build my own e-bike but the google up the mountain quickly threw monkey wrenches my way. Sourcing a frame turned out to be a formidable stumble block. My current setup is a very sturdy Lynskey Backroad touring frankenbike with a BBS02. The wide q have messed up my knees badly. Having entered the old age of constant complaining I would also like a comfort upgrade.
These are my oh-so-humble req:

1. Mid drive - almost any brand will do (preferably Yamaha due to reliability, I also like Brose due to top characteristics and low noise). They are all on ebay, should be fine, no? Or do I need to resort to a heavy and noisy Innotrace Ultra G510?
2. Belt drive compatible.
3. Front geometry fitting around 50-80 mm travel forks - I guess somewhere in the neighbourhood of 450 mm axle-to-crown. (A full suspension frame would also be ok and I understand this would mean more travel.)
4. Commuter specs with fender mounts etc.
5. Must be able to handle at least 25 kg on the rack and some in the front without going twitchy and noodly at high speeds.
6. Much prefer an integrated battery.
7. Reasonably long wheelbase (1120+ for sizes fitting a 175 cm tall cyclist) without toe-wheel overlap.

I looked at the Watt Wagons Helios frame but didn't fancy the long front fork length and M620. Who needs 160 mm of swampy front suspension travel on their way to work, all while sporting a hard ass tail? Browsing the usual suspects of chinese manufacturers e.g. Dengfu, Light-carbon etc I found nothing but an endless parade of almost identical MTB frames. The Taiwanese factories I recently spent my late evenings oogling were only interested in selling to OEMs and OBMs; reminded me of my youth, ouch. The European providers of fitting frames, like Messingschlager, only deals with resellers and wouldn't touch my money with a 580 mm downhill fork.

Now that I've framed the problem and steered you into my wheelhouse: what the fork would you have me do? Any advice greatly appreciated!

 

[Dewey]

Gates have a handy brand selector on their website, and since you are in EU here are a few EU models, mostly Bosch except the Flyer which is using a Panasonic motor. The Riese & Muller Delite is a full suspension model.
Flyer GoTour4
Victoria eTrekking 7.8
Trek Allant+ 9S
Kalkhoff Endeavour 7.B Belt
Riese & Muller Delite GT Vario

 

[bjorsa]

Thanks for your reply. However, those are more or less complete bicycles. I seek a frameset. Wheels and stuff I build myself.

 

[Dewey]

Thanks for your reply. However, those are more or less complete bicycles. I seek a frameset. Wheels and stuff I build myself.

OK, usually for custom frame builders I browse the lists of participants in the North American Handmade Bicycle Show, or the Bespoked UK Handmade Bicycle Show. Another idea might be to contact Bosch or Shimano, they have shown willingness to work with framebuilders to provide CAD drawings of their motor mount dimensions to enable custom frames. Or buy a motor mount to give to a frame builder to work with, a Taiwanese company Allotec has a website you can search for "motor cabinet", these are imported to the US by a business in Portland, OR. I know of at least one framebuilder in England that makes a cargo frame with a generic mid-motor mount that has been built up with Shimano, TongSheng, and Bafang motors, and others are increasingly adapting their designs to better accommodate batteries.

Was the Soma Wolverine one of the Taiwanese frames you looked at? It looks like a good model for your needs, sliding dropouts, the Type A model can take a tapered steerer, but only the Type B has a rear triangle frame break, so presumably you would be able to use a Gates belt on the Type B but you would need a Veer split belt on the Type A to add a suspension fork.

 

[bjorsa]

While I appreciate your input, none of your suggestions came even close. Those bikes are totally different concepts, use Bafang motors or no motor at all, lack front suspension ... I could go on.
I'm grateful for the Allotec link!

 

[JRA]

I am feeling your pain in regards to mid drive kit motor Q factors, they all suck. However your wish list reads to me like what kind of Unicorn you want. Unless you go full bespoke builder that is. Good luck.

 

[bjorsa]

At the same time, my unicorn is steadily inching itself into mainstream cycling dreams. More and more brand churn out precisely the bike I'm after. Just look at the success of R&M and the rest of the german field of S-pedelec high-end randonneur-type bikes that unabashedly pamper highly paid commuter's sensitive asses. I would have thought one frame builder somewhere on the planet would have found a niche catering to us DIY wet dreamers. I can hardly google at all without stepping on a dozen high end DIY MTB frames filling just about the same needs, except I guess for cool young people. The market is there, no doubt.

Surely finding the right China custom carbon builder should settle matters?

 

[JRA]

You can name all the complete bikes you can google but as I read your original post you were looking for a "frame". I think that in the DIY marketplace you also might be a bit of a unicorn yourself which is perhaps why there are no stand alone frames being made available to the general public, although the companies that supply complete bikes get them from somewhere? And not to say if there was such a frame made available that others wouldn't want one.

Over time I have seen lots of calls on the various forums for frame sales so that end consumers can simply spec to their own requirements using components they have on hand or can source. Seems like it falls on deaf ears even in the push bike domain to me much less for ebikes that need a battery and motor that comes from another whole manufacturer that have their sales/service standards set on wholesale to manufacturers only....

If you decide to go to China with your idea having a complete/accurate frame design to send them would be my advice. If you just go with the concept as described above you will spend alot of time going back and forth which I can pretty much guarantee will end up frustrating you in the end.

Due to the proprietary nature of the Yamaha, Brose etc. motors you suggest it is a given that you will not be able to get ahold of one for your project. Your best bet is the Bafang M500/600 series system as they are being made available to the DIY market and gaining some respect in that arena.

 

[bjorsa]

I hear you. You're not wrong. And yes, I'm searching for a frame without components.
Annoys me that I can buy a mid drive MTB frame for whichever motor and fork, but not a commuter. The motors are all sold on ebay.de : Bosch, Shimano, Yamaha, Brose, Fazua all one click away.

 

[JRA]

"The motors are all sold on ebay.de : Bosch, Shimano, Yamaha, Brose, Fazua all one click away."

Out of curiosity I checked on this and while it is fact that you can buy a motor as indicated and perhaps a battery they are not going to be a complete plug and play system like the M5/600 are.

Your best bet would be to perhaps find a ruined frame with the electric components intact. But still doesn't get you to your goal.

I have spent some time in my life trying to get to the goal line in the bike world for what I "want" and had to punt pretty much each time. It can be a fun exercise to go for it though but as I indicated frustrating in the end if you end up with no result.

Or just bite the bullet and get a complete bike and start swapping in your desired parts and selling the take offs......chances are it will be cheaper in the end and faster to your goal.

 

[bjorsa]

Thanks JRA, your input has been very much appreciated. Food for thought.