Neppy's 3 year long minivelo / folding bike failed build

Ok, so here's the backstory on this first. 4 years ago, i set out to build a very comfortable, light, very fast full suspension downhill bike with a large range. I achieved every goal with that build - 40mph continuous with 60mph burst speed available, enough range to cross county lines and back, and supreme comfort over potholed pavement.

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The sticking point :lol: was every 26" bicycle tire on the market. Our streets are littered with goatheads for half of the year, which are approx 10mm long. I tried every single "flat proof" tire on the market and every single one failed. I tried tire liners. I tried slime & stans no tubes. $400 of tires and tire accessories later, i decided to give up. The thickest tire i found, a schwalbe marathon plus, only had 7mm of total rubber..

Instead of range anxiety, i developed tire anxiety. I would get a flat tube every other ride without fail, as i'd be picking up a few goatheads per mile, and eventually one would strike at the right angle, regardless of various experiments with an ideal tire pressure..

So, knowing that some scooter/motorcycle tires have 10mm or more of rubber, i set out to build a bike with 20" wheels and mount a 16" scooter tire to it. 17" and 18" motorcycle wheel builds just come out being far too heavy.



First try.. a Downtube 9FS. I sweet talked the owner of Downtube into selling me a demo unit after finding nothing but praise for the bike on the internet.

Upon opening the box, i was impressed by the dimensions of the bike. The wheelbase is similar to a large size frame, and with some adjustment, fit me pretty well. It appeared to be nicely overbuilt and i was pretty excited about finally having one of these.

Also, the bike looks like it easily accommodated 2.25-2.5 moped tires, and it had a standard 135mm rear dropout, so it is perfect for a hub motor setup!

The first ride was pretty revealing. The front suspension only compressed about half as far as the manufacturer claimed ( 40mm versus 20mm real travel ) and was basically useless as it'd bottom out and clunk on the smallest bump, regardless of the preload setting. The rear suspension is a very short spring, but was much more useful.

There was the usual flex in the handlebars that you'll find on nearly every folding bike on the market. The folding mechanism in the center was very solid. The real problem is the rear swingarm - i could feel flex in it as i pedaled or changed gears. This was the real deal breaker with this frame. I decided to put the ebike up on eBay.



Second attempt.. after looking at every minivelo on the market, i decided to try a Sundeal V2 out because of it's dimensions and the fact that it had a chromoly frame with standard rear dropouts. I figured that fitting a front suspension and a suspension seat post would be good enough, since scooter/moto tires provide a suspension of their own.

Truth is that this bike is much smaller than it appears and is advertised - way too small for me. The headtube is also a 1 inch threaded :/. The biggest deal breaker here though is the brakes and tire fitment. They put the tube the brake caliper mounts to very close to the tiny 1 inch tires, which rules out the possibility of fitting a wider caliper and thus a wider tire.

In addition, the headset came ungreased, and was partially cross threaded upon arrival. The box it came in had been stapled shut twice, so maybe this bike was a return at one point? but still.. totally unacceptable for a manufacturer to ship a bike in this state..

Off to eBay she goes.



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So.. third try's a charm, right? Being inspired by Recumpence's Cannondale Hooligan build, i found a used Hooligan on eBay for an eye watering $800, but was desperate to get this build going, so i paid the cash..

Dimensions are a little bit small for me, but doable with handlebar adjustments and maybe an aftermarket lean-back seat post.
The frame is SUPER sturdy and built like a tough little BMX bike.. big plus!
The bike came with 20 x 2.35 tires and would easily take a 16 x 2.5 scooter tire, so that is a win.

I had read the specs completely on this bike and was certain that it had standard 135mm QR dropouts.
Nope. It has a 12mm axle flat rear dropout... something i have never seen or heard of on a bike.. the rear dropout area does not allow for you to bolt on an external plate or plate + shim to remedy this easily. So a rear hub motor is out.

The bottom bracket is an odd size and the bike came with some kind of eccentric bottom bracket adapter to fit a standard size bottom bracket. Probably not a good situation for bolting a mid drive on.

Front fork is a super sturdy lefty fork. On these bikes, they have a proprietary headset and so it would require an aftermarket adapter to fit a standard 1 1/8 fork. So yes.. you could theoretically go for a front hub motor, but we all know the problems that come with a suspension fork and a hub motor..

It's almost as if the bike was built with preventing ebike conversion in mind.. :lol: ( unless you have a CNC shop at your beck and call! )



OK, what about other minivelos on the market that can accommodate suspension? there's the wildly expensive airnimal rhino, but looking at the frame, i suspect it will be flexy around the rear like the downtube. Rear dropouts might be designed around the IGH hub and thus be an odd size to fit a hub motor.. that option is out as well.



I was at interbike this year and saw this little beauty.. full suspension.. fits a tall adult.. light.. electric.. ticks all the boxes. Except nearly every part is proprietary 'cept for the pedals and grips. No DIY on this baby without a CNC shop.

So what have we learned here? well, if you're 6 feet tall.. forget these 20" wheel bikes as a whole.

I have decided that the only feasible way to go is weld a 2-3 inch dropout extension on a hardtail chromoly mountain bike. Far easier than playing with the dumpster-worthy stuff on the market.

So there ya go.. a cautionary tale for others looking to go this route. Hopefully i save some others some pain, suffering, and money..

Sounds like we need to design and build you a frame. :lol:

Hmmm...my Cannondale Hooligan 8s have normal rear 135QR axle setup. I have a nice little front Cute 100 on one of them. The other, I left unelectrified for grocery runs. Awesome bikes but hard to find..

Can't you put torque plate on the inside of the dropouts on the hooligan?

chvidgov.bc.ca said:

Hmmm...my Cannondale Hooligan 8s have normal rear 135QR axle setup. I have a nice little front Cute 100 on one of them. The other, I left unelectrified for grocery runs. Awesome bikes but hard to find..

Click to expand...

That's what i saw on the spec sheets. Wasn't what arrived at my door. I believe i have a 2011 model.
If you're interested in swapping your unelectrified 135mm QR model for my black one with the weird axle, send a PM.. i'll pay shipping plus a little thank you money . These go for $700-$900 on eBay and i don't wanna roll the dice on any more 20" frames.

tolkaNo said:

Can't you put torque plate on the inside of the dropouts on the hooligan?

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You could, but that wouldn't give you enough meat to hold the wheel. There isn't space to drill anything into the frame nor any bolts in good locations.. and that would limit you to smaller motors with weird axle sizes. I wanted the bike to peak to 45mph so i can ride on the fast roads with no bike lanes here.. a hub motor is ruled out by that.

I have a Rhino frame and it is seems pretty strong to me.
It is hard to tell in the pic how thick the plates that support the pivot bearings are but they are beefy.
I would say a hub motor should not pose any threat.
The dropouts spacing is 135mm, they are vertical but can be moved horizontally for wheel removal if no chain tensioner/deraileur is used.
I have some 2.45 BMX tires on mine and the only bottleneck are the mounts for the rear rim brake, i have to wiggle a little the wheel to pass through.
I agree it is expensive as funk. It cost me 1300$ for the frame only.

Maybe this one shows a little better the attachment of the rear triangle.
It doesn't look like much but i could not feel any flex at all with a 1500W mid drive.

Thanks a lot for that info.

No perceptible flex with a 1500w mid drive is pretty impressive, because i've felt mid drive flex on some 26er full suspension bikes with bbs02's on 800 peak watts. But perhaps it's the derailleur or the derailleur hanger doing the bending? hm..

But ideally i want to run around 4000W peak through the rear dropouts. Those adjustable rear drops are a bit of a concern.

$1300 isn't much for a specialty, low production volume frame with no competing product on the market.
I think i'll sit this one out and modify a frame instead because i'm not sure enough about this one to drop the big coin on it. Already had enough trouble.

But really, thanks again. I could not find much in the ways of reviews, etc on this frame.. helpful to know it's probably an option.

Thinking about it for a moment, the bottom bracket is part of the rear triangle structure (subframe? )so there can't be any flex between it and the frame since there isn't any torque transfered to it.
But the whole frame seems to have been designed with folding into a compact form factor foremost so the geometry is not best suited for a taller rider.
The top tube is very short so a long handlebar stem is needed to push the handlebars forward where they need to be for a decent riding position and some kind of fork steerer tube extension or riser bars in order not to have the handlebars too low vs the seat hight.
I am 5'10" and fairly comfortable on it.
Still a work in progress as with most of my stuff which is never ending.

The picture of my last big DIY build at the top of the thread should be telling about my own personal geometry. The handlebars forward 1 foot and up 1 foot VS. the stock positioning. This is on an extra large frame.

Shame that the airnimal required those modifications for a guy who is a bit shorter.. I know now that it won't work for me.

Time to get something welded up!

Sorry to hear (read) Nep... Saw "velo" (Giggle Search for images full of bicycles) and my first though was veloMOBILE (change Giggle Search for examples). In your first post in this thread you wrote "very comfortable, light, very fast full suspension uphill [hehe] bike with a large range". See maybe aerodynamics re "higher" speeds?

And locally, have "goatheads" too... as plenty of car parts watt litter the landscape, broken glass, etc etc... HAVE pumped inner tubes w/plenty of liquid latex, and "so far, so good" in over one year of travels. Next am gonna try "heavy"-ier solid foam-filled tires. Thing about veloMOBILES... Yah gots yer air conditioning. ... and drink holders... ... and more aero at "higher" speeds (see energy efficiency).

And re weight overall... (other than pilot I mean...) fer a shell I'd laminate the body using a "foam sandwich" plastic construction. Like my last sailboat was constructed:


... watt was VERY "fast" in sailboat terms.

So. Velo? ... or VeloMOBILE? :wink:

EDIT (again):



Seen here:
The Fastest Bicycle on Earth
https://motherboard.vice.com/en_us/article/pgaq4z/the-fastest-bicycle-on-earth

... getting closer? Unsure re number of drinkholders...

I'm okay with wasting watts to the low coefficient of drag.
I hope to be reborn as a teardrop-shaped creature, such as fish, in the next life.

Anyway, if the collective wisdom of ES can't bail me out on this issue, there's only one way out.
I'm buying a chromoly frame and getting dropout extensions made. Period.

Watch this space next spring.

HOLD UP....

I have still been on the hunt since the last post, after selling off the cheap sunbike and the cannondale hooligan.
I found out that semi recumbents typically have odd wheel sizes..
IE.. 26 inch rear, 20 inch front.
20 inch rear, 16 inch front.

But had major difficulty finding one that had suspension, until a few days ago.

I found the Cannondale Bent / Cannondale Easy Rider.. ( discontinued, but a few pop up on eBay from time to time. )



And the Maxarya ray 1/2, which is currently in production and sort of a mashup of bike-e and cannondale designs..
http://maxarya.com/ray-1/



Through interrogating a guy on eBay selling the cannondale, it looks like the bike takes at least a 2.25 inch wheel, which gets us into scooter tire territory. Bonus if it takes a 2.5"! It also has a nice flat dropout surface. So i bought the bike today.

I also got the Maxarya company on the line through facebook, and the rear of the bike has over 3 inches of clearance for a tire. So you could put a tire on that's wide enough to rub against your chain - ok, that's enough clearance



There's also a lot of other semi recumbents with this wheel layout, but few of them have suspension, although they typically come with long steel frames, thus some of the bounce is dampened. I want to do at least 30 mph, ideally more, so rear suspension was a bare minimum for me.

Surprised nobody suggested this to me, but semi recumbents haven't got a lot of love lately so i will probably turn into their champion.

I'm interested to see what you come up with Funds have delayed my recumbent plans for this year.

Find something that works and stick to it.

The continuation of this story is here. I'm building a semi recumbent:
https://endless-sphere.com/forums/viewtopic.php?f=6&t=98401

https://www.amazon.ca/Dahon-Jetstream-Urbanite-Folding-Bicycle/dp/B00O19DKCQ

Dahon jettstream might be a good donor bike.

Damn it, you already kicked out the hooligan. Might be a smart choice but i'd considered CNC milling some dropout adapters for you

Hate the "invent a new standard" norm in the bike industry, gets you every time.

TOLM said:

https://www.amazon.ca/Dahon-Jetstream-Urbanite-Folding-Bicycle/dp/B00O19DKCQ

Dahon jettstream might be a good donor bike.

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I saw that bike. Couldn't find any specs on the tire width or rear dropout width. I suspect it's a wobbly feeling ride with too short of a wheelbase and not enough arm reach. Not meant for high speeds or comfort for us taller folks.

I'm sort of happy this was a disaster because it lead me to the semi recumbent world.
I have zero interest in playing with these kinds of bikes again. Every single one had a poor ride quality.

neptronix said:

TOLM said:

https://www.amazon.ca/Dahon-Jetstream-Urbanite-Folding-Bicycle/dp/B00O19DKCQ

Dahon jettstream might be a good donor bike.

Click to expand...

I saw that bike. Couldn't find any specs on the tire width or rear dropout width. I suspect it's a wobbly feeling ride with too short of a wheelbase and not enough arm reach. Not meant for high speeds or comfort for us taller folks.

I'm sort of happy this was a disaster because it lead me to the semi recumbent world.
I have zero interest in playing with these kinds of bikes again. Every single one had a poor ride quality.

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Haha.. I was able to find all info that i needed including, on top of what you've.mentioned including the type of headset as i was swapping a fork, etc prior to buying. Looks like you should do your due dilligence better lol. And again, there are pretty well built folding bikes out there. My other folder is a tern verge x30h: no wobble or reach issues. As another example.

I did my due diligence on each of these bikes, but there was misinformation, lack of information, or no information for each of them.

I spent hours on the phone with the owner of downtube before i bought one of his bikes, and looked at every single review i could find on the internet. No mention of all the problems i had, just shining reviews everywhere.

I asked the ebay seller a dozen questions about the cannondale before i bought it. I found canondale's spec sheets per year. It was made certain it had the dropouts i was looking for before i bought it, and it didn't. The bike was one year off between a spec change apparently.

The silver bike? i saw good reviews and was frustrated after the second year of not riding because of goatheads in my area and bought it on a whim thinking that maybe i'd be okay with a slow ride because it is better to ride slowly than not at all. Now that was a mistake i could have avoided.

You can laugh at me all you want but i've been building ebikes for decades and never had so many problems trying to find a decent bike/frame to fit this task.
I think buying some more expensive Dahons or an Airnimal would have made the mistake of trying to use this kind of bike even more expensive than playing with cheaper bikes. A big problem is that there are zero retailers of high end folding bikes in my area, so there was no chance to even try one, just throw ~$2000 at the internet and see if it sticks..

It was 100x easier to find a suitable semi recumbent bicycle, and as a bonus, nobody lied about or omitted specs along the way.

IMHO, this type of bike doesn't seem to be built in a serious way, ever. They're designed to be short distance rides for crowded urban environments, and all generally have a very upright, anti-aerodynamic positioning. They do not tend to come in large sizes. Suspension is an afterthought even though the short wheelbase 20 inch wheel setup is a real bone rattler.

When i get settled in and get myself a TIG welder, i'll revisit this idea, because i still like the idea of a study 45mph bike you can throw in your trunk.... like so

TOLM said:

And again, there are pretty well built folding bikes out there. My other folder is a tern verge x30h: no wobble or reach issues. As another example.

Click to expand...

All small wheeled folders are critically compromised for tall riders. Yes, they can be ridden, but it's in a way that suggests, well, you know....



There's no technical reason that folders couldn't be made to fit tall riders, but that would make them a little larger when they're folded. Improved design and manufacturing could make them stiffer and better-handling, too. But they'd be more expensive. Folding bikes aren't for riders anyway. They're made as gifts for other vehicles, like cars and trains.

Yeah, i found that out the hard way.

Japanese minivelos are some of the best. They're designed with a different goal in mind - to fit inside a 5 square foot house . Some are built very well.



Because Japan has an insane urban density, any feature that would allow high speeds is missing. You will find 1 inch fork tubes, oldschool caliper brakes, but paradoxically, sometimes full suspension and fat tires, as seen above.

But they've got cool minivelos for days over there; though you'll have to play the rakuten lottery with Japanese retailers to get your hands on one. Probably tougher to do than playing the aliexpress lottery.

I decided to hang my hat up before doing that. Shipping a bike back and forth from the USA to Japan would cost more than the bicycle itself.

You and I am looking for something similar regarding a bike.

For me it will be with a long wheelbase as long as a touring motorcycle, have full suspension, 3 wheels even better as long as it leans ( See Piaggio Mp3 for tadpole and Honda Gyro from years past for Delta )

This will require a design and the use of tubing like what Hang Gliders use, not round tubes , use square or rectangle tubes that fit inside of each other , are are held in place with Delrin and AN bolts . A study of how Hang Gliders / Microlights etc. will help you design what you want.

Welding, and/or finding a machinist that can make the plugs and adapters .

If using only two wheels make your own Girder fork . ( you could even then have a high torque motor on the front )

neptronix said:

It was 100x easier to find a suitable semi recumbent bicycle, and as a bonus, nobody lied about or omitted specs along the way.

IMHO, this type of bike doesn't seem to be built in a serious way, ever. They're designed to be short distance rides for crowded urban environments, and all generally have a very upright, anti-aerodynamic positioning. They do not tend to come in large sizes. Suspension is an afterthought even though the short wheelbase 20 inch wheel setup is a real bone rattler.

When i get settled in and get myself a TIG welder, i'll revisit this idea, because i still like the idea of a study 45mph bike you can throw in your trunk.... like so

Click to expand...

Kinda like Simon Williams' creation? an upright trike?
( notice the two hub motors out back )