hybrid suspended tadpole recumbent

[BarelyAWake]

Out n'about & wanderin' the interwebs I stumbled on this forum & had the thought that in fact my latest project may have more in common with the karts here then the motorized bicy... erm tricycle it's meant to be lol, some of you may even recognize a repurposed component or two as I tried to keep it to as many commonly available parts as possible, to ease construction, maintenance & repair - such as the chopped & dropped Yerf Dog front end for example.

While it's not quite finished yet, temptation got the best of me and I just couldn't resist any longer, so this past weekend I dragged it out just for a quick initial test run around the lot... and while it went far far better than expected, I figured I'd join up here & babble some to exchange ideas, thoughts & suggestions - as it's still winter in Maine & we just got another good 3/4' of the blasted white stuff, it's gonna be a while before it gets back outside for more testing so now's the time for all those last minute changes & all those little forgotten bits.

To give ya an idea of my madness, overall this build is mostly for the sheer experimentation, an excuse to tinker w/both a four stroke 49cc Lifan (CRF50 clone) and a 36v 1000w electric drive as a hybrid in a suspended recumbent tadpole configuration. My "best case scenario" is something that is snappy off the line yet uses little fuel for my commute & offering comfort & reliability for the long hauls (daydreamin' of cross country trips & camping adventures ofc) - but really more than anything else, just the fun & education of tryin' ta make all the pieces fit;



photo album
youtube vids
build log

 

[landuse]

Welcome to the forum BarelyAwake. I recognise the name from the other forum. I love your recumbent

 

[Doc Sprocket]

Wow- That is pretty trippy, isn't it? Welcome to our little spot in etherland!

 

[BarelyAWake]

Thanks landuse & toystory, yea it's a bit of an odd beastie & it really doesn't quite fit in anywhere lol, still we've an empty lot nearby that's used for both "official" & unofficial kart races & while they'll doubtlessly smoke me - I'm so looking forward to at least trying on the sweet serpentine track they set up a coupla times a year

 

[landuse]

Have yu measured how fast you can go yet on your recumbent

 

[BarelyAWake]

Not yet, not only was this just an impulsive "quickie" test that wasn't s'posed to happen in the first place lol, there were ofc some teething pains - as it turns out I'd bunged up a jackshaft bearing (for transfer of pedal & gas power) the last time I removed it due to the keyed shaft being somewhat stuck & my impatience... not too shabby really as the one failure was only an $8 part I'd broken months ago & just didn't know it. As a result I eventually limited myself to using the electric drive only so I could at least evaluate everything I was really worried about, the important stuff that can't be just "fixed" with replacement parts that concerned me, the math - the ergonomics, handling characteristics & suspension, clearance & turning radius, emergency braking, the weight & balance - all those pesky design details that I'd had to mostly guess & hope for the best, the ones that if faulty I'd have to chop up the frame to change.

Which all seems to have turned out to be fine, even better than fine & in fact I was surprised at just how well everything seems to work. Summoning up my courage I took the laps a lil faster each time to see how she did in the hard, slightly inclined turns of the lot. I was getting some sidewall roll from the front tires, but they were a bit low in pressure so I aired them up to 60psi (max) and tried it again. Now I was able to take these turns at least as fast as I could with my two-wheelers and still the taddy felt rock-solid stable, with me leaning a bit to help ofc. I wanted to try it even faster, but I was starting to get sketched out given there's not a lot of room in the lot & ofc it's an untried vehicle, some amount of restraint is prolly a good idea (or so I keep trying to tell myself).

Once safely tucked away in the shop again I thought about the one handling characteristic I wasn't completely overjoyed with - the front tire sidewall rollover. I thought about just upgrading the tires to take 90psi, but wondered about high speed turns, potholes & pinch flats. Bustin' out the laptop I started hunting around for wider 20" BMX rims and surprise surprise - Alex rims now had the exact same DX32 double wall alloy I'd gotten for the rear (26") in a 20" version, more than I could have asked for & in fact wider than I'd hoped to find I bought a set of those puppies almost before the page had finished loading...

They're gonna be monsters lol;

2x Alex DX32 20" 36h Black, 39.1mm Width


So as much as I'd love to do some speed trials, given it's snowed again & I've gotten some replacement & upgrade parts (the new front wheelset is being built as we speak) - I'm back to tinkerin' minor details & waiting for spring... real spring that is, not the silly false promises of that lying calender lol

 

[landuse]

It sounds like you have everything working nicely for you. Did it feel as if you were putting to much lateral stress on your front wheels? I know that bicycle wheels are not usually designed to take those stresses, and with a recumbent the wheels can't 'lean' like they usually would

 

[BarelyAWake]

Yep, that's exactly it - the front tire & rim combo was a bad match for lateral stresses, not because the wheels couldn't take it (36 spoke double wall "freestyle" BMX rims), but because I erred in judgement early on when I bought them.

The rims were simply too narrow for the size tire I need to run (weight & speed), because of that in cross section the tire looked almost like an O with the sidewalls diving steeply in to the bead, with the far wider rims I just got the cross section should look a lot more like a D (on it's side ofc), flattening both the contact patch and the sidewalls, which should tighten things up nicely *crosses fingers*

It's kinda hard to see w/just pics but this;

vs this:

 

[BarelyAWake]

Jackshaft oopsie sorted & my new front rims built, this time indexed out (spoke/hub alignment) as much as safely possible to widen the front wheelbase width & gained just a lil over 3/4" (10mm each side = 0.39"x2 = 20mm or 0.78"). The thing was rock stable in turns already, but every lil bit helps & they'd originally been built indexed centered, typical for bicycles.

Dragged the thing outside into a balmy 30°F "spring" morning, I started out doing laps in the lot at 5:30am, tiring of the NASCAR action & everything seeming to be holding together I took off down the road to the corner inconvenience store to grab a cawfee and ran into a problem...

...I didn't get my cawfee till almost an hour later, I made it to the store just fine, never made in the door as apparently the public finds this thing somewhat interesting, I hadn't even managed to shut her down and had the store clerk, a random customer & a cop all eyeballin' every inch & askin' a billion questions while I was trying to clean the windsnot off my face... well 'cept the cop whom just nodded, said "nice" with a smile & wandered off to do whatever law officers do 6am Easter Sunday lol

About an hour & a half later (one small cawfee?) I was left w/a dilemma, I didn't really want to head off to parts unknown with a test vehicle but I really didn't feel like doing anymore lot laps & after some musing decided it was time to take the back road I always use for shakedown & speed runs, hilly & twisty but with pavement that's mostly ok I've a friend that lives around the halfway point in case Murphy attacks... a touch early for a surprise visit maybe, but I didn't think they'd mind.

It's quite a rush riding this thing, feet first & *** less than a foot off the ground I'm comfy but disconcerted and even pedal speeds feels like mach 1, starting out with a long but gentle uphill grade the lil 49cc four stroke & electric worked in harmony even while I tried to figure out which gear range worked best for the incline. Clearing the hill top the road goes into a coupla gentle curves, a mild downhill & then another long uphill, this one no joke it gets gradually steeper & it drops my 66cc two smokers down to 15mph, my ebike to about 11 (if I don't help) - but the hybrid tadpole shrugged it off & maintained 20 to 25mph all the way up, which may not sound amazing - but then again none of my two smokers could manage that, not even my geared & built "fast" one, the torque advantage of both the electric and the four stroke really coming into play on hills, the takeoff acceleration from a stop impressive as well.

A couple more unremarkable hills, a few more twisties and I found myself at the turn to my friends house, the turn drops right into a short but crazy steep downhill, the one I blame for so many burned out tires as I try to slow at the base to cut into my friend's driveway - no worries with the taddy as the front discs work wonderfully well, doubled up as they are with the two front wheels n'all... but it was getting back up it from a near dead stop that gave me pause as no bike I've built can take that monster, every single one requires me to stand on the pedals & pedaling as furiously hard as I can just to make it to the top.

Ah well I figured, I'll chill w/my friend and see what happens & after some time shootin' the bull & checkin' the ride over for problems it was time to try - and after making a big deal about how "I might not make it up, don't worry", crossing my fingers & hoping I wasn't about to smoke the ehub or pop the four smoker I dropped her down into low/low range and...

...trucked right on up that hill like nobody's business, I didn't even pedal a stroke! Stunned I sat at the intersection at the top for a moment thinking "did that just happen?" & chuckling, shifted into cruse range & took off, still laughing to myself, my foolishness & what to all appearances seems like a successful build FTW

Not that the tinkerin' is over ofc, not by a long shot I'd just doubled width in rims, lightly wider wheelbase and while the results were amazing with no sidewall flex or rollover, I've still got to adjust the alignment as it's only eyeballed & I'm scrubbing, which makes it a lil twitchy, drags down my speed & wears the fronts - given that and my "testing phase" heeby-jeebys, not to mention this is the first tadpole recumbent, or any recumbent I've ever ridden, I didn't exceed 30mph... which again as it's just a 49cc four stroke really isn't bad at all (e assist konks out at about 25), she had more but I wasn't ready for that yet, time enough for speed tests after I weld my rear brake caliper mount on & sort the alignment.

Still, a good day indeed lol;

new rims: vs old:

Out n'about at last;


Sorry, no vids at all this time - although had the cam & tripod with me I was so preoccupied it just didn't happen, I'm sure ya'll understand heh

 

[landuse]

It sounds as if you had an awsome ride. You must be really happy it can handle all that you have thrown at it. The combination of gas and electric seems to work for you.

Get a vid up when you have a chance. I would love to see how this thing rides

 

[BarelyAWake]

I am landuse, relieved too as honestly - there was a terrible amount of improvisation, guesswork, winging it & hoping for the best while I was building this thing lol

I'll try to get some vids shot this weekend if all goes well, for now I just spent a couple few hours fiddlin' around with the alignment and a coupla other minor whatsits, come dawn I'll be takin' the taddy for the work commute for the first time.

Thing is as psyched as I am I just realized I've no cargo carrying ability w/this thing yet... not really sure what I'm gonna do with my lunch & trusty thermos...

...ah well, these are "problems" I really don't mind at all heh

 

[landuse]

I am landuse, relieved too as honestly - there was a terrible amount of improvisation, guesswork, winging it & hoping for the best while I was building this thing lol

I'll try to get some vids shot this weekend if all goes well, for now I just spent a couple few hours fiddlin' around with the alignment and a coupla other minor whatsits, come dawn I'll be takin' the taddy for the work commute for the first time.

Thing is as psyched as I am I just realized I've no cargo carrying ability w/this thing yet... not really sure what I'm gonna do with my lunch & trusty thermos...

...ah well, these are "problems" I really don't mind at all heh

I was just wondering....is this legal in Maine, or are you going to have to be dodging cops?

 

[BarelyAWake]

Well, it's a tricky gray area as it's a multi-motor and there's no provision for hybrids as motorized bicycles or mopeds - but I was very careful to keep it compliant otherwise as either a legal motorized bicycle, or if I choose to register it - as a moped, which was another reason I went through the effort of full lighting, w/blinkers, brake light & even a horn...

...I figured it might come in handy to have a plate on it if/when I decide to do some serious cross country trips as it's weird lookin' and the legal standing of motorized bicycles is anything other than uniform, it varies so much from state to state there's no way to adhere to them all *shrug*

Should the hybrid aspect prove legally problematic, that's easy enough to fix - it's just a simple matter of swapping the rear out for a regular 26" 7 speed mountain bike wheel & that's it

 

[BarelyAWake]

Threw together a test ride vid, the original footage helped immensely with diagnostics;

www.youtube.com/watch?v=bNLTLRx8sTI

 

[Desertduler]

So cool! Good job I love it!

 

[BarelyAWake]

Thanks Desertduler! I wondered if it was an appropriate build to share here, but then I thought "it's pretty dang close to a kart, heck it's got kart parts" lol, this place helped me w/the Yerf Dog info (A arms/bushings) so I figured why not

 

[landuse]

This is JUST the place to share your recumbent. I have seen some pretty whacky build on this site. As long as it has some wheels and an engine, we are happy!!

BarelyAwake, I liked your last vid

 

[Desertduler]

Thanks Desertduler! I wondered if it was an appropriate build to share here, but then I thought "it's pretty dang close to a kart, heck it's got kart parts" lol, this place helped me w/the Yerf Dog info (A arms/bushings) so I figured why not

I am glad you have it posted here so I was able to see it! I am sure other people feel the same way you had alot to figure out on that machine and you used your head and came up with something different not just a cookie cutter project like I said very cool and good job I am sure it was fun to come up with the idea and build it very innovative and it looks like it is fun to drive I am all about different!

 

[BarelyAWake]

It's defo "different" heh & yea, it's getting to be more and more fun to ride as I figure it out & learn the thing - glad ya'll like it



...been a bit busy lately, but I've been tinkerin' away the little stuff & riding when I can - it's all down to detail work & fine tuning now, stuff like making this spring loaded chain tensioner out of some scrap aluminum, a chunk of StarBoard (fancy name for cutting board plastic) & a spring stolen out of a squeeze clamp.

I've only put about twenty miles on the tensioner but it seems to be working out well, I may replace the ramp with a wheel at some point just because I can hear it "ticking" as the links pass over it *shrug* then again I might just get used to it lol

I also made an inner heat shield for the right side saddlebag, as that's the side with the exhaust system. It was a gamble but it's also the only place I can really put any cargo carrying so I had to give it a shot. Putting a metal guard over the pipe was easy, but it wouldn't be enough so a took a bit of heavy fiberglass mat, trimmed it 1/2" smaller than the back of the bag & stuck it to a sheet of self-adhesive heat guard material (auto parts), sticking the thing to the saddlebag I then sealed the edges with vinyl sealant to make sure it stays put, adding tie downs to the bottom of the bags while I was at it.

I worried it'd not be enough to protect the bag & it's contents from the hot exhaust pipe, which other than that metal guard it's in direct contact with. Yet as it turns out the inside of the bag doesn't even get to body temperature no matter if it's sitting there idling or screaming around near redline, it worked out far better than expected, a relief as a bag on fire would be bad news lol;



...& more testing, this time the main reason why I built the thing.

I was planning to build myself a custom trailer, but time's pressing with spring finally here & I'll save that lil project for another time. So, I just bought a cheap one instead: http://www.amazon.com/Aosom-Wanderer-Bicycle-Luggage-Trailer/dp/B0083JHEG8

...which may have been a mistake as it's a total piece of junk. The welds are shoddy, the tubing insanely thin, the wheels were a bad joke & the offset on the hitch arm was way too long putting the trailer offset, out in traffic naturally. The whole thing is so poorly designed with no thought given to any actual use, even aside from it's low quality it's just silly with a ton of wasted space for the "convenience" of being able to fold it up to not much smaller at all - needless to say I don't recommend it.

Anyway, it gave me something to work with & after a couple of sessions in the shop I've fixed some of the issues and it'll do well enough for now. The first test run with it was with Mongo the ebike & the weekly bachelor chow run. Pulling it empty is exciting to say the least - unsuspended it bounces all over the place with every little bump & pothole, but it does seem inclined to stay upright, even so I'll prolly relocate the axles to lower the center of mass as it just seems sketchy.

I hadn't ever had or used a bike trailer before and it's dang odd but laden with a week's worth of munchies it was far better behaved, trundling along behind the ebike like it's supposed to... interestingly it doesn't have that much an effect on the ebike's preformance, about the same as the difference between knobby tires & semi-slicks (3mph), even with it's load of foodstuffs I only lost 4mph on the flats - not bad at all really, I expected worse.

That's not why I got it though, heck I've been getting groceries with motorized bikes rain, snow or shine for years now and I've never needed or wanted a trailer for such mundane tasks as that - nope, I need a trailer for far more interesting stuff, namely the long-distance wanderabouts & camping trips I built the taddy for.

With that in mind I loaded up the trailer with a bunch of random heavy stuff & my honkin' big tent - bigger than I wanted but it was on sale, it's tall enough for me to stand up in & best yet, the screened section is just big enough to park the taddy in, keepin' it safe from the elements & lookie-loos... so I ended up with a "two room cabin w/an attached garage" instead of the little pup tent I meant to get lol;



http://www.amazon.com/Coleman-WeatherMaster-Screened-6-Tent/dp/B001TS6WWC

Anyhoo, the taddy pulled it with ease - so much so it's a bit freaky as I can't even tell it's there, no matter the fact it was overloaded for testing with a lot of heavy tools I'd never need to bring, a bag of books & a bunch of stuff that was just in it for the weight. I chose a rough, pothole riddled dirt road nearby to see if I could break it - I didn't go crazy as the taddy itself is a street machine but it went quite well. I stripped an axle nut, but I'd done that earlier when attaching the hitch and it only served to remind me to replace the cheesium alloy with some quality marine grade fasteners I had but forgot about lol;

http://i305.photobucket.com/albums/nn210/Serenity151/tad/IMG_3467_zpsa9e96380.jpg

In review, it seems the thought of a four stroke/electric hybrid for torque was exactly what's needed - I could have built a much faster two smoker, but it's plenty fast enough & far better yet, consistent. It seems no matter the hill or trailer weight, it just keeps truckin' along - crazy steep incline from a dead stop? Trailer with a hundred pounds of crap? NP - drop a gear range & away we go just to see what's around the next bend

 

[landuse]

Things are just getting better with your recumbent I see. You seem to be having a blast