Blue Dream: Maxarya Ray 2 Semi Recumbent w/high eff mid drive

Scrounged up some cash and put some orders in.

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Will test the 165mm wide springer fork + super wide BB combination to see if it fits. If it does, some high quality forks fit & i plan to maximize the fork quality because the suspension needs as much help as it can get. The only question is if this extra width will aggravate my legs.

The 28mm clamps are for side protection bars mounted to the seat. Plan to bolt BMX pegs with a visible color to them, then cut them so that they extend no further than the handlebars. This way, the bike will want to lay flat when dumped.

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So the bike is back to under construction.

Lately i've just been riding the pedal bike and enjoying the exercise. I can tell my quads are building up and i'm dropping weight. It's good! once i get back on the bike, i should have a better power to weight ratio :)
 
Some updates.
Still waiting on this 18 inch wheel build, WTF, LBS!

Ordered a 20 x 1.75" Michelin Country Jr. tire and a 20 x 1.75" Tannus Armor. The Armor appears to be 19 inches in diameter, and slips inside the tire A LOT. It's marked the same ISO dimension as the tire, so i think they screwed this up at the factory. The supplied smaller inner tube is a misfit also. Back to the supplier i guess.

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The michelin tire is a super squishy kid's tire with a very grippy pattern. I figured switching from hardish to wimpy rubber would be a +1 to frontend damping, and i was right. At 32PSI, the judder level, on a 1-10 scale, is a 5. I could reduce this PSI, but... i want the safety.

Grip wise, on gravel, the mooshy 1.75" front tire also outperforms the 2.0" schwalbe big apple by a lot. I'm very surprised. This is a good temporary setup :)

I also swapped out the rear spring for a Rockshox Monarch R. The improvement in ride quality is smaller than expected, but notable, and this will help counterbalance the lower stiction, bigger stanchion, springer front fork i plan to put on the front.

Current pic w/o battery:

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I did install the safety bars. They were a bit too long on the lay-down test, but it appears i'm barking up the right tree.

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I'm thinking that i cut these BMX pegs in half and bolt some PVC pipe w/angles to them & link those to the middle of the frame somehow. That will protect my legs during this theoretical laydown, the pipe will be designed to bend and take much of the crashing stress off the frame. And it would be cheap to replace after a crash.

The only negative is how wide this bike is, it barely fits through a door, maneuvering it around a small apartment requires some 16 point turns. The pipes on the side will worsen that.

I'm sure getting in/out of it will be more of a pain. Same with putting a foot out to stop at a light.

And yeah the bike will look funny.

But these seem like small prices to pay for the ability to go sideways and come out of it without a scratch!
 
Emailed Tannus. They say stretch it out. They were right.
I had a professional install it because it looked daunting. Dude did it quick!

Juddering on crappy pavement is down from a 5 to a 4.5 at 30PSI.
The rumble is there, but the intensity of it is lower, and it's smoothed out very slightly.
Added rolling resistance on the front wheel is imperceptible so far.

I think the truth is, due to the weight balance, the front foam, like the suspension, can't do much for me.
A soft moped tire on the front could maybe cut the judder factor down to a 4, which is sort of acceptable. I think it would do this without a big rolling resistance penalty, due to the very low rubber deformation..

This would mean moving the tire diameter even higher, which helps against judder too. Maybe we're at a judder factor of 3.5-3.75 by then. Which is at least okayish.

From current:
20" x 1.75" front, 20" x 2.4" rear
to
20" x 2.25" front, 20 x 2.8" rear
= +0.4" front, +0.4" rear

To get similar diameter with an 18", a 14 x 3.0" scooter tire. Doable!

Okay looks like we're turning this into more of a fatbike out of necessity!
 
18" wheel is here and it looks cool, hanging onto it if i chose to go with the other suspension fork.
20 x 2.8 tire and tube ordered.

maxarya sent out an email talking about a redesigned frame, so i gave them a call asking about bottom bracket placement and hey say they have an electric version with a custom frame that addresses it.

Emailed them detailed feedback about the weight balance/NVH issues i've been trying to counter for years now and they are interested in maybe building me a custom frame. More to come!
 
Got the Schwalbe 20" x 2.8" and fitted it.

Disappointed. Super flimsy casing, thin protection. The extrusions ( knobs ) are decently hard, but overall way less less puncture proof than these Kendas. 1.1lbs should have been a hint.

After mounting, i notice the front fork compressing a bit more when i sit on the bike.

There is 3mm of additional space left in the frame, which is a little over .1 inch.
Means i can barely fit a 20 x 3.0. Pictured is the current candidate.
The tire weighs 2.85lbs, so it's going to nip at my efficiency versus the Kenda cargo.

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With this size tire in the back, i could go up to 2.35" in the front w/o moving the weight balance in a negative direction. If i remove the 10mm headtube spacer, a 2.8" in the front is no big deal.

Now i have room to experiment with a better and taller fork without abandoning the 20" front wheel, with the downside that the bike is basically 12.5mm taller than stock.

Weather wise, it's pretending to be the middle of winter out here. We should have a few days of 45-50f this week, so i'm going to test ride this configuration soon to see if the angle change affected the judder problem.
 
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neptronix said:
There is 3mm of additional space left in the frame, which is a little over .1 inch.
Means i can barely fit a 20 x 3.0.
Click to expand...

It's a long honored tradition in MTB circles to use an angle grinder to trim the shoulder knobs of tires that would otherwise rub on the frame.
 
Chalo said:
It's a long honored tradition in MTB circles to use an angle grinder to trim the shoulder knobs of tires that would otherwise rub on the frame.
Click to expand...
Don you have a method of minimizing wobble when tire is mounted?
 
maiz said:
Don you have a method of minimizing wobble when tire is mounted?
Click to expand...
Soapy water?

If the wheel is loose or out of true, I fix that first. Then if the tire won't seat evenly, I apply soapy water to the bead on both sides and then inflate to the maximum rated pressure before reducing to the desired pressure. No tire is perfectly shaped, but this method usually allows it to seat as evenly as possible.
 
neptronix said:
Juddering on crappy pavement is down from a 5 to a 4.5 at 30PSI
Click to expand...
I'm still unclear what you mean by "juttering". MW states: "The meaning of JUDDER is to vibrate with intensity." Is it present on smooth asphalt?... Is it initiated by, or aggravated by irregular road surface?

Is the Schwalbe 2.8 you refer the Super Moto-X?
 
Yes that matches my definition. Absent on smooth asphalt, but we don't have much of that. We have crappy mountain state roads, smooth asphalt is an edge case.
Can feel all of it on the front end, the rear end is very quiet and non eventful.

The problem existed before any modifications, the stock rigid front fork was more juddery and astoundingly loud on slow pedal power.

The Schwalbe 2.8 is the super moto-x, yeah.
 
neptronix said:
...Absent on smooth asphalt,....
Click to expand...
This would likely rule-out imbalanced wheel/tire combo, and instead, points to insufficient wheel damping. But can also be aggravated by insufficient sprung mass (insufficient loading on the front wheel).

Yes, I realize I'm being persistently redundant, and I apologize,... but it needs to be stressed... that your rig's wheelbase is MUCH too short for your leg length and body mass - you know that. I encourage you to pull the damn rear swing arm off and take it too a fabricator and tell he to duplicate it, but lengthen it 4-5".

Edit:

Around 2005-6, I built a TE clone for my brother-in-law (image below). He is well over 6' and weighs near 250 lbs. The wheelbase is just north of 70". He rode that 'bent for well over 5 years... mostly on windy MUPS. He had to quit 2-wheelers all together because of balance issues and degrading knees.

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Yeah, not a tire balance issue. You're on point with the assessment.

Prev. judder assessments have been made without the front battery on and me sitting on seat adjustment setting 2 of 3, so a little disadvantaged.
I can move forward by 0.5 inches with different front gearing and aiming the front eccentric bb forward instead of down.

But yeah i'm basically at the limit of what can be done other than 2xing my battery up front. However, the front fork has massively bad stiction, so that's not helping.

I've had a hell of a time finding a fabricator locally, so much that i've given up. An extended swingarm would be awesome. I wonder if someone here on the forum would be willing to take mine and fab me a new one.
 
Cowardlyduck said:
I would do this for you for just the cost of materials if you lived closer!
Click to expand...

How good are you at doing this on a scale of 1 to 10?

I'd be happy to pay at least a homey hookup labor rate and shipping both ways on top of materials.

My cannondale recumbent could use a new rear swingarm also, i have two i can send, one has nasty zebra stripe cuts in it, the other has rounded bolt holes where the shock connects. Between the two you should be able to get accurate dimensions.

It would be badass to get that bike running again. 20" up front and 24" rear is possible on this frame.
The bike has been collecting dust under my bed for 5 years now.
 
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Have you done a weight balance check ?
 
PaPaSteve said:
Have you done a weight balance check ?
Click to expand...

No. But i couldn't help but try the test since you planted the seed in my mind.

I sat on it and put me + the bike on a scale. One leg is on the pedal in this scenario.
Note: this 20 x 1.75" wheel on the front and 20 x 2.8" on the back, so i'm forward biased more than before.

Rear wheel, laying back, seat setting 2: 170lbs
Front wheel, laying back:, seat setting 2 ( middle backward ) ~65lbs
Front wheel, imitating seat setting 1 ( most forward ): ~75lbs
+ 52v 19.5ah battery = 11lbs, let's be pessimistic and say 7.5lbs of that is on the front axle.

So, best case scenario with seat setting 1 and battery on:
172.5lbs rear, 82.5lbs front.
Weight balance is 32.3% front, 67.64% rear.

Seat setting 2 and battery on:
Weight balance is 28.43% front, 71.57% rear

Abysmal. No wonder i am scrounging to add up tiny front axle NVH gains here.


You guys are right. This bike does need a +4 inch swingarm.

In the meantime, i want to squeeze out every ounce of improvement i can make.

I will begrudgingly move the seat forward and accept the aerodynamic loss. A front bubble is now a lot more appealing.

Will adjust and retry later in the week with the battery on when Utah warms back up a bit. It's been approximate to freezing lately, and cold tires + cold suspension would bias the NVH evaluation a lot. Should be in the upper 40's, low 60's soon.

In addition to the added swingarm length, i could get a swingarm designed so that it allows me to fit a 22" in the rear. A 18 x 2.25" moped tire would be a dream come true.

Would going even more tall than this deteriorate handling significantly? I'm kinda wondering if having a slightly longer wheelbase would make up for that deterioration but IDK.
 
neptronix said:
How good are you at doing this on a scale of 1 to 10?
Click to expand...
Probably less than 5 TBH. Good enough that I've MIG welded several critical components (both steel and aluminium) back together on my own bike's/scooters and so far they've held up, but bad enough that I've had to subsequently re-weld at least 2 of them again, and unsure enough that I don't often let close family members ride on them if I can avoid it.

That being said, I've only been welding for about 18 months and getting better all the time. Next on the list is a catapult for a family member, followed by a go-cart they intend to ride in.

Anyway, all that being said, I don't seriously think it would be worth it for the cost of shipping it out to me and back. Realistically you'll find someone stateside that can do it better for less....just keep looking!

Cheers
 
Less than a 5? keep practicing. No offense intended; i'm looking for expert work i could trust my life on and i'm game to pay for it.

I expect a good quality enhanced replica swingarm made of chromoly or aluminum to cost me $1000 USD-ish. Wondering if this seems like a realistic estimate for a small time builder?
 
neptronix said:
Less than a 5? keep practicing. No offense intended; i'm looking for expert work i could trust my life on and i'm game to pay for it.

I expect a good quality enhanced replica swingarm made of chromoly or aluminum to cost me $1000 USD-ish. Wondering if this seems like a realistic estimate for a small time builder?
Click to expand...
Fair enough! Honestly the cost to send it to Aus and back would exceed 1000USD anyway, so not worth it.

Here is my latest weld repair to the swing-arm on my AT in mild steel. Its held up without issue for a few thousand kms so far. I'm happy.

I also welded the seat on this bike in Aluminium. Was my first go at Al, and it's held up even longer.

I basically substitute my lake of skill with copious amounts of weld...as I get better I should need less weld. :p

Cheers
 

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Hey not bad!


Saltair guy hasn't responded to me after 2 calls and 1 email so far.
PaPaSteve recommends i talk to Maxarya about custom fabrication first, otherwise he'll take on the swingarm job even though it's difficult.


It hit 47F today and the sun was out. I had to test.
Judder factor ( 1-10 scale of vibration, where 5 is too annoying ) since last run: 4.5

Put the battery on the front, tire at 30PSI, moved the seat angle to position 1, moved the battery as forward as it would go.
Judder factor now 4.25. Way smaller difference than expected.

Took 5 PSI out of the front tire, judder factor now 3.75 ( tolerable ), but front tire starting to get a bit wobbly ( super narrow front rim is not helping )

Of course this 'puncture proof' Schwalbe is immediately flat 1 hour after the 4 mile ride from a goathead. Unlike the Kenda Cargo, which i've seen a few dozen leftover spines on 2 bikes but no punctures thus far.
Honestly i should have sent that tire back after feeling how flimsy it was.

I'm broke this month but here's my to-order list for next month when i have a few bucks:
- Sunlite UtiliT 20 x 3.0" for rear
- ??? 20 x 2.25" very flimsy BMX or kids mountain tire for front
- Another Tannus Armor for front
- Much wider front wheel
- This suspension fork
 
Last edited:
neptronix said:
Put the battery on the front, tire at 30PSI, moved the seat angle to position 1, moved the battery as forward as it would go.
Judder factor now 4.25. Way smaller difference than expected.
Click to expand...
Not surprised. The lack of effective fork/shock 'damping' appears to be the main culprit. Adding sprung mass can alter its amplitude & frequency, but I would not expect it to completely suppress jutter. Tire selection (composition) and inflation pressure will also affect the 'jutter', so I'd suggest you take detailed notes. Only change one item at a time between testing.

Most bicycles were never designed for speeds much higher then 15-18 MPH, so when you exceed those speeds, the dynamics change. How many motorcycles have you witnessed without shock absorbers?
 
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When trying to improve the weight balance small changes to the heavy end yields the most results.
Adding more length to the swingarm will definitely help the balance a lot.
Balancing the wheel(s) should be part of the judder investigation.
Wheel balance should always be considered as part of vehicle prep.
Bicycle wheels can sometimes require a little more creativity in balance stand set up verse a motorcycle wheel such as removing seals so the wheel spins with minimum friction.
Back when commuting on motorcycles in the Bay Area California, where it's legal to lane split, the Botz dots between lanes would upset the suspension.
The motorcycle suspension was fully adjustable.
To understand the issue I used the phone gyro and a data app.
Phone needs to be mounted firmly to gather the data without any noise.
You may need to mount the phone in a couple different places to see the issue fully.
I learned the phone gyro trick tracking down vibration and noise problems on machine tools.
Modern phone is such an amazing tool !
 
Saltair dude says:
"These days I stay busy enough with custom frames, so I'm not currently taking on modifications or repairs of other peoples bikes."

PaPaSteve, i'll post up some pictures of the roads on my 4 mile test course later. It has every possible permutation of crappy mountain road problems, including a gravel section.

Today i took off the schwalbe tire and found a V shaped cut in the tube, the tire wasn't punctured at all. There is also a cut in the tire liner around where the tube was damaged. There is also an I shaped dent in the rim in this area. Honestly, i have no idea how this occurred.

I also find that i don't like riding in the upright position at all. The handling becomes more uncertain. Moving back to mid-tilt doesn't seem to affect the judder problem all that much. The 10.5lbs battery is doing the real work!
 
neptronix said:
Today i took off the schwalbe tire and found a V shaped cut in the tube, the tire wasn't punctured at all. There is also a cut in the tire liner around where the tube was damaged.
Click to expand...
Possible installer error? I personally admit several own-goals from sloppy use of tire levers. :rolleyes:
 
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