Terra Trike Tour 2 - budget performance conversion.

[Comrade]

Don't like is they don't fit tight enough

If you can measure your axle next time you do maintenance I would appreciate having another data point. With 0.01mm resolution calipers if you have them. And I'll compare to my motor when I get it. I'll probably make some custom laser cut torque arms over the winter, but I wonder how universal they might be if axles are not very tight tolerances.

 

[ZeroEm]

That is what i'm saying, this stuff we buy is not in tolerances. It varey's from production runs. Don't blame Grin they know all axels are not the same. That is why make them to tight then open them up until it is a force fit.

Have a motor not mounted yet. That can be measured, the one on my trike has not been off in three years. Getting a little rust around the spoke holes and needs to be refilled with FF. Plan on taking it off when I swap motors. Then I will upgrade my wires and change out my thermistor. What every else it will need. Then will put it back on. Need to buy another spare, thinking about a 6T leafmotor, then drop my battery voltage into the 60's.

Don't need to work on my bikes much, spend time to get it right then just use them.

y Comrade » Oct 29 2021 9:05pm

ZeroEm wrote: ↑Oct 29 2021 6:35pm
Don't like is they don't fit tight enough

If you can measure your axle next time you do maintenance I would appreciate having another data point. With 0.01mm resolution calipers if you have them. And I'll compare to my motor when I get it. I'll probably make some custom laser cut torque arms over the winter, but I wonder how universal they might be if axles are not very tight tolerances.

 

[HackD]

Yes and I like it. Gives me ideas. Ride a performer Trike, the front end unbolts. Once you get it figured out then I just need to make something that bolts on the trike to bolt your Arms and shock to. Then there will be a suspension kit for Performer trikes.

Well, looks like my Project OCD kicked in a bit, and went into overdrive in looking at parts/sourcing options. Obviously, the good start point would be sourcing the base wheelset, and moving forwards. Paired with some tabbed head-tubes - that's the basis of designing from there. Initially, i thought i'd be building a set of wheels - but the issue of spindle/brake mount assembly to fabricate was concerning. I thought getting a complete wheelset assembly was out of question - one source i found on Aliexpress had very limited shipping options, not including Canada. Personal Contact, got that sorted, so they'll be inbound within a week or so.

I can fit as least 2.15 tires on these .. if not good enough, i'll replace the rims with wider, down the road, so to speak.



About your idea in terms of convertibility - i am, in my ideas, thinking of building this up in modules. ie the front suspension is a standalone sub-assembly, bolted to rear main battery tray/seat mount, etc... Once i get my specs down on paper/sketchup/autocad whatever. I'm not doing this with any illusions of mass producing - but it would fall in line with design elements/functions i wish to incorporate into my own Frankenstein build. That could include a Stein bikes' style basic suspension setup, but some things could be done with more unconventional methods as seen in some DIY Adaptive Trikes, in terms of no-weld/infinite adjustability aspects and modularity, in a land-mine proof chassis.

 

[HackD]

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These torque arms sell for $42.50 each on Amazon and you got one for each side. That's big cash money ballin!

I was thinking of drawing a bracket that would do the same but look much prettier in CAD and having it laser cut from some stainless steel. There are custom cutting places online that should make a dozen brackets for the price of a pair of Grins.

ZeroEm, what was your solution for torque arms?

I blame the Ballin' on my OCD for design/setup Symmetry!

I don't think i paid Golden Motors/Grin Tech that much for them, when i bought the hub kit.. but they weren't cheap, either. They also served double-duty (after the fact) of serving as very substantial mounting Tabs, for the heavy duty rack/top box combo bracketry that i put on it a little later - so was definitely worth it in the end.

I suppose the use of my term 'budget performance' is somewhat misleading, if not outright laughable when it comes to using higher dollar parts like that.. I certainly didn't cheap out on this project.. i'll never cheap out on Safety items - and when in doubt, build it stout! .

I'll have my Retirement to regret it later, i am sure, LOL!

 

[HackD]

Free Post, with Video link of last good weather ride in these parts.

I'm now actively moving into planning out a new build and squirreling parts away, so unsure if will document on this thread, or make new thread. In interests of keeping my projects separate, best i guess to start new. This won't be necessarily finished any time soon - as i have another main project on the front burner this winter, already.

Stay tuned..

https://youtu.be/U0f7RDf8jCM?t=239

 

[ZeroEm]

Good video like to see where the riding occurs.

 

[HackD]

Good video like to see where the riding occurs.

That's the sort of Ravine/Trail/Escarpment environment that i enjoy - but that includes rougher trails, and mixed surface paths.
Although often double track, the secondary trails are often also rock/root rutted off the main trail AND making elevation changes. As can be seen in that video, the ~10% grades on the main trail entering into the Valley are cobbled/paving stone surfaced. I call that, the shake-test to see if anything drops off, before i get too deep into the Valley..

an eTrike with a proper suspension setup, would totally shine in that environment. It would also be able to handle the rougher trails down to the shale surface environment, immediately adjacent to the creek.

 

[HackD]

Finally got around to finishing off one aspect of the SWB Terratrike - overall Stability/Sensitivity of the front end, which definitely gets twitchy with a dangerous tendency to oversteer and possibly have a CofG shift induced roll-over, if it gets too loose, at too high a speed on steep downhill grades... steering stabilizing damper. I actually picked it up last Fall, but needed time for the mounting solution to marinate in my mind.

Low and behold, my previous lighting mount method, works perfectly, to add a 3/16"s custom bracket, in order to mount the steering damper to it. Appropriate sized spacers as stand-offs with 8mm bolts of appropriate length, got the geometry of the damper perfect, while closely conforming to the bottom of the trike.

A couple of evenings spent punching out the rough pattern of my mount with drill-press, a lot of filing to make an aesthetically pleasing mount, a couple spacers and 8mm bolts out of the spares bucket, and Bob's yer Uncle.

Just took it for a test run down my favorite steep slope.. works as desired, steering is much more confident, less over-sensitive for that specific environment, with the damper dialed up.

 

[ccihon]

nearly 20 years ago I had a TerraTryke, "3.2" I think it was. The lack of high speed stability led me to do the same motorcycle steering damper thing you have done here. I felt like on that (non-motorized) trike, it helped but only marginally.

My current trike, still an older model, is direct steer, and was always very stable at speed. Interestingly, I did add a steering damper to it, not for the high speed stability, but because at lower speeds and over rough roads, the steering would develop a "shimmy" or oscillation - this because I also added a mid-drive motor on the boom and the weight shift forward was causing the oscillation. For this purpose, the damper entirely cured the problem. I had to mount it a bit strangely as the steering geometry is different than a TT, and the damper is not parallel with the cross bar or tie rod etc - works perfectly. I found an aluminum ring designed for motorcycle mounting of these things that was the same size I needed for my frame.

Pics on this post: https://endless-sphere.com/forums/viewtopic.php?f=3&t=112937&start=25#p1676243

 

[HackD]

nearly 20 years ago I had a TerraTryke, "3.2" I think it was. The lack of high speed stability led me to do the same motorcycle steering damper thing you have done here. I felt like on that (non-motorized) trike, it helped but only marginally.

My current trike, still an older model, is direct steer, and was always very stable at speed. Interestingly, I did add a steering damper to it, not for the high speed stability, but because at lower speeds and over rough roads, the steering would develop a "shimmy" or oscillation - this because I also added a mid-drive motor on the boom and the weight shift forward was causing the oscillation. For this purpose, the damper entirely cured the problem. I had to mount it a bit strangely as the steering geometry is different than a TT, and the damper is not parallel with the cross bar or tie rod etc - works perfectly. I found an aluminum ring designed for motorcycle mounting of these things that was the same size I needed for my frame.

Pics on this post: https://endless-sphere.com/forums/viewtopic.php?f=3&t=112937&start=25#p1676243

It's very much velocity contingent, based on a downslope bias. As you put it, it's potentially Oscillation inducing with oversteer.

Anything under 30km/h / 20mph - entirely manageable. It gets dicey above that. Routinely reaching 50km/h in those optimal gravity-hill conditions, i want steering stability, 101%.

I've got a bunch of those motorcycle damper mounts on hand - i bought them for an unrelated project (to this one). Just wouldn't work to my satisfaction, for this application.

 

[ccihon]

The TTs were ofter called "terror trikes" as they started to feel twitchy at high speeds - I know it scared me enough to add the damper. I think or hope most trikes these days have avoided the steering geometry problems that contribute to this. Subtle differences in kingpin angles can cause big changes here - camber, track, and trail angles. Trade off for stability for these older ones may have been that they were trying to reduce tire scrub and wear - not certain.

My current trike even without the damper is dead steady at speedy downhills and the damper was only needed to prevent bumps at low speeds causing a wobble - I found this could also be cured by running the tires under-inflated, but didn't like that as a solution.

https://www.kevinatkins.org/terratrike/chuck/index.html

There are still some pictures up from the most recent turn of the century showing my old TT - here I used a steel collar clamp for the static frame mount, and drilled and tapped. Seems like back then I couldn't find anything exactly off the shelf there.

It's interesting to see this older trike - still had drum brakes (they worked quite well), and show the early manufacturing choices of what was at that a very small company - note the stack of steel washers they used as a spacer in the steering arm area. I recall I had the Schlumpf drive with a double ring up front. 20" wheels all around were actually a nice choice. I feel like the 559 I have on the rear now induces more frame twist and causes some chain skipping on the biggest rear cog when pedalling and cornering at the same time.

 

[HackD]

The TTs were ofter called "terror trikes" as they started to feel twitchy at high speeds - I know it scared me enough to add the damper. I think or hope most trikes these days have avoided the steering geometry problems that contribute to this. Subtle differences in kingpin angles can cause big changes here - camber, track, and trail angles. Trade off for stability for these older ones may have been that they were trying to reduce tire scrub and wear - not certain.

My current trike even without the damper is dead steady at speedy downhills and the damper was only needed to prevent bumps at low speeds causing a wobble - I found this could also be cured by running the tires under-inflated, but didn't like that as a solution.

https://www.kevinatkins.org/terratrike/chuck/index.html

There are still some pictures up from the most recent turn of the century showing my old TT - here I used a steel collar clamp for the static frame mount, and drilled and tapped. Seems like back then I couldn't find anything exactly off the shelf there.

It's interesting to see this older trike - still had drum brakes (they worked quite well), and show the early manufacturing choices of what was at that a very small company - note the stack of steel washers they used as a spacer in the steering arm area. I recall I had the Schlumpf drive with a double ring up front. 20" wheels all around were actually a nice choice. I feel like the 559 I have on the rear now induces more frame twist and causes some chain skipping on the biggest rear cog when pedalling and cornering at the same time.

"Terror Trikes" ... interesting. I'm a rank noob when it comes to Tadpole trike Geometry, but i've got experience with Sidecar rigs - a mix of Theoretical methodology and invocation of Dark Arts in setting those up, so they aren't 'Terror Trikes'...

I assumed that the sketchy handling at higher velocities than intended, was part of the nature of the SWB aspect of the TerraTrike - between that, and myself asking way much more of it, than was originally designed for, which is a ~20 km/h budget priced pathway Trike for 'Retirement Land', for the average user, so to speak. It would be interesting to pick up a set of drop-out extensions (or fabricate up a set if able - they've been long discontinued) to experiment with overall stability/lengthening wheelbase, and it's effect on handling/CofG.

Frame Twist? I'll tell ya about frame twist, with that Cast rear hub boat-anchor back there, with a 2.4 skin on it. I need to keep an eye on the frame in that location - because that will be a potential point of failure at the convergence of main frame tube and drop-outs.

In any case, given the inherent design limitations of the base TerraTrike, with a few more rides in to test it, it appears that i've now got it optimized as much as reasonable possible, at this point - with this final change. Yay.