Full-Suspension Longtail 2.0

spinningmagnets

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The start of this bike can be found here: http://endless-sphere.com/forums/viewtopic.php?f=3&t=18157

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I wanted a bike that was slightly longer and lower, but had full suspension front and rear. I wondered why few had put a rear-sus arm from an MTB onto a hardtail MTB by bolting the pedal-axle (Bottom-Bracket, BB) into the drop-outs. I tried it, and I like the result.

My feet are now flat on the ground, the seating position is slightly more semi-recumbent (like a beach cruiser, rather than leaning forward like a road bike) and the combination of fat tires and FS make the bike handle rough sidewalks and potholes in the street very well.

The oiriginal seat and shock-absorber mounts were made fast and ugly. Once I determined that I liked it, that there were no major issues when configured this way, and I also located the position where I most liked the seat, I began pondering a more permanent arrangement of parts.

FSLB2.0ShockMount.JPG

I wanted to open up the rear frame space for some type of non-hub motor with a Left-Side-Drive (LSD), but, that is at least a month away (or more). The mods so far have been accomplished with a vice, hacksaw, drill, and files.

The seat-post will be a fork (possibly from a 12" childs bike), to allow the shock to pass through. The seat-post mount shown is a copper plumbing-T with a brass seat from a kitchen faucet (part# 0296, "American Standard" brand). The outside diameter of the cylindrical brass valve seat was 0.875". The holes in it were there from the factory (all holes approx 0.33")

In Plumbing terms, the port that the brass valve-seat was able to slide into is called a standard ___ copper-tubing size. The main 2 ports were 1.0" because my frame has one-inch diameter tubing there (other diameters are available). Though, I did cut half of its diameter away so I could pop it on from the side, and then clamp it down with two stainless steel hose-clamps.

I like the way the copper looks, but if you want to save a few dollars, use a cast plumbing T (brass or iron), and a section of plumbing pipe with threaded ends. Cut the pipe in half, thread one of the stubs into the center of the T, smash the pipe stub flat, and drill a hole.

Once you locate where you want the frame additions, a more professional-looking arrangement (that is still affordable) would be to cut out some joints from another frame to make lugs. Then braze them onto your frame with a MAPP-torch (of course, study first and practice on junk). The lugs in the pic below are curved so stress is spread out (its not just for decoration)

lugs10135011.jpg


If your frame tubing is not round, perhaps rub a waxy lip balm onto the frame, and fill the void with JB-Weld metal-epoxy (which will adhere to the inside of the fitting). Once dry, cut and file away the excess, then clamp it down. This will spread out the clamping loads, so you can get a good grip without crimping the frame tubing. The epoxy forms a perfect fit to oddly-shaped tubing, and the wax prevents it from sticking to the frame.

Also, if using U-bolts as a clamp (as I did on the shock mount), you might consider making a clamping saddle from a section of steel pipe that has been cut lengthwise. If anyone doesnt like this plan, just wait 20 minutes, it will change.
 
One note on the copper is that if it has any flexing at all, it will probably eventually work-harden, and crack. So keep an eye on it for that, so you don't end up sitting on the road or the shock all of a sudden. ;)
 
Thanks for the heads-up AW, I'll keep an eye on that. Part of the reason for using a clamped-on seat mount is that I am still not certain what I'll be doing for a non-hub motor-drive, and I wanted to be able to easily move the seat-mount if needed.

While waiting for my house to sell, I am working at a good job in another state, and renting a room from a friend and co-worker (no garage). My previous sympathies for apartment/dorm dwellers was theoretical, but now...my sympathies are very real.

Though I own a stick-welder (in another state!) my welding looks like bird-droppings. I hope to improve that in the near future, but now I am much more interested in MAPP-gas torch brazing, and also what is possible just using propane. Though steel continues to be the best choice for specific applications, I am enjoying working with aluminum, and it seems a brazing kit could be fairly compact and reasonably affordable.
 
The seat support is stronger than it looks, and its main function is to hold up my fat ass while I decide what to do to the rest of the bike. Since I'm still not sure about exactly how I will want it to end up (need to test ride and adjust), this odd seat mount remains moveable, adjustable, and easily removeable (not welded/brazed)

FSLBjuly.JPG

This handlebar arrangement allowed me to find where my hands are most comfortable. However, before Big-Poppi Bikes made me an extra-long derailleur cable (Thanks, Aaron and Jeff!), I was stuck in one gear, and this handlebar makes it awkward to stand and pedal. I now believe this is why beach cruisers have a normal forward-facing quill-stem and long sweeping handlebars. The long sweep back allows semi-recumbent seating, and the air-space in the middle leaves lots of room for your knees if you stand to pedal.

When looking for tubing to use as a sleeve/shim/spacer, the diameter only needs to be close. The wall thickness is the critical dimension, and you can see the brass pipe (bottom left) and soft-steel conduit I used (where the handle connects to the BMX handlebar) with the appropriate wall thicknesses to make a solid clamping to the adaptations. The handlegrips came from thrift-store crutches that I bought for the aluminum tubing ($5/pair, look for the extra-tall adult size). I considered them to be temporary, but now I really like them. They have a central "ball" shape to them that is very comfortable.


Needed a longer kickstand, found a hollow one "in the pile" and cut it half on faith. My trusty 4" caliper showed the diameter and wall-thickness would allow a 1/2"-13 tap to cut threads, and my pile of junk supplied an all-thread stub with two jamb-nuts. I have changed the length several times with various modifications to the bike. Being adjustable was handy, and the new $5 tap will not go to waste.


This is a 10-inch diameter skillet...you know...for those cooking emergencies that sometimes come up on the road?
FSLBskillet.JPG
 
Shall we stir up some Kentucky-Fried Lipo? :lol: (oddly it kinda looks about the same size as a 9c....)

I really like the handlebar-stem bar-ends/grips. :) I'd never thought of that; would be useful for a number of things besides just grips.

If you leave the whole stem bolt out, with just the pointy wedge end directly forward, you can use it to clear a path when riding on sidewalks. :lol:

You might also look for the beach cruiser bars and turn them nearly vertical, as I did with CrazyBike2 (and will again with the newer version in progress). Grips aren't vertical like yours, though, but rather angled outward some instead. (I would like to bend mine inward a few degrees, but am afraid I'll screw up the bars doing it or find it is too far in and be unable to rebend them outward).
 
The odd shock mount was made to show that it was "possible" without a welder or brazing torch. Now, I would actually recommend cutting steel pieces with a hacksaw (or an electric sawzall if you have access to one), filing to fit, and finding a friend to weld the pieces together for a $20. If you are lacking a friend with a welder, most car muffler shops will do small odd piece welding. Add some primer/paint and it would look more mainstream.

I like it a lot, but...even with welded pieces that would be more professional-looking, I don't think this is for everyone. If you are comfortable being seen in public on a recumbent (especially with a partial fairing) then you might be the kind of guy who would appreciate the benefits.

Fat tires and full suspension soak up the potholes (there are many here). On some streets, cars force me onto the sidewalk, which are just as bad as my streets. My back is comfortable with an upright posture (I'm old). I like how my feet are flat on the ground when I come to a stop.

Teen MTB's with 24-inch wheels are easy to find very cheap on Craigslist. Once stretched by mating two frames it would be long enough for an adult. They practically give away hundreds of cheap China-Mart 24-inch / 26-inch MTBs at colleges immediately after graduation.

Its not expensive.

Although...I think I will be getting some "sweep back" beach cruiser handlebars and reverse the bar clamp back into the normal position.
 
It's a Bob-Job! The right headlight and a bobbed rear fender...... don't stop now: I like it. Nice ride!
 
Thanks! here's a pic of Dogmans longtail, also made by mating two near-free frames. Dogman sliced the head tube from the rear frame ( a common "Y" shaped MTB), and left the front and rear mounts for the shock absorber in the stock configuration. His method is much easier, and If I was going to make another FS longtail, I would definitely copy his build.

I used to like the BMX handlebars with the reversed stem (that configuration allowed an upright posture with my arms holding level, instead of leaned down). Now I recommend the common beach-cruiser bars that sweep back. That way when you stand up to pedal (on rare occasions), your knees won't brush up against the handlebars. Just a personal preference...

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Frame detail pic added per cyclebutts curiosity in a post below.

DogmanLongtail.jpg

From Lemlux http://endless-sphere.com/forums/viewtopic.php?f=6&t=42103#p693345
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The main problem with long pullback cruiser bars is that they often slip in the stem when you apply force to them (like when rising out of a really laid-back seat to stand and pedal). The bar I prefer for shifting the grips rearward while maintaining knee clearance is the Wald #867:

3239930932_36208dcf74_z.jpg


It still might need a reversed stem, if you require a metric buttload of pullback, but it's much less likely to slip than most cruiser bars. It's widely available, still made in USA, and cheap as dirt.
 
That looks a lot like the ones I use on CrazyBike2 (and now on my Delta Tripper trike); I don't know if theyr'e exactly the same though. Even so, I have had that problem of the bars pivoting in the stem a few times. Thought about adding extra grooves on the bars and in the stem clamp, never did it. I just try not to push that hard on them, and I use the center part of the bar to push/pull myself up from the bike and lean on to sit down, rather than the lever of the bar grips.

But I mount mine higher up in front of me, and angle the bars downward, so it's more like holding a steering wheel, because of my seating position.
 
spinningmagnets said:
Thanks! here's a pic of Dogmans longtail, also made by mating two near-free frames. Dogman sliced the head tube from the rear frame ( a common "Y" shaped MTB), and left the front and rear mounts for the shock absorber in the stock configuration. His method is much easier, and If I was going to make another FS longtail, I would definitely copy his build.

I used to like the BMX handlebars with the reversed stem (that configuration allowed an upright posture with my arms holding level, instead of leaned down). Now I recommend the common beach-cruiser bars that sweep back. That way when you stand up to pedal (on rare occasions), your knees won't brush up against the handlebars. Just a personal preference...

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I sort of follow what you said about dogman's build. Do you have, or is there a link to that build. I'd like to see photos of the bare frame connections. These bikes are way cool.
 
http://www.endless-sphere.com/forums/search.php?keywords=longtail&terms=all&author=dogman&sc=1&sf=titleonly&sk=t&sd=d&sr=topics&st=0&ch=300&t=0&submit=Search
 
amberwolf said:
http://www.endless-sphere.com/forums/search.php?keywords=longtail&terms=all&author=dogman&sc=1&sf=titleonly&sk=t&sd=d&sr=topics&st=0&ch=300&t=0&submit=Search
Thanks, amberwolf,
These are GREAT DIY cargo bikes. The only problem I can see is finding the time to build one! So many projects...
 
Great project, I like the idea to make longer wheelbase without using a welder, especially when using an alloy frame. I will stick to an elongated swing arm, but I still like your concept for a cargo bike. Thx for showing us what possible!
 
Chalo said:
The main problem with long pullback cruiser bars is that they often slip in the stem when you apply force to them (like when rising out of a really laid-back seat to stand and pedal). The bar I prefer for shifting the grips rearward while maintaining knee clearance is the Wald #867:

3239930932_36208dcf74_z.jpg


It still might need a reversed stem, if you require a metric buttload of pullback, but it's much less likely to slip than most cruiser bars. It's widely available, still made in USA, and cheap as dirt.

I bought one of these based on your recommendation. This bar slips in every stem i have. The diameter of the part that hooks on to the stem is just slightly smaller than every other bar i own ( i have 10 laying around ). It's a nice bar but it is doing the opposite of what you mentioned :p
 
Nep, you may need to buy or make a tube-shim. It doesn't have to start out exactly precise for the ID, just close to a workable wall thickness or slightly thicker. Find a short brass tube (plumbing section of the hardware store), and spin it with a drill while holding coarse sandpaper up to it, until the OD reaches a diameter where you know the wall-thickness is good. Then cut to length, and then cut at least one lengthwise split (or maybe two as shown in the pic) When you tighten down the stem clamp, it will compress the shim into the proper shape.

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neptronix said:
Chalo said:
The main problem with long pullback cruiser bars is that they often slip in the stem when you apply force to them (like when rising out of a really laid-back seat to stand and pedal). The bar I prefer for shifting the grips rearward while maintaining knee clearance is the Wald #867:

3239930932_36208dcf74_z.jpg


It still might need a reversed stem, if you require a metric buttload of pullback, but it's much less likely to slip than most cruiser bars. It's widely available, still made in USA, and cheap as dirt.

I bought one of these based on your recommendation. This bar slips in every stem i have. The diameter of the part that hooks on to the stem is just slightly smaller than every other bar i own ( i have 10 laying around ). It's a nice bar but it is doing the opposite of what you mentioned :p

That's not good. We don't have that problem on my shop's rental cruisers, all of which have had their bars replaced with Wald #867 bars. The advantage of the Wald #867 compared to pullback cruiser bars is a shorter lever arm between grips and stem clamp.

Maybe a shim from softer metal would help the stem grip it. .010" Aluminum flashing adds 0.5mm of diameter to the bar if you wrap it all the way around, and allows the bar's knurling and any asperities on the stem to bite in. Copper flashing would work about the same way. At my shop, we use the material from 24 ounce beer cans to do the same job when the diameter is close, because it's about half as thick as flashing.

Also make sure that the bolt or bolts clamping the stem onto the bars are greased, both the threads and the underside of the head. That yields the most clamping force for a given tool torque.
 
Spinningmagnets - How do you like the rider positioning?

I am working out space beneath the seat on my trike for controller and batteries, and optimizing for pulling a trailer...

I do want to generate some pedal power (which I know is compromised) from a stand-up position, and I am also considering a bit of a lower back support for longer rides. What do you think?
 
The longtail is still dis-assembled from the recent move to another house. I love the full suspension with fat tires, and the semi-recumbent posture having an upright back. When at a stop, both of my feet are flat on the ground.

The benefit of the conventional race-bike posture (vertical legs and leaned-forward torso) is that there is less wind resistance, and also on slow climbs, you can sway your body from side to side to apply force to the pedals. On a recumbent/semi-recumbent, you cannot move your body weight from side-to-side (very efficient way to apply force to uphill pedals)...any hill climbing you do is all leg muscle.

The BMX bars on a reversed stem worked fine, but on rare occasions I actually wanted to stand on the pedals to change my posture for a minute. Thats when I noticed that my knees would brush against the handlebars, and it annoyed me. I realized that this was the reason for the classic single-speed "beach cruiser" handlebars. The longer sweepback allows the majority of your riding to be upright on flat land, but when standing to accelerate, the forward stem and straight front section of the handlebars provide a space for your knees when standing on the pedals. I plan to get a set of these bars that Chalo recommended, but I am swamped at the moment with three projects that are consuming me.

Plus, women are funny...you marry them, and then they want you to spend time with them...
 
Sorry for the Mother's Day intrusion. I was giving my wife the one thing all women seem to love...uninterrupted sleep.

I have only ever really tried one position...maybe it is my midwestern - Bible belt roots...but putting my feet on the ground, leaning back...seems dangerous and socially destructive :wink: .

Actually, I really like it being lower with the trike, I like having my feet able to rest on the ground without needing to worry about the pedals whacking my shins, I like being able to lean back with some back support,...but I worried about my upper back getting tired from stretching forward for the handlebars...and as the sage Chalo spoke of...I was having trouble with the reversed stem allowing the handlebars to rotate.

I am making some modifications to the handlebars and I plan on attaching a support from the stem mounting bolt? to a point midway up the handlebar, which should prevent this movement, and allow for a small lexan? fairing and dashboard attachment adding extra protection for my electronics.
 
If its any consolation, I've never liked something so much before...that my wife hates this much. She wants to blend in and look normal, and I only care about performance. The ride is so comfortable and my feet are flat on the ground at a stop. If my wife didn't hate it so much, I'd make a new one that was prettier, or at least more professional looking.

here's a pic of the two types of cheap "Walmart" style full-sus swingarms. Both are steel, and the one on the right has an integrated stud that is threaded. I recommend getting the style on the left which has a threaded hole. This provides the opportunity to get a bolt of any length necessary, and also you can cheaply acquire a VERY strong high-grade bolt, istead of the cheap soft steel found on the example on the right.

2015-03-11 10.08.51.jpg
 
Yup.... mines crazy short tail and looks silly.. but wheels in and out of places easy... yay for re-purposed full suspension bikes...
 
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