Sun ez tadpole engine kit help

Like this 'un?



If so - then yea, a rack mount is prolly the easiest way to go, but there's no need for a friction drive, there's a buncha options for chain or belt drive rack systems in both two and four strokes, also many come complete with the rack & mount... I don't think there'd even be much if any modification/fabrication should ya choose that route...

I gotta say that although two strokes have better power-to-weight and tend to be less expensive - with the motor right behind yer head like that ya might wanna consider the slightly quieter four stroke

BA if a Dax Titan setup is used, it would put the motor right at your head. I can see brackets that set the motor behind the bike. Would not be that hard.

....or even a push trailer and retain the trike in original build shape,and then you can switch trailers if you do an elect.one too

bigalan said:

I want to put an engine kit on my SUN EZ3 TADPOLE

Has anyone done one of these yet?

What type of kits will work?

4-stroke or 2-stroke

Maybe a friction drive on rear wheel , I would have to make a custom bracket for the friction drive unit.

Any help as I would like to do this right 1-time and have a nice lowrider cruiser.
Thanx for any help

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Here is picture of a setup that could work. You will have to do some research to figure out what kind of motor it is. It was something I liked the looks of and saved the picture.

A few things about Sun Tads

If you go looking for a used frame here's a few things to remember - 1. The yellow frame Tads did not have a cruciform brace, so cracks in the weld where the wheel tube and main frame tube join are common (a good welder (not a shadetree welder) could fabricate one for you), 2. the first version of the red/black frame did not have the brace either, but the second version did, 3. A good welder can fabricate a larger fork for you that will allow you to use a 24" or 26" rear wheel (think a very heavy version of a Catrike Expedition) thus using Golden Eagle engine and spoke mounted pulley with their toothed belt, 4. AND THIS ONE APPLIES TO ALL MOTORIZED BIKES, replace the stock brakes with top line hydraulic disk brakes!!!!! Rim brakes and cheap cable disk brakes compromise stopping power. The cheap (even Avid 5's) disks just aren't up to the task of stopping you at higher speeds and heavier loads, and finally - 5. Never try 'Flintstone' brakes on a tadpole or delta trike. Flintstones lead to "leg suck" - one or both legs being sucked under the trike leading to broken bones, torn tendons in ankles, knees and hips, faceplant into the chainrings and HEAVY AND PAINFUL contact between the frame tube and your 'package'! And yes, this can all happen to the young and 'indestructable'.

funny the first cars/trucks had mechanical brakes and stopped just fine


most guys on here with V brakes that are set up right also stop just fine
hydro disks are something that beyond overkill

It's interesting this is posted in taddys as after all, they do have an "extra" brake over bicycles & thus, greater stopping power

TBH over time I've developed a bit of a serious dislike for V brakes - it's isn't that they're cable actuated, wear rate, or even stopping distance as cables work jus' fine & are very easy to maintain w/simple roadside repair, longevity is drastically improved with just some quality pads, as is stopping distance...

The problems I have with them is drag & weather conditions. Yes, a properly adjusted set of V brakes shouldn't have this problem - but no matter the care, maintenance & attention paid it seems at least one of 'em is always rubbing the rim and irritating the heck outa me & honestly? No matter the quality of the pad they don't work that well in the rain & forget about it when they load up with ice in the winter.

Drum brakes ofc are less susceptible to these issues - but they do suffer "fade" wen they heat up under hard use. They're even worse than V brakes when wet - but you'd hafta submerse the hub to get them wet, so it's kinda a moot point.

Quality disk brakes are in my opinion the way to go & by quality I don't mean thousands of dollars, jus' not the cheapos that come stock on box store bikes as often the inner pad isn't adjustable in any way and drags/squeaks - but even the base model Avid BB5 calipers are really good (adj knob for one pad, cable adj for the other), ofc with a mount ext you can increase rotor size for improved stopping & cooling.

In my opinion, while hydraulics are nice, with slightly better sensitivity & pressure - I just don't see them as worth the bother and expense for such marginal improvements and problematic roadside repair... anyone who's had air/leaks in their car's brake lines knows what I'm talking about lol

Yes, hydraulics are awesome - but don't not get disk brakes 'cause hydraulics are spendy, (quality) cable systems are great

Ibedayank said:

funny the first cars/trucks had mechanical brakes and stopped just fine


most guys on here with V brakes that are set up right also stop just fine
hydro disks are something that beyond overkill

Click to expand...

The first cars/trucks weighed a fraction of what modern cars/trucks weigh and traveled at a fraction of the speed that modern cars/trucks do. Also, the traffic competing for the same space was a fraction of todays. Just too many soccer mommys and A-type daddys that just have to be somewhere first and don't much care if you are in " their way". As soon as hydraulic brakes (and later vacuum assisted hydraulic brakes) were invented, mechanical brakes were dropped from use. But, better brakes required better tires to utilize the increased stopping power. Compare the tires on todays F1 or Indy cars to those on the cars of 40 years ago.

V brakes were a great advancement over center pulls, just as center pulls were a great advancement over side pulls. And there is always the issue of parasitic drag that comes into play when talking about disk brakes. But drag is less an issue to a motorized bike than to the non motorized rider. The "experts" say an average rider can maintain 1/10 hp over an hour, a top roadie maybe can maintain 2/10 - 3/10ths hp over an hour - on a bike that weighs maybe 15#. My USX trike bare weighs 65#, add in 35# of motor/trans plus fairing plus my fat a** and we are talking well over 400#, and being over 63 y.o., I'm sh*ts and giggles happy to be able to maintain 1/10 hp and will gladly use an ice to more than make up the difference in power. But that 400# at 25 - 30 mph has inertia that can only be addressed by adequate brakes. BB5's are adequate, BB7's are easier to adjust (in my opinion) and Magura disks with oversized rotors do the job best. Again IMO.

In the end, you trust your life to the technology you believe in - tempered by what your wallet can afford.

The attached picture is a "Draisine" sometimes called a "bone shaker", the first standard form bicycle. Flintstone brakes all around, top speed - somewhere around walking speed (unless it was one h*ll of a downhill). Major danger during riding - Splinter privatus partus or, on occasion "faceplantus roadappleus.

BarelyAWake said:

It's interesting this is posted in taddys as after all, they do have an "extra" brake over bicycles & thus, greater stopping power

TBH over time I've developed a bit of a serious dislike for V brakes - it's isn't that they're cable actuated, wear rate, or even stopping distance as cables work jus' fine & are very easy to maintain w/simple roadside repair, longevity is drastically improved with just some quality pads, as is stopping distance...

The problems I have with them is drag & weather conditions. Yes, a properly adjusted set of V brakes shouldn't have this problem - but no matter the care, maintenance & attention paid it seems at least one of 'em is always rubbing the rim and irritating the heck outa me & honestly? No matter the quality of the pad they don't work that well in the rain & forget about it when they load up with ice in the winter.

Drum brakes ofc are less susceptible to these issues - but they do suffer "fade" wen they heat up under hard use. They're even worse than V brakes when wet - but you'd hafta submerse the hub to get them wet, so it's kinda a moot point.

Quality disk brakes are in my opinion the way to go & by quality I don't mean thousands of dollars, jus' not the cheapos that come stock on box store bikes as often the inner pad isn't adjustable in any way and drags/squeaks - but even the base model Avid BB5 calipers are really good (adj knob for one pad, cable adj for the other), ofc with a mount ext you can increase rotor size for improved stopping & cooling.

In my opinion, while hydraulics are nice, with slightly better sensitivity & pressure - I just don't see them as worth the bother and expense for such marginal improvements and problematic roadside repair... anyone who's had air/leaks in their car's brake lines knows what I'm talking about lol

Yes, hydraulics are awesome - but don't not get disk brakes 'cause hydraulics are spendy, (quality) cable systems are great

Click to expand...

Most velomobile manufacturers build with drum brakes. I've seen a video of the 2005 Giessen velomobile ride where, at the end of the vid is a screen shot of the onbord GPS, showing a daily distance of 199 km. and a top speed of 95 kph. That's quick in anybody's book. The velomobile looked like a Quest, which is prolly the overall fastest velomobile made.

You are 100% right about lack of maint. issues, and overall fade problems with drums. And right about the cost issues, too. But I just can't see drum or disk fade being a real issue unless you are riding in the mountains. I solved fade problems on my Alfa race car brakes by using silicone brake fluid, which had a very high boiling point and no problems with with water absorbtion. Fade being caused by alcohol-based brake fluid boiling from heat. I picked up my Magura Julies with 8" rotors on closeout from Greenfish (now closed) for around $160 (shipping included) and my HP Velotechnik Scorpion can do a nose stand with my 260# body on it on a clean, dry road. Brake pad hydroplaning is pretty much a non-issue with drilled rotors. The Julies use mineral oil as a fluid, not alcohol based fluid. The Julie's pads wipe the rotor clean rapidly, so wet conditions have never been much of an issue. Never had to bleed brakes or replace the pads - over 8000 miles on them.

But for a lighter ride/rider, I wouldn't hesitate to use a BB7 and a bigger rotor. You'll do just fine and save money, too.

PS, in gritty, wet conditions, Vbrake pads will pick up and hold fine grit, at which point you are using sandpaper brake pads. I have seen first hand wheels using narrow high pressure tires fail due to rim abrasion. I have heard about blowouts occurring due to increased tire pressure caused by friction. Brake fade occurs at a much more gradual rate than rim failure or blowout and is more controllable.