hey guys, first post and I’m a newbie to bike building. I want to build an adult sized gas powered replica (as close as possible) to a radio flyer kids tricycle. I have the gas BBR frame with the build in tank. Two 20 inch rear and putting on a 26 inch front wheel. I need help with what to buy that you don’t see in the photo. Especially when it comes to the gears. The back is a trike conversion 7 speed I bought off eBay.
Trying to build a tricycle
- Thread starter Bobsaget
- Start date
Cool build! What do you want to run for power 2 or 4 stroke? Do you want to be able to use gears with motor like a motorcycle? Or just use gears when peddling or both!
Hey thanks,
I like the sound of a two stroke. And would like to be able to use the gears both with the motor and with the pedals. I stuck this springer fork and 26 inch tire up there. I have about 8 inches from the center of the pedal hole to the ground. I might need more clearance? I guess this fork could be adjusted higher?
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Check out this build kit. https://www.pistonbikes.com/Motorized-Trike-Conversion-Kit-p/mtck.htm
I just finished a Schwinn Mercian. I originally had a 212 for it but figured it overkill and too fast. Went with a 49cc HS with a 5:1 gear box. Chose ratios to keep speeds in the mid 20s as wife will use it.Trikes get squirrly much faster. Super easy build. Sorry about the crappy pic.
Well it’s coming along and now it’s time to install the motor and jackshaft. I want a motor that will scream at high rpm but not go fast as it is a bit dangerous to ride. I’m thinking low gears? Any advice for this newbie would be great
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I see the kids trike in her & like! Stock kit motor and 54 tooth will keep the revs up and speed down and really climb the hills without pedaling unless you want to. Narrow rear axle and high saddle position is going to make her quite prone to tipping so really slow is really good.
Rick C.
Rick C.
Heck, I say get something with a centrifugal clutch setup, ditch the crankset all together, and throw some little 16s on the back.
Really digging the build idea man!
Really digging the build idea man!
Thinking maybe a shift kit worked in to use the 7 speed sprocket............Curt
Ever think about running a rear axle step plate on the rear axle, like an original Radio Flyer sported? Pedal/push or buddy step and add a clip on rear basket or tray bed for occasional shopping trips. Quick removal setup.
I love these throw back nostalgia/tribute builds for adults, they just appeal to the remnants of the little kid in us.
Rick C.
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Rick,
Yes this is my challenge right now is the rear step. I’m not sure how to fabricate one. I have an original but it’s just too small and looks dumb. If you have any idea on what to use I’d be all ears. Here is a current photo of what she looks like
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Extend the top spring mount down, may have to make a new longer one, or have it cut and extended.........Curt
Like Curt said, extend the tubes 3/4" but I've no idea of your metal working skills and some are required to do it this way. 24" wheel and a wide tire is a simple way that's quick, clean but not free. Don't grind the fork tubes they are really thin wall tubing & safety is always top priority.
If you decide to go the tire wheel change out you might consider using a 24" front electric motor hub, that really simplifies the motor and drive setup 350 to 500 watt 36 volt will roll you faster than I'd want to go on your trike 20 + mph easy...don't get me wrong I love the idea of gas powered it's just a lot more work to get rolling and keep rolling.
The step plates I remember would require a bead roller and some sheet metal skills to duplicate. If you can settle for "in the spirit of" a pedal trike... treadplate or expanded metal on a metal frame both cut to the appropriate shape and size can be considered. I've built some pretty complex shapes using 1"x I/8" strap steel shaped around wooden forms. Then tacking the top (step plate) to the strap frame & then removing the wood form. Easier to do than to describe however, if you have some metal working skills.
Is the "trike section steel"? If so attaching the step platform is also somewhat simplified...I've found not many feel confident nor have the equipment to properly weld aluminum.
Rick C.
If you decide to go the tire wheel change out you might consider using a 24" front electric motor hub, that really simplifies the motor and drive setup 350 to 500 watt 36 volt will roll you faster than I'd want to go on your trike 20 + mph easy...don't get me wrong I love the idea of gas powered it's just a lot more work to get rolling and keep rolling.
The step plates I remember would require a bead roller and some sheet metal skills to duplicate. If you can settle for "in the spirit of" a pedal trike... treadplate or expanded metal on a metal frame both cut to the appropriate shape and size can be considered. I've built some pretty complex shapes using 1"x I/8" strap steel shaped around wooden forms. Then tacking the top (step plate) to the strap frame & then removing the wood form. Easier to do than to describe however, if you have some metal working skills.
Is the "trike section steel"? If so attaching the step platform is also somewhat simplified...I've found not many feel confident nor have the equipment to properly weld aluminum.
Rick C.
Bob I mentioned not ever grinding on the of the fork tubes, but I wasn't intending that to include taking a bit of material off the top stand offs of the front fork leg; where the bottom of the springs bolt up or reducing the spacer height at that point and that may be what you were referring to having ground down a bit. If you did this you could safely gain a quarter inch or more space. If that's not enough then the springs themselves can be cut off at the bottom to gain whatever space you require to gain tire clearance. A simple hardened washer then added to the base of each spring and the original rubber spacer/bumpers re-installed before re-assembly. Remove the minimum amount of spring required as well; it won't take much as we're dealing with "compressed" height here. When the cut is made on each spring, grind a flat on the bottom of each to emulate the original springs "seat" finish to the bottom of each spring. Also the washer needs to fit tight to the spring bolt, so two undersized washers may need to be drilled out to closely fit the spring bolt. Also a short a spacer bushing will probably be required on each bolt to keep the spring vertically aligned under compression. To clarify what I just wrote look how the spring base looks before cutting it off, it narrows to the diameter of the bolt to keep the spring from "wandering" from vertical under compression. The bushing fills the interior space created by cutting the spring. the bushings needn't be more than 1/2" thick and the diameter a snug fit to the interior of the spring base, The bushing goes inside the spring and I kept in place with two nuts locked together on the spring bolt above the bushing.
An alternative to the interior spring bushing is an exterior spring base alignment "cup" keep the spring located vertically. The cup made from thin wall tube with a washer welded to one end 5/16" total cup height should do it. Tube outside diameter snug fit to inside of spring. The washer diameter is greater than the outside diameter of the tube. And all welds are made inside the tube. The washer hole again is a snug fit to the spring bolt.
As you can see Bob lots of ways to skin a cat...some are just easier some more costly, better, worse or just less obvious.
I use to build motorcycles and my favorites used springer forks. I've encountered many problems with springs along the way & know these are simple solutions & relatively inexpensive fabrication suggestions, but not necessarily the best if money and time are not important.
Love the kids tricycle concept no matter how you solve the problems.
Rick C.
Properly fitted as described and the forks will look and function normally...and most importantly safely and with zero added cost. Also you get to keep the big wheel look of that tire and wheel combination.
Rick C.
Zoomed the picture up and his rockers are angled up in front instead of down, you have something wrong up top, head tube to long? Don't know how big or tall the rubber bumpers are, but you have 2 on top. If it is the front spring mount or fork part that is rubbing, the only thing that will cure it is make longer tubes legs easy for welding shop, or machine shop. Best would be to have spacer machined Best would have spacers machined the size of the legs, with extensions to fit inside of the tubs. This would give clearance on main fork as well...........Curt
Curt, good eye, it looks like he's added a stack of spacers underneath the head tube & that's a huge mistake if required they always go on the top of the headset after the steerer is cut, for some reason I can't get the photo to enlarge so I'm not certain but it's the only explanation if the head is completely "drawn up" tight. The frame he's using is a 1 &1/8" headset size so I've seen guys try to use 1" size fork with out using adapter headset & using a threaded style fork rather than the threadless and star nut style.
Yep took another close look and there appears to be a big stack of silver spacers between the fork race and the bottom headset race.
Bob if you would post a close up of the bike head where fork joins to the bikes frame. I'll find a photo of this style fork installed correctly & post it.
Curt I do disagree with the thought that cutting and extending is the best or only way to gain room on this type fork 'cause I've done it several times in the past several different ways, but this appears to be simply an installation error.
Rick C
Yep took another close look and there appears to be a big stack of silver spacers between the fork race and the bottom headset race.
Bob if you would post a close up of the bike head where fork joins to the bikes frame. I'll find a photo of this style fork installed correctly & post it.
Curt I do disagree with the thought that cutting and extending is the best or only way to gain room on this type fork 'cause I've done it several times in the past several different ways, but this appears to be simply an installation error.
Rick C
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