Dual Engine Chopper!

GoldenMotor.com

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
Getting two engines to sync shouldn't be a big issue unless you get one runner and one dog. My dad and I raced go karts back in the 60s and we had several twin engined cars. We ran a separated rear axle. One engine pulled the left wheel the other pulled the right. When they were in sync they made the sweetest sound you can imagine. There was this neat harmonics that would shift from one side to the other, sort of like stereo. Good luck and keep us posted on this build.
Tom
 

Maxvision

New Member
Jun 13, 2009
551
1
0
San Diego, CA
You should keep a fire extinguisher handy with that home made welder!!! (seriously!!)
You should ALWAYS have a extinguisher nearby when doing any welding... period! ;)
Heh...that's a good rule for any tool that creates sparks. I was using an angle grinder to cut some metal on one of my builds, started feeling something unusually warm around my belt buckle. Looked down and my shirt was on fire...lol.
 

jrellpictures

New Member
Dec 3, 2009
23
0
0
Frederick, MD
Dude, I am in awe at your ability and creativeness! Really impressive. I am also very interested in your 2 engine build. I have a few questions. What type of engines are you using? If you don't use a clutch, how do intend on sitting idle? How are you going to tie the two motors output together and get them tuned to accelerate together?
Thank you,

well im using 2 motorbike engines and 1 electric motor. All will be attached to one drive shaft and then off of that, a chain will be attached to the sprocket on the back wheel..haha that sounds confusing. The motorbike engines have a clutch but it isn't a centrifugal one. so you have to have a little speed or the engines will die. so to solve that, i added an electric motor. i will use that to get me up to speed and it will double as an electric start since it is attached to the same shaft as the engines. also, to tune them, i will just have to mess with the adjustments on the carb until i get em synced up.
 

jrellpictures

New Member
Dec 3, 2009
23
0
0
Frederick, MD
J-rell
Congrats on all the heart going into your project.
The metal wholesales/retail sellers also call amounts of metal other than full stock pieces "drops". If you were closer I'd give you all the pipe stock and metal you need.
What's your ideas on sync for the 2 motors? Not like multiple carbs on a single motor that you can sync up. Interesting since I've thought of multiple motor setup myself, but haven't researched the sync issue nor drive setup.
...things that make you go hmmmm.
Have a fun time. We'll be watchin
Alajoyn
Portage MI
Thanks for the tip, it'll be easier for me to ask for some metal. but actually i dont think i need anymore. i have plenty of old bike frames. but thanks anyway. i answered the sync issue in my last post. you can look up there, haha i don't feel like typing it again.
 

jrellpictures

New Member
Dec 3, 2009
23
0
0
Frederick, MD
Getting two engines to sync shouldn't be a big issue unless you get one runner and one dog. My dad and I raced go karts back in the 60s and we had several twin engined cars. We ran a separated rear axle. One engine pulled the left wheel the other pulled the right. When they were in sync they made the sweetest sound you can imagine. There was this neat harmonics that would shift from one side to the other, sort of like stereo. Good luck and keep us posted on this build.
Tom
hmmmmm i didn't think of that. i would imagine that sounds sweet. i wonder if i could get a a different baffle or something to make it sound more beefy. i think i heard taking out the baffle messes up the cylinder and it kinda disturbs the neighbors. but the engines are the same so it shouldn't be too tough
 

jrellpictures

New Member
Dec 3, 2009
23
0
0
Frederick, MD
Heh...that's a good rule for any tool that creates sparks. I was using an angle grinder to cut some metal on one of my builds, started feeling something unusually warm around my belt buckle. Looked down and my shirt was on fire...lol.
You should see the sparks coming from my saw when i cut metal. Sparks fly across my whole garage, i think its beautiful. until a hot piece of metal hits you in the face, thats happened before, not to pleasant. and did you like jump in wter or something? how'd that turn out? one time while i was welding, a chunk of metal burned clean through my jeans and burned my leg. that wasn't to great either haha.
 

jrellpictures

New Member
Dec 3, 2009
23
0
0
Frederick, MD
I Got to work on the chopper all morning and i finally got the engines mounted. i know some people want to see how i did it, so i'll post some pictures tomorrow.

Also, Does anyone have any ideas for a custom tank? i have tons of extra pvc, but i think gas eats pvc pretty quickly, so thats not a good idea. What materials stand up to gas pretty well?
 

The Newbie!

New Member
May 19, 2009
36
0
0
Gilbert, AZ
It's kinda like another guy says on this forum, "if you can see beyond the invisible, anything is possible!" I'll be watchin too! I wanna build a chopper trike with dual engines, that go cart scenario just might work out. You go boy! So when is tomarrow? I Wanna c pics!
 

jrellpictures

New Member
Dec 3, 2009
23
0
0
Frederick, MD
Hey everyone, sorry i havnt posted anything in a while. but i have a huge question. I have seen some pictures online but i have no idea how to make a secondary drive..like a secondary shaft where my two engines are going to be attached....this is most popular on shifter kits..can some one please help?

p.s. for all those that wanna see pics, i promise i'll post some tomorrow....its about 20 degrees in my garage and i cant stand it...sorry for the wait but im on it!
 

Alajoyn

New Member
Sep 28, 2009
71
1
0
Portage, MI
Waitin on a few pix.
Regarding your question, I'll answer it with my own ideas for what I have, a tandem.
If I were to utilize 2 separate motors and keep the $'s to bare minimum, I'd run a drive chain from each motor (located in the captains V and the 2nd in the stokers V) to a jack-shaft containing a gear connecting to each motor. A 3rd gear (on the same shaft) going to my rear wheel. Welding up a tube with berrings and zirk grease fittings ect. I know guys on this forum have great setups with jackshafts. I think using a tandem makes it quite easy since 2motors fit easily with outputs on the same side ect.

Customizing any further (transmission like qualities) by designing the shaft to be able to mesh with a hub assembly for alternate gearing. I'd do this down the road after dialing in and securing safety testing for a while. Suppose you could make the bike do whatever speed you wished this way eh?
By that time just purchase a motorcycle anyway HA!

Right now I'm dealing with stopping power on my tandem. Don't think a front disk conversion will effectivly haul me down fast enough in a panic stop. Looks like I'm going to convert to a rear coaster and pull type pads on the back and on front 1 maybe 2 sets of pull types and going back to my old steel rims with thicker spokes.

Lets see some pix. 10degrees is no excuse! HA. :)

Best,
Alajoyn
Portage Michigan
 

jrellpictures

New Member
Dec 3, 2009
23
0
0
Frederick, MD
Welding up a tube with berrings and zirk grease fittings ect. I know guys on this forum have great setups with jackshafts. I think using a tandem makes it quite easy since 2motors fit easily with outputs on the same side ect.
heyyy, well thats my basic idea i just dont exactly know how to make a jackshaft. if you know of any links with pictures please let me know. also! i got pictures! they're kind of blurry but you can get the idea. The chopper looks a little weird because i have a super small wheel on the front and a normal huge one on the back(these aren't the actual ones i'm using). also the fork is placed a little to far up. i got the main parts cut, i just need to weld em all togethor....check em out!
 

InKedKloWn

New Member
Oct 29, 2009
15
0
0
42
Muskegon, Michigan
That looks like its going to be SwEEt! are you going to keep the scooter front tire on it when finished? that tire is so tiny. might be dangerous in them turns.. just a thought
 

jrellpictures

New Member
Dec 3, 2009
23
0
0
Frederick, MD
Hey everyoneeeeee, well i haven't posted any update in a while and i've gotten a ton of work done on the chopper! im so excited to break it out of the garage when its warm. theres some pictures below. Enjoy!!