Motorized bicycle build

V

ValleyCenter ACE

New Member
#1
#1
So I'm starting a motorized bicycle build. Yes.. Yes.. yes I know it's not a mini bike, and you could get all technical and pull out your mini bike identification books and demand this to be removed. But I want to post it here anyways.
So I'm going to sum it up here.

- Going to use an existing bicycle frame that is going to be strengthened and used as a guide to make this frame straight.

- Will not be using a cheap little Chinese motor. Those are crap. I will be using a Briggs and Stratton 2.5hp. I like the reliability and simplicity of those flat heads.

- Must be completely finished before a Memorial Day parade!

Pictures will be coming soon!!

And this is what I want it to look similar too. Will see if I can get close!!
Yesterday`s The place where you buy all your antique and classic bikes
 
Stangrcr1

Stangrcr1

New Member
#3
#3
Many of us have done motorized bike builds, including me.



I say go for it. I like seeing how people overcome the issues of putting a motor in a bicycle.
 
V

ValleyCenter ACE

New Member
#4
#4
So I found a better example for what I want my motorized bicycle to look similar to!


I also have to find dirt bike rims and tires because I don't want some flimsy bicycle tires. I'll have to start looking in motorcycle scrap yards to see if I can find anything good. Buying a new set is a little out of my budget!
 
jeep2003

jeep2003

#5
#5
you can look for moped wheels. some of them have sprockets on both sides for pedal starting. Plus being from the 70s they usually have some cool old school tires
 
V

ValleyCenter ACE

New Member
#6
#6
Here is the picture of the frame to be modified! So practically the entire thing is going to be changed. Please excuse the mess, that garage needs some attention!




- The frame needs to be stretched about 4 inch's.

- The entire front section is going to be cut out and then new pipe put into place. 1 1/4"

- The pedal hub will be replaced with a different one.

So alot needs to be done and I haven't even scratched the surface. Need to get brazing rod and a different tip for my oxy-acetylene torch. Sorry I don't have a welder. But I know from talking with alot of much wiser men that brazing will work just fine, as long as the weld goes deep enough. So I will practice alot with brazing and do some weight testing the old fashion way.

Don't really know when all this is going to happen, because of stuff with work. But Lord willing I can find the time.

Jeep 2003- Yeah I was looking into the moped rims. But I need one that is 20 to 21 inches in diameter and those seem to be hard to find. But I won't know until I start searching shops. And the whole drive system will be done with belts so only one gear will be necessary, on the rim, at least. But I have to see.
 
jprice

jprice

OldMiniBikes.com
#7
#7
I did one a little while back, it was fun ,
it has a mini bike clutch system, and I love it ! with that set up you can pedal
like there is no engine on the bike ,and this little motor is great! runs smooth as anything! power is decent you cant gun it and pull wheelies haha, but it cruises pretty good , 35mph is the fasted I had it ,but my avg mph is 15 to 20
which is good for the sections and its nice and quiet .
I want to get some pedal extenders ,with the motor sticking out there is little room for your foot .
need to change the seat ,little hard on the azz ! Lol
would like to find a disk brake set up for it , I think they sell adaptors for the forks for the caliper I would just need a hub and or a disk front wheel .
I was looking into the 2stroke motors but didn't want to have to deal with the gas and oil and the smoke blowing in my face..

I wish I worked closer I would save a ton of money in gas alone ..

good luck with your build , keep us posted for sure !:thumbsup:
 
Paticus

Paticus

Member
#9
#9
I love those 1911 style indians, so cool. Watching this :thumbsup: For what its worth- I built an electric bike and found one of the biggest mistakes I made was not being conscious on the high center of gravity. Something to think about when using a bike frame which already sits tall for ease of pedaling.
 
jprice

jprice

OldMiniBikes.com
#10
#10
Paticus said:
I love those 1911 style indians, so cool. Watching this :thumbsup: For what its worth- I built an electric bike and found one of the biggest mistakes I made was not being conscious on the high center of gravity. Something to think about when using a bike frame which already sits tall for ease of pedaling.
Click to expand...
I seen them electric bikes and some of them wow!! they get up to speed quick!
yeah gotta watch that for sure , im 6'4 so it fits me pretty good , ive seen people put worked 212 cc motors on these things ,now that would be a scary ride lol I would want that bike as low as it could go because it might hurt less when you hit the ground Haha!
hopefully ace keeps us posted for sure !
 
V

ValleyCenter ACE

New Member
#11
#11
Of course guys I will keep you posted! Was just out working on it now, gathering parts and what not. I need to get the brazing parts soon!!

And yes the motor will be mounted below the level of the pedal hub. So the center of gravity will be lower. Preventing easy tip overs.
 
V

ValleyCenter ACE

New Member
#13
#13
Well I'm sorry to inform you guys but this bike won't be a replica! It will be to difficult to make a replica of the Harley I showed. But I want to make a bike that is heavily based upon Harley's design. So we will see! I just need to start cutting metal, because I'm tired of just thinking and writing about this. So Lord willing I will start soon.

So here is a picture of a quick sketch that I have done that shows an idea that I have for the springer front forks. It shows a cut away on the left, and a 4in spring. It's a leading link fork design, that is fully enclosed to try and keep the grease and dirt down.
 
V

ValleyCenter ACE

New Member
#15
#15
Got welding rod and tip the other day! Started cutting and welding that evening!








So I stood and just stared at the frame for who knows how long figuring out what was exactly wrong with it. I put a mock up tire on the frame and I just couldn't put my thumb on it. And I figured it out it was the fact that the first piece I welded on was at the wrong angle. The pipe didn't flow with the angle of the rear forks. So I cut the welds and started again at square one.
Fun fun fun gott'a do things right evening if it means reversing the steps you just took!!



Bikebudy -Well I already have this frame, and it was free, so I don't want to go through the hassle of getting another frame just to do all the same cutting and welding to it anyways, it would only have the build marginally easier. But it's a good suggestion!
 
V

ValleyCenter ACE

New Member
#16
#16
So I did some more work on the frame I'm ready to make the down tube to mount the engine on and weld the neck into place! I'll get better pictures tomorrow Lord willing. Also porting the engine and starting to make it's custom manifold! still a lot ahead but making steady progress!
 
Txpowdercoater

Txpowdercoater

New Member
#17
#17
best advice yet, I dont see anyway your going to make an old looking retro bike with that frame without a million hours bending pipe and welding etc etc etc, I would rather start from scratch built than start with that frame.
get a modern Raleigh Retro-Glide (cheaper than a vintage bike probably), the frame is a lot closer to what you want.


bikebudy said:
To get the look you want, I would start with another frame closer to whats in your photo.

1947 Columbia



sorry, not mine

Motorized Beach Cruiser

http://losangeles.craigslist.org/lgb/bik/4409186191.html

http://orangecounty.craigslist.org/bik/4350824912.html
Click to expand...
 
V

ValleyCenter ACE

New Member
#18
#18
So Sorry guys I have been busy but I have been making progress.... slowly!
So I have decided to stretch the frame about 6 inch's, I decided that the motor and jack shaft will fit alot better in that space. So I have to wait until my father and I can finish a welding table that will be behind my garage instead of being there in that messy garage bay where there's plenty of flammable's, before I can continue on the frame.
So in the meantime I started to port the engine I'm going to use on the bike, it's true the factory castings are pretty bad, and just a little work with a dremel and some sand paper makes them alot better.




Txpowder coat- I'm not going to get a different frame. It's to much of a hassle and I would be doing all the same amount of work. So there's no point in me doing that especial since there is no bicycle frame that is remotely similar to what I'm trying to make my frame look like.

Look at the top of the frame, and see how the curve looks. Exactly !! There is no curve, the frame I'm trying to copy is primarily all straight. So why would I get a curvy frame just to cut it up and replace the pipes with straight ones? So I completely understand the concern! Don't get me wrong! But I'm already pretty far down the road to modifying this frame. So there's no turning back! Since due date is in a month. Sorry did state there was a due date?
 
V

ValleyCenter ACE

New Member
#19
#19
Jprice- What type of engine did you have in your bike?? Because if it's a Briggs then what's the head it has?
It looks like it's be modified! Was it?

Sorry to ask a question! But hey! I'll do some updates! So porting the heads is nearly complete! Working on the manifold which is a tight fit. And finished prepping the inside of the motor for it stand up right! Picture will come soon! And no the new welding table has not been started, so no work has been done on the frame. Which stinks because I want to get working on this again!!!!!!!!!

Found some more springs for the forks so I'll be getting those started soon.

Suggestion for my fellow mini biker's- Look to make springer front fork?? But can't find any suitable springs? Then look into getting your hands on some bicycle or quad or motorcycle front shocks! Any of the motorcycle, three wheeler, front shocks should have a spring that is about an inch in diameter or a little more and is about 2 feet long. So if you can cut it down to usable length's it's great, but if you can't the bicycle shock springs are pretty short. And are perfect for springer front forks.
 
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V

ValleyCenter ACE

New Member
#20
#20
aranhawaii- Those bikes are pretty slick! Sorry I just noticed I never responded to you. Liken those forks!! And do they come with a derringer pistol holster mounted to the frame ??!!!!
 
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