I started planning motorizing this bike a few months ago, I finally got around to it. I made the rear mount to move the engine forward so I could use a expansion chamber, I didn’t like my first design so I redesigned it and made it a lot stronger.
Electra Townie
- Thread starter Greg58
- Start date
The silencer is a piece of chain link fence top rail, I have the rear mount welded to the silencer with a set screw to clamp the silencer to the pipe. This is the third silencer I’ve made for the expansion chambers on my bikes, the geometry is wrong on all of the pipe available, the outlet or stinger should not be the same size as the header pipe. The stinger on the silencer is around 60% of the header pipe, I got that information from Gordon Jennings and Graham Bell. All three of my bikes run great and sound good too.
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Don’t worry, I took the front fender off after I took the first picture.
That is my oldest engine, it a GT2B Grubee made in September 2010, I pulled the cylinder before I put it on the bike and that cylinder is worn bad, the thing is it runs so good. This is the engine I had on the 24” tire bike, I’m way too tall for that bike, I felt like a spider on it , all legs.
KOOOL! I like it and you pipe also. 50cc? I have one being worked on now, build this summer if we ever get it, still rain and snow..........Curt
Although small frames are used on bikes with 24" wheels, small frames are common on all tire sizes. For a proper fit you need the correct frame size and geometry for your particular body build.
Here's my favorite frame size calculator. This calculator will give you the ideal frame geometry for your particular body build if you could have a custom frame built. Therefore you can use it to search for manufactured frames that are as close as possible to your ideal frame geometry regardless of what the tire size is.
Bike Size Guide | Competitive Cyclist
New Bike Size Guide Launching 11/17/23
www.competitivecyclist.com
Jerry I knew when I built that bike it was too small, I put it together using spare parts I had, the bike was our son's. He got it for Christmas when he was 11 or 12, he's now 36. I'm putting the bike back better than stock so his son can ride it in a couple of years.Although small frames are used on bikes with 24" wheels, small frames are common on all tire sizes. For a proper fit you need the correct frame size and geometry for your particular body build.
Here's my favorite frame size calculator. This calculator will give you the ideal frame geometry for your particular body build if you could have a custom frame built. Therefore you can use it to search for manufactured frames that are as close as possible to your ideal frame geometry regardless of what the tire size is.
Bike Size Guide | Competitive Cyclist
New Bike Size Guide Launching 11/17/23
I've done a lot of work on that engine, I've ported it and ramped the piston, I've got the jetting just about perfect for a 80 degree day. I used my degree wheel to record the specs so I can try to duplicate them when I have to replace that cylinder.
This engine timing stuff that Gordon Jennings and Graham Bell talk about in their books makes me feel dumb, the more I read the more I get confused. Lucky for me my grind and try method didn't destroy the cylinder. It is very fast for a 48cc, it will run with my neighbors 69cc.
Ramping the piston lowered the compression, I got the measurements and plan to adjust the ports on the next cylinder to keep the crown of the piston stock to keep compression and squish, it should help performance.
That would be me also, just don't know that much about the internals of 2 stroke when it comes to tuning, so having a friend doing it...........Curt
I've got to clean up the cables, the shift cables run inside the frame, along with the clutch, throttle and both brake cables there's a lot going on up front.
My Sidewinder is only ment for someone less than 5'10" tall, I'm 6'2". So I extended the handlebar stem to where I ride in an upright position.
I point this out to others just because the wheels are larger, it doesn't mean the bike is necessarily ment for a taller person.
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Being tall is not what people think it is, I've got scars on my head from bumping into things, I'm only 6'1". When I try to get behind the wheel of my wifes suv I have to move and lower the seat before I can get in. RV beds are another problem, none are long enough.
Curt when you build another bike you can name it the "CF Flyer".
All the hair got rubbed of the top of my head walking under stuff lol
I have the same problem, I sleep on my side so that takes car of it........CF Flyer sounds good. LOL......Curt