Electra Townie

[Greg58]

I’ve got it pretty much finished, I used a chain guard on this one because there’s a lot of chain exposed with the forward mounted engine. I have to make a rear mount for the chain guard, two black zip ties are holding it for the test ride.

 

[Greg58]

I think it is just about done, I’ve got the mirror on and the wires loomed and secured.

 

[Paul Land]

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.

I have a 2018 Townie, what year is that one it's totally diff looking

 

[Greg58]

I have no idea, a neighbor up the road gave it to me. From the looks of the tires I would say it's 10-12 years old.

 

[Greg58]

Here’s the engine running, runs well to be 12 years old and only on the second set of rings.

48cc Grubee with eBay pipe and home made silencer

Motorized bicycle expansion chamber

youtube.com

 

[Chad_Broski]

Here’s the engine running, runs well to be 12 years old and only on the second set of rings.

cool, what expansion chamber are you using?

 

[Greg58]

It’s the cheapest one I could find on eBay, $30 shipped. I’ve got 3 and all three look about the same. I have one from CDHPOWER that is made and sized the same.

 

[Chad_Broski]

It’s the cheapest one I could find on eBay, $30 shipped. I’ve got 3 and all three look about the same. I have one from CDHPOWER that is made and sized the same.

Okay, I was thinking about doing the same but I seen a lot of people bashing these clones of what seem to be a MZ65.

https://motorbicycling.com/threads/cdh66-pipe-worth-the-mun-ez.67511/post-700187

 

[Chad_Broski]

An excerpt of what I wrote:

"
Negative reviews:

Avoid the banana style and the zeda88/cdh66 pipes, they either add minimal to no power (banana) or add very little power for the money (zeda88/cdh66)
Zeda88/cdh66 (looks like an mz65 but its far skinnier and the header is all wrong)

- extremeodd

the MZ65 will serve you well without the exorbitant cost of a converted dirtbike pipe($170-$200+!)...just make sure its a REAL one and not the zeda/cdh66 knockoff which is much smaller and much worse performance.

- FNTPuck

Don't get cheated and buy the cheaper [CDH66] that almost looks the same [as the MZ65]

- CrazyDan

 

[Greg58]

I don't get caught up in the thought that these won't work, all three of mine were a improvement. If I wanted to do 50mph I would buy a motorcycle.

 

[Greg58]

According to the tuners handbook these pipes are wrong, adding the silencer with the smaller stinger corrected mine.

 

[Greg58]

The weak point on all three is the rear mount, I have added a second on the first two and will to this one also.

 

[Chad_Broski]

all three of mine were a improvement. If I wanted to do 50mph I would buy a motorcycle.

I feel the same way. I am really looking for more low-mid range power rather than top speed. Also good to hear it was an improvement. I suppose I should just get the pipe tonight then, right after I finish reading the "EXPANSION CHAMBERS" section of the Handbook you recommended. Great advice, as per usual.

 

[Greg58]

According to Gordon's calculation the stinger should be 58-62% of the size of the head pipe, mine is right in that range. The longer head pipe increases low end torque, I found that out several years ago when I made a couple of pipes. A 16" head pipe gave the best low end hill climbing torque.