'The Beast' Reborn

[sublunacy]

 

[lowracer]

I worked on the pipe some more and ended up cutting it down a little bit for better performance. Now the distance from the engine to widest section of the expansion chamber is 21". I also added a rear muffler brace for a second mounting point also using rubber grommets for vibration dampening. I just need to cover the rest of the pipe with header wrap and its good to go.
The pipe definitely has added power and sounds mean.
-Low-

 

[rawly old]

Hi Low,
Here's my resurrected beast. At one point I was so bummed
that I started to buy a G.E.B.E.,but after going over the install
requirements & other limitations I found my stays were too narrow
for the kit and a PF4000 likely a bit too much engine.
Sooo...I thought about what had been wrong with my earlier belt
drives. The 1st with 20" rim sheave & gx35 worked fine on the flat
& was fast, but didn't climb. 2nd with the 24" rim had great low end
with the gx, but wanted to slip. So 3rd was with the Pf4000 which
stripped the threads right off the shaft. A single factor was causing
the problems. Because the angle of the belt from pulley to sheave
was obtuse, too much tension on the belt was needed to make it work.
Simple fix, now with the belt encompassing 50% of the pulley it functions
with 1/2 the tension. With my Belleville washer pulley, which compresses
around the belt, I went back to a 20" rim( 15 1/2 dia.) & a 3/4" pulley
for a ratio of 20.6 to 1. With the Tanaka that low enough climb, high
enough to cruise at 30.

 

[rawly old]

Yeah, I know it looks a lot like the GEBE, but I've got a wedge belt
instead of cogged sheave & pulleys & this setup's built way tougher.
It's also more precise than the old builds; my wheel & sheave are to
+1- mm in both directions & the wheel's balanced. This is my stealth
tourer. That curved piece of tubing holds the pannier away from the
pulley & slides like a trombone when I need to move the struts. It
also stiffens to frame against vibration.

 

[lowracer]

Lookin good Rawly!
I never did have much success putting too much tension on the vbelt to increase friction. I actually bent a rack once trying the high pressure idea.
I am missing my old Tanaka 40 since selling the Banshee Scream bike powered by that engine.
Still running the Tanaka 47r & TC47 on two different MB's currently.
-Lowracer-

 

[rawly old]

Yeah, the old blue Huffer died; this is my new $15 dollar bike,
a boneyard rescue with a much more robust frame. $5 for
the Samsonite carry-on converted to an in-frame. The
green bag has a surplus marine bivy with a $15 walmart
fleece bag inside. The rear pannier is good camo and a
sound dampener. Pedals surprisingly well with the belt
disconnected, not as heavy as it looks. No more struggling
with a wet friction drive.

 

[cpuaid]

that is one tough looking bike. i am a huge fan of recycling bikes and have never paid more than $30 for any of my motorized bike frames.

 

[lowracer]

I've changed the pipe on 'The Shifty Beast' once again to give more clearance for pedaling.
I also wrapped it using 15' of 2" black header wrap.
Next is to improve the chain management running from the engine to the big ring.
I cut a groove into two skateboard wheels and will build a spring loaded scissor like mount using either angle iron or flat bar.
This should allow both pedaling and motorized to happen without issue. Currently, while engine driven it runs perfect, but pedaling slackens the chain due to the rear derailleur. Pedal power pulls the chain down & motorized pulls the chain up. I'm going to shorten the chain to the shortest I can make it before its tight (slight slack). Then each skateboard wheel mounted close to the big chainring squeezing in on the chain and mounted to a single pivot point. When the engine is powering the system, the left side of the chain will be taut & the right side tensioned. When the pedals are powering the system, the right side of the chain will be taut and the left side slack.
Hopefully this will work.
Will post pics & info once mounted.
-Low-

 

[rawly old]

Hi Low,bin a while, my $15 bike above is back to friction again
with an all, (hopefully), weather roller. I just needed more low end,
too many long steep hills here cooking my clutch. Mostly I'm
pedaling this 'Vega mixte these days. Just finished a ride on the
Olympic Discovery Trail from Port Townsend,WA to Neah Bay.
It's a mite slower than the MB. Everything clips on or clips together
so I can put it on a bus which I rode back. It cost me $3.50 to
go 140 miles. Public transit here is dirt cheap. I didn't pay more
than $5 for any of those bags, (mostly from Goodwill).

Greetings from the Ever'green' State