700c Road Bike w/FWD

lowracer

lowracer

New Member
I found this road bike being thrown away behind a local sporting goods store. I threw it in the trunk, took it home & took it all apart. It started as a project to build a long bike with two seats and motorized, but after riding it around pedal only, I decided against it & built this instead. I bought nothing new for this project so total expense was zero & it went together in a few days. I took it on its maiden voyage yesterday and all went well with no issues. Here she is.
-Lowracer-
 

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AV,
The front wheel is actually a rear wheel threaded for a freewheel. The freewheel is a flanged ACS Crossfire I got from SBP (mid priced unit). The 44T chainring (also from SBP) bolts onto the flanged freewheel. It allows using chainrings larger than 22T which is about the largest I've seen available. I could have added another chainring or two and used the rear derailleur tensioner up front to have another gear or two, but its simpler this way (K.I.S.S principal) and lessens the risk of chain derailment. Also on a no-suspension bike, anything over 30 mph gets sketchy.
CB2,
LOL, yeah it is similar to 'The BEAST V.2' but this one is chain drive vs. v-belt drive. I really like the freewheeling aspect (no drag). I enjoy pedaling in the stiffest gear I got while hitting the gas. It accelerates very quickly under hybrid (both human & gas) power.
Its a fun ride and looks like a regular bike like the old Tanaka front friction kits from yesteryear. My plan was to not spend any money and build up with parts & stuff I had gathering dust.
The SBP parts were purchased awhile ago for a shift kit project that never happened.
-Low-
 
Very cool build! Innovative mount! I really like the bar clamp top mount. Ingenious!
 
maniac57,
Here's a close-up pic of this very simple handlebar mount using 1/4" aluminum bar to mount the pocketbike tranny & a small piece of 1/4" angle aluminum mounted to a 1-1/4" McMaster clamp. Also a pic of the blue front rack yoke (a cut-off seatstay from a Cannondale aluminum frame I found). The mount is very lightweight and without flex.
-Low-
 

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I received a new pocket bike gearbox (Motovox 5:1) in the mail yesterday since the one I had was too noisy compared to the 5 others I have owned. I installed it this morning & it is nice & quiet (ahhhhh). I also re-installed the black plastic engine shroud I had originally removed from the Tanaka 40cc so now I'm good to go. I also swapped the drive cog back to 12T from the 10T I was running.
-Low-
 
Donor bikes always get the bravest modifications. :) Very clever design, Low. Does the extra weight up front make it difficult to steer?
 
Lightning Boy,
Thanks.
The extra weight up front doesn't negetively affect the steering. I had a front engine bike in the past with a much heavier Lifan 97cc engine and it handled just fine. Back in the old days us paperboys attached plastic milk crates to the front of our bmx bike handlebars and filled them full of newspapers. As long as the weight wasn't too forward of the front axle, the bike handled fine but was difficult to park unless leaned against a wall.
By seperating the engine driven front drivetrain front the pedal driven rear drivetrain, the bike is as easy to pedal as it is to motor, since the drivetrains don't drag eachother (both freewheel).
-Low-
 
Here are todays pics of the changes to the bike.
-Cheers-
 

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OK LR guess Im on the right thread now? Love this build. You always manage to arrange bike parts in the most interesting way!
 
CB2,
Thank you sir.
This is one simple build.
I really like riding this one and pedaling along in the tallest gear I got.
Might just change out the saddle & the big ring and its done.
I found a throw away pink Razor Sweet Pea kids electric scooter yesterday. The note said 'Free, just needs new batteries'.
I stripped the dead batteries, controller and motor and pumped up the tires. Woohoo, they hold air.
My daughter will definitely want me to slap a gas engine on this one.
Not sure yet if it will get a friction drive or chain drive.
Will start a new thread once the build begins.
Cheers,
-Low-
 

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Aleman,
Nice install!
I am looking forward to motorizing this little scooter.
Sure like to find me another Tanaka PF3300, but not for the big bucks.
-Low-
 
I installed a spare set of clipless pedals I had laying around (Shimano 747's) & took the FWD road bike for a quick ride around the neighborhood. This bike is a blast to ride fast and I really love taking off from a dead stop. I leave the pedal powered gearing in the hardest gear I got (48/11) and pedal hard going WOT. I get going faster than most cars and once up to about 30 mph, I get aero and quit pedaling. I have switched the engine sprocket back to a 12T (from the 10T) and am still running the 44T on the front freewheel hub. Not sure what the top end is, but it feels a lot like 35-40. Most of the time I just enjoying soft pedaling at around 25-30 mph cruising the neighborhoods but getting up to speed quicklike.
-Low-
 
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