New to gassers - Schwinn Cantilever Conversion from Electric

Right, so I was all hot and heavy into building electric bikes. Getting pretty good with them too. But then I screwed up, made a bad decision and burned down my shop,a few bikes, and a couple cars.

BUT WAIT!

This isn't a tale of misery and woe! Nobody was hurt or made homeless. Yeah, things are tight, but I'm in a better place, with a new outlook.

So, onto the bike.


Originally, I built it as an electric you can see it here. Worked pretty good too.

But, I found myself exploring a local state park more so I built this:


It was quick and fun, and a capable off-roader... 'til I hit a tree and damaged the battery pack, and didn't inspect it well enough before attempting to recharge it.

Fortunately, my Schwinn had been cannibalized and left in the back yard for future consideration and thus avoided immolation. After dealing with cleanup, moving and other aspects of aftermath I certainly don't have the budget for an electric build, for now. But I had enough to pick a 66/80cc motor off ebay (BoyGoFast, cheap, free shipping, not the nicest motor and kit, came quick though) and an SBP shifter kit (I've been using their hardware for my electrics and they're essentially local to me). I've never built a gas-powered bike, however, I will certainly admit that the idea had appealed to me. With a few runs to my favorite bike co-op, and the generosity of my partner (she had a few parts I could use), I had most of the pieces to get rolling again.

And here it is, not done by any means, but a good start:

(the tank is that far back to provide space for a battery box)

I got the kit last Thursday and installed and running Friday and have been working out the kinks since. Got my first good ride in today. Man, what a blast! Hard to keep myself in check during the break-in. I've since re-torqued the head, fiddled with the carb and have replaced the petcock, for the time being, with lawn-mower parts.

Most immediately, I'm searching for a proper saddle, better fork lowers (I had cut these for another project) and plan to get a decent 12v lighting system up. More long-term goals include installing a BB-drive electric motor (parallel-hybrid styles) and some light hopping up and re-working of the motor.

I also want to say thanks to this community, without the wealth of knowledge amassed here, my build wouldn't have gone as smoothly as it has.

 

[wheelbender6]

Cool. Unlike an e-bike, you have to break in the gas bike. What kind of kit was your electric kit? It looks like it drives your crank set.

 

[TheCrystalSkull]

Sure do. But I've broke in a few engines, mostly cars.

I assembled my electric gear to use a SickBikeParts shift kit. On the Schwinn I was using a large RC airplane motor and transmission for a battle-bot, when I built the Specialized I used a "400w" Kollmorgan motor, since it contained a controller and was built heavier. I like the RC on paved surfaces better though (the Schwinn could top-out in the upper-thirties), and the ones I use have a comparable speed range and output to the stock HT motors. They just will not tolerate being bogged, or they grenade.

When I add a electric motor back onto this bike, I'll probably use a GNGbikes kit, as it is also a bottom-bracket drive kit and works well if it isn't abused. 'Course that'll create some exhaust routing shenanigans. I also may try and get the gas motor to run as a generator (appeasement of the legislation, and all that), but that's probably needless complication. I'm just trying to take it one step at a time.

 

[TheCrystalSkull]

The electric 'kit'



As you can see it was pretty straight-forward. Motor on top, 13/65 #25 chain to the jackshaft, 10/48 from the jackshaft to the freewheel crank. Motor turned roughly 3,500 RPM. Gave a top speed of 20-ish and decent climbing ability. In retrospect, the four-stroke kit from SBP probably would've been better due to it's design.

 

[TheCrystalSkull]

Got some more work done. Been putting on miles. Hopefully, I will be getting the electric drive components ordered this week.

Motor has broken in nicely, good amount of power and speed (for now).
The new tires are working nicely.

 

[TheCrystalSkull]

Ran my first inter-county run. A mere 13 miles in rush hour traffic, but the bike performed very well. Behaved myself, and averaged 22mph. Thinking about head cooling now, towards the end of the run, I was definitely getting some pre-ignition/loss of power. Ran into a lurker at my destination, we chatted a bit. Very cool.

Set for the return trip

 

[TheCrystalSkull]

Ditching the idea of electrics for now. Got the SBP expansion pipe, ordered a Puch head and stud kit and such. On longer rides there's a definite loss of power; let it sit for fifteen minutes to half an hour and it's all good again. I'm hoping to get more consistent runs out of it.

Chopped up some brake line for fin dampeners, definitely quieter. Thinking about building an airbox since I can really hear the intake over the exhaust.

I feel like I'm learning how to handle the bike better almost every time I ride it now. A little faster through a turn, a realization about the shift points or just finding that quiet cruising speed.

Tool of choice for the less then 20 mile round-trip errands. I've only driven my car once in the last two weeks and that was to haul off garbage and pick up parts for another project.

 

[TheCrystalSkull]

Got the Puch head installed, did some clean up porting on the jug (exhaust port was only a 3/4" circular hole), match ported the manifolds, reamed the intake so it was more consistent. Also, made up a better spark plug wire and some fender stays, since it's raining now. Mid-range power is so much better over a larger part of the powerband after all the relevant work.

 

[TheCrystalSkull]

Spring! Update.

Been a while since I posted about this bike. Over the winter I blew the motor and replaced it. Somewhere along the line I bent the hell out of my jackshaft bracket. Also picked up an expansion pipe. Built up another bike, but the frame didn't fit me how I'd like.

A couple weeks ago a got a wild hair to build a chopper-style springer, and things have just kind of got of hand since.

At the time, my disc brakes wheels were on my other frame as this bike was down. And I wasn't about roll on just rim brakes, I don't even own a coaster anymore, but I had enough parts to build some wheels. So I tried some different sets.

20x3.0 front and 20x4.25 Rear, but these really are for a specific build I have in mind. That and the bottom bracket was too low; at the time I was against chopping the rear.

24x? Front, 24x3.0 Rear. Closer, but as you can see that front wheel is junk. I keep around for test fits, like this.

The were various combinations, tried and I eventually decided to just go with 24x3.0 in the rear and 26x2.125 up front. After all the wheel fitments, BB height correction was needed so started cutting and welding.

Here's were I'm at now:

Additionally, I'm going to add an RC motor to the mix. Bottom bracket drive, LiPo and such. I have a whitewall Thick Brick on the way to replace the old flame-patterned Duro Beach Comber.

 

[TheCrystalSkull]

Been reworking cantilever tubes, as well as the front end geometry.

After push riding it around on my street I decided to decrease the rake a bit for a number of reasons. I have a number of different handlebars, but none seemed to achieve an appropriate balance of aesthetic and ergonomics. I'm not currently interested in fabbing up bars for this ride, given my self-imposed timeline. In addition, I had concerns about handling due to the wheelbase, flex in the fork, and uncomfortable or fatigue-inducing controls.