Bicycle Engine

GoldenMotor.com

what type of bicycle engine do you have

  • 2 stroke bicycle engine

    Votes: 348 79.6%
  • 4 stroke bicycle engine

    Votes: 79 18.1%
  • electric bicycle motor

    Votes: 4 0.9%
  • hybrid (more than one motor type)

    Votes: 2 0.5%
  • All the above

    Votes: 4 0.9%

  • Total voters
    437

BarelyAWake

New Member
Jul 21, 2009
7,194
21
0
Maine
Hope ya'll don't mind I added a "hybrid" option & reopened the poll after Easy Rider posted, I think it's too interesting to let time out...
 
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Otero

Member
Feb 1, 2010
782
17
18
wa
Bikeguy Joe,
Comparing an HT to a Yugo is an insult to the Yugo. My
nephew still drives one he got in "85. show me an HT that
lasted more than 2k.
I suppose I vote has to go 2 stroke, but I'm still fond of
My Honda GX35. It's a very dependable little engine. For
2 stroke, it has to the Tanaka Pf4000. Not as powerful as
some of the in-frame rice grinders, but the quality is vastly
superior.
Oh yeah, Biknut, If I knew what I was doing, I wouldn't
need the forum.
 
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bigbutterbean

Active Member
Jan 31, 2011
2,417
3
38
Lebanon, PA
I used to run an ht engine. At first, I was ok with the power it made. I pedaled up hills and liked the speed on the flats. But once I realized I could make it better, I tried to. I added a pipe, a hi-comp head, did a few other things. Had an electrical problem, and it was the straw that broke the camel's back (had a lot of other problems along the way, dumped about $1500 into that bike). A buddy offered me a 98cc 4 stroke for $50. The bike cost me $800 altogether to build (new frame and built the entire bike piece by piece), and has been much more solid and reliable from day one than my ht bike ever was. And the kicker for me is that the 98cc engine has more power stock than my ht did with the performance parts. I've gone 4 stroke and I'm NEVER going back to an ht. There are other 2 stroke engines out there with decent power that are solid and reliable, but the ht's just aint it.
 

truckd

Well-Known Member
Oct 19, 2010
2,837
134
63
palmdale calif
I catch a lot of flack from others who think I go over the deep end when I rebuild an engine right outta the box, thinking that I'm adding all the speed stuff for speed but I've come to learn that key word you mentioned "RELIABLE" and the speed stuff does enhance reliability over the kit crap! with the extra capabilities of a couple ponies behind ya.
I just bought my first 4 stroker this week end, a Honda GC160 QHA1 so in just a little while I'll be entering into another world.
YEEE! HAAAA!
 

bigbutterbean

Active Member
Jan 31, 2011
2,417
3
38
Lebanon, PA
The power curve on a 2 stroke can be predicted. Its a little complicated, but basically just boils down to math and geometry. There are probably even computer programs that can help you. With a certain size cylinder, certain size combustion chamber, certain amount of compression, certain header length and certain volume and shape expansion chamber with certain amount of cones and a certain air-fuel mix, jetting, gearing, reeds, etc, you will get x amount of horsepower or torque at x rpms at x gear ratio. Two strokes are just as predictable when you understand how they actually work. And even if you don't know the math or geometry, it only takes a few rides to get used to the powerband, then it becomes predictable. Install a tach and you'll know EXACTLY what your peak rpm's are. Sorry, but there is nothing mystical about a 2 stroke's powerband.
 

bigbutterbean

Active Member
Jan 31, 2011
2,417
3
38
Lebanon, PA
Met a guy today with a very interesting bike. Grubee GT2 (or GT2-A, not sure of the difference), Arrow motor, Sturmey front drum, Manic hub adapter, sbp expansion pipe, etc. Said he's had nothing but problems with it. Most commonly broken piston rings, but other things as well. Said he's done throwing money at it, and he's upgrading to a ktm clone. It doesn't surprise me at all.
 

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
Some years back I started this madness with a series of Tanaka Bikebug motors, friction drive with a whopping 26CC's of raw power. Ha!

Moved up to several China girls with better power and bigger problems. Then a 79cc Harbor Freight which was a step up in power and reliability.

Had an early version of the Golden Motor pancake motor (front wheel) and tried it both by itself and in combination with a China girl. Liked aspects of it, but the lead acid battery weight was a deal breaker and the electric has been sitting on a shelf. It is now off the shelf and will be part of a 63 Schwinn American Deluxe hybrid mated to a pull start china girl converted to tricycle. Battery weight will be less an issue with a trike and the batteries can be lowered to just above the rear axle. If I like it then someday it will get the newer, more efficient batteries. This will be my geezer ride when I am truly an old fart. This is a back burner build.

Three bikes are a return to 2 strokes, but not China girls. One is a vintage British made Villiars midget of 98CC's which reportedly run forever. This build is a 1934 Elgin. The slower revving engine was made for Atkins rotary mowers and I'm running it through an SBP shift kit to a three speed Sturmey Archer rear hub. Had hoped to finish it this summer, but won't. No hurry. Should be a classy, fun ride.
Another quality 2 stroke is a model 1932 Fitchell & Sachs German light motorcycle engine of 98 CC's with a built in 2 speed transmission. What can I say? German engineering and the engine was made in 1934. It's a long ways from China. The engine powers my Indian Hiawatha build which is ongoing for over three years now. The bike converts from a two wheeled light motorcycle to an early Indian inspired tri-car. Work is scheduled to resume on it in August. Don't know when it will be done, but should be on the road a year from now. Its a handsome bike.
The other 2 stroke is an American made 147CC Jacobsen with reed valve Walbro carburetor. It is to replace a 99CC Harbour Freight Predator engine on a 51 Panther build "American Flyer", the one with the modified Grumman canoe sidecar. The Predator is a fine little engine but I need more power for this heavy bike. Circus bear, dog, heavy duty bike with Suzuki fork, sidecar adds up and needs more power for hills and such. The Jacobsen is compact and appears to be very well made. We'll find out in a few weeks. It is small enough to possibly pass for 50 CC's. This is one reason for my shift back to 2 strokes... more power in a small package than a four stroke. I could never pass off a big Preddy engine or a 5 horse Briggs around here pretending it was 50CC's. I'm trying to stay under the radar, so far successfully. I want the motors to look and sound pretty innocent. If stopped with the Jacobsen and asked what displacement I will mumble the hundred and be clear in saying 47CC's. Also have another 2 stroke project which uses a 50CC Tomos moped engine in an AMF Roadmaster frame. Still need to figure out the wiring on it and lace up new wheels. This one has a two speed transmission. Back burner build.

A second 147CC Jacobsen is being readied for an upcoming build over the winter, a Whizzer inspired belt drive 51 cantilever Schwinn with in frame copper gas tank made by Tinsmith, Hercules light motorcycle fork, fatty tires and will be referred to as "kindalikeawhizzer". It should be a smooth and fast ride. I may give it to my youngest son for his 34th birthday next spring. Wanted to do something with a rear sheave and suspect this will be my last build. After that it is finishing up the other ones and doing make-overs of what I have when I get the urge to tinker.
SB.

That's enough motorbikes. This is crazy. But its been fun!
 

maniac57

Old, Fat, and still faster than you
Oct 8, 2011
4,484
22
0
memphis Tn
Bikeguy Joe,
Comparing an HT to a Yugo is an insult to the Yugo. My
nephew still drives one he got in "85. show me an HT that
lasted more than 2k.
I suppose I vote has to go 2 stroke, but I'm still fond of
My Honda GX35. It's a very dependable little engine. For
2 stroke, it has to the Tanaka Pf4000. Not as powerful as
some of the in-frame rice grinders, but the quality is vastly
superior.
Oh yeah, Biknut, If I knew what I was doing, I wouldn't
need the forum.
I recently sold a bike with an HT that had well over 10k miles and the new owner rides it to work every day.
Totally stock engine with a homebuilt tuned pipe, 36 tooth sprocket and welded tensioner.
Look at my first Pig for details.
 

Theon

New Member
Jan 20, 2014
1,440
6
0
FNQ Australia
All depends on how much you enjoy working on it.
If you run any of the Ht's I've got off Ebay without total strip, and a 'timed port job', It will be a Pig.
If you rebuilt your motor from the start instead of hoping someone got it right for a change, then you'll probably know how to fix it.
If you take the time to learn, 2 strokes are far more challenging in getting them to do what you want but also more rewarding, especially for money spent.
I see some really nice aftermarket bits for 4 strokes if you got money to spend.
But I can turn a Au$180 E bay motor, with all the bits you need!, into a 50 Mph motor for the cost of a few tools that wouldn't come near what you'd have to spend to get the 4 stroke in the bike and competing.
That's if you get lucky with a well balanced crank in your Ht however!
I'll stick to two strokes, I have to fix 4 strokes at work!
 
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Otero

Member
Feb 1, 2010
782
17
18
wa
!0 K, hmmm, I suppose it could one in a million, if one
spent enough time on ... fabrication.
 

phatcruiser

New Member
Sep 23, 2013
95
0
0
San Diego
I have a staton friction drive powered by a Mitsubishi clone. 1.6hp, .910 roller to pull all the hills around here. Top speed is 22 mph(verified by a portable mph reader that cities park on the side of the road to get people to slow down) mounted to a Phat Seabreeze with a sturmey archer 90 mm drum brake laced into the front wheel.

I went with the cheapest most reliable kit I could find. So far it has performed flawlessly and pulls me up the steepest hills, the gearing on my bike is so low that pedaling is futile unless starting from a stand still.

If I wanted to go faster I would buy a wr 250 to ride on the street. My bike as it sits now is perfect for 20 mph. Any faster and I would have to move to a MTB or replace the wheels and fork on my current ride. I like that my bike doesn't look like a motorcycle. It is a motorized bicycle and that is all it is.

If/when electric bikes and the batteries come down in weight and price I will consider getting one. **** a decent battery costs more than my whole kit. sLA's are wayyyyy to heavy. Finally their range is way to short. 2strokes are lighter and just as reliable as 4 strokes if you buy the right engine. I don't have the time, tools and garage space to work on a ht motor and I definitely don't have the talent. It was all I could do to mount the friction drive. Lol. So for me, the staton FD is cheap, reliable and I could install it with my limited skills.
 

WECSOG

Member
Nov 10, 2014
138
13
18
North Alabama, USA
I have a chinagirl 2 smoker on my Murray Westport.
I also have a Monkey Ward (Huffy) Open Road that was given to me as a complete pile of trash, 100% coverage rust and non-functional. I got it rideable with zero dollars invested, and I'm thinking about continuing the theme with a Briggs and Scrapmetal vertical shaft mower engine converted to horizontal. .wee.
 

Otero

Member
Feb 1, 2010
782
17
18
wa
Sounds really ugly....I like ugly. My motor is on a $15 bike that's
been painted 3 times,..& not professionally. It's ugly, but it rides
pretty. Before that I rode a $15 Huffy 'til the frame cracked.
I miss it, but it lives on as parts on the solid frame of my current
$15 bike,the make of which i have yet to identify.
 
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WECSOG

Member
Nov 10, 2014
138
13
18
North Alabama, USA
Sounds really ugly....I like ugly. My motor is on a $15 bike that's
been painted 3 times,..& not professionally. It's ugly, but it rides
pretty. Before that I rode a $15 Huffy 'til the frame cracked.
I miss it, but it lives on as parts on the solid frame of my current
$15 bike,the make of which i have yet to identify.
Yep, if mine had been any uglier the guy I got it from would've had to pay to get rid of it! laff
 

Otero

Member
Feb 1, 2010
782
17
18
wa
Well Curt, if your referring to Chinese 4 strokes, I am far more than a little
disenchanted, and my GX35 has been a bit of annoyance of late. The PF4000
Tanaka has yet to give me any grief after 3 years.
 

FFV8

New Member
Oct 29, 2013
551
16
0
Spring Valley NV
I have a chinagirl 2 smoker on my Murray Westport.
I also have a Monkey Ward (Huffy) Open Road that was given to me as a complete pile of trash, 100% coverage rust and non-functional. I got it rideable with zero dollars invested, and I'm thinking about continuing the theme with a Briggs and Scrapmetal vertical shaft mower engine converted to horizontal. .wee.
Rack mount the Briggs with the shaft vertical, borrow some Corvair technology with a belt & away you go.

.