Gas or ebike?

GoldenMotor.com

haste

New Member
Aug 2, 2009
131
0
0
af
Have a nice trek mtb for china girl or electric dd hub motor. I wanna do ebike, but I don't want 8 mile range and 35 topend... An batteries that could burn down my house.. Ideas? Can a 80cc motor get up to 40 with mods?
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
40mph is pushing it. Youy've got a bicycle, not a motorcycle. 25 to 30 is a reasonable speed to expect from a non-modified engine. Don't be fooled by some of the speed claims you'll see posted here. 40 is possible but not without some modifications and some clear understanding of the engine and drive trane.
There is battery technology available to allow a longer range but be prepaired to spend some $ for them. Check out our electric bike section for input on e-bikes.
Good luck, ride safe.
Tom
 

wheelbender6

Well-Known Member
Sep 4, 2008
4,059
221
63
TX
I agree that 40 mph is probably your upper limit with a china girl motor.
You can make an electric bike that will do 40 mph, but it is very expensive to make
an ebike that will do that speed for longer than 15 minutes.
An ebike won the last Spookytooth Death Race. I have not seen any details or specs on that ebike.
 

fasteddy

Well-Known Member
Feb 13, 2009
7,440
4,877
113
British Columbia Canada
Go to the Endless Sphere site. There are the best of the best electric bike builders there. Ask questions and you will get answers.

My bike is built to go 20 mph with a 500W geared hub motor and a 36V lithium polymer battery with a 20 mile range. Cost of the battery and hub motor? Close to $1,800.

It's legal everywhere I go. I weighed this against the $5.000 fines some of the members have been given for having gas motors on bicycles. Check you local and state laws first.

My current build has a 98cc gas motor and a 2 speed transmission which puts it the motorcycle status. Can't ride it on the road where I live since I can't register it. Needs an approved makers assigned vin number. At least I can say I built it.

Steve.
 

Mozenrath

New Member
Jan 13, 2011
340
0
0
California
^^ Rawmotors.com still has kits but they're way expensive. I think gasbike.net also has kits, and you can still get kits on eBay.
 

Tahq

New Member
Sep 2, 2011
45
0
0
Corona, CA
I looked into electric originally myself, I have even built a small solar set up that I could use to charge.

When I reviewed all my options I decided the best bang for the buck for my needs was a four stroke kit. There are a few a few vendors on this sit that sell kits. If you go that route make sure you buy a kit with a decent gearbox...Grubee 4 or even better the Q-matic, just depends on your budget.

If your you want to push toward 40mph you could also look into a shift kit, SBP seems to be the named favorite on site. Do a few mods, change a few sprockets, and you can get to what you are looking for speed wise...just remember you would be doing 40mph on a bike.
 

Venice Motor Bikes

Custom Builder / Dealer/Los Angeles
Mar 20, 2008
7,266
1,797
113
Los Angeles, CA.
You'll never get any real performance from a hub type electric bike! I've ridden them, they're dogs! :(
The E-bikes that performed well at the MB races were full on custom race bikes built by guys who really know their stuff. (& also had some big time coin into them.)
& I don't care what the 4-stroke guys say... Pound per pound & dollar per dollar, you'll get the most bang for your buck from a 2-stroke. ;)
 
Last edited:

Tahq

New Member
Sep 2, 2011
45
0
0
Corona, CA
& I don't care what the 4-stroke guys say... Pound per pound & dollar per dollar, you'll get the most bang for your buck from a 2-stroke. ;)
Ay, leave us older, easy cruising, trailer pulling, don't want to mess with mixing guys enjoy our four strokers!

If you want go fast and save a few bucks the 2 poppers are the way to go, but if you want to leave your blinker on for 23 miles and hear yourself mumble while having a little more dependability consider a four stroke.

Both engines have there pluses and minuses, just do a little research and see what is a better fit for you. There are some great builders and kits on site that can fit your needs. Agree, though, that the electrics I looked at where heavier on the wallet for what I wanted.
 

haste

New Member
Aug 2, 2009
131
0
0
af
Yeah, a hub motor, better controller, and batteries (lipo) will be around 800 bucks. Could build a full 2 stroke, shift kit , sbp pipe, NGk plugs , and all for 400 max including the kit. Sad thing the electric will have a 15 mile range and batteries only last a year lol.

Are the 2 strokes not coming into us anymore?
 

biknut

Well-Known Member
Sep 28, 2010
6,631
409
83
Dallas
Have a nice trek mtb for china girl or electric dd hub motor. I wanna do ebike, but I don't want 8 mile range and 35 topend... An batteries that could burn down my house.. Ideas? Can a 80cc motor get up to 40 with mods?
The answer is yes, a good running China Girl will do about 40 mph top speed with a 36T sprocket, but cruising speed will probably be about 35 mph. If you plan to go that fast, a lot, you better have a good quality bicycle, with good brakes.