There are no bike engines that I've seen on a MB that are high performance multi-speeds, the morrinis are fast but only 1 speed. I plan to fix that for my next build. I want to use an engine from a 65cc class dirt bike because they are 5 speed and manual clutch. They make about the same power as a morrini, if not more. I've seen used bikes on Craigslist for around 700, I bet I can get one for less than 600 if I keep an eye on the ads for a while and sell all the unused parts on eBay, maybe get most of my money back! Forks, brakes, swingarm, frame, seat, tank, plastics, could probably get 300 for all that. That means a kick-butt engine for less than 300 plus labor! These things are water cooled and fairly compact engines. The more I think about it, the more it sounds like an awesome idea! An 85 would make more power, a lot more actually because they are designed better, but those bikes go for 2x as much because there's more demand for them. Idk what kind of bike to put it in yet, what do ya'll think? I would do a shifter on the handle bars and coaster brake, and definitely a worksman with the sportsman sprocket adapter.
small dirt bike engine? Kawasaki, KTM, Suzuki...
- Thread starter young grease monkey
- Start date
What I don't get is if you spend $600 to $700 to begin with for a motorcycle why not keep it as a motorcycle rather than spending more time and money to dissemble it to make a bicycle?
Because they are made for people who are 5 feet tall, less than 100 lbs and a dirt bike doesn't look street legal at all. Selling all the extra parts will easily pay for the bicycle and wheels and stuff.
http://www.youtube.com/watch?v=gtnNOomASqM&feature=youtube_gdata_player
BTW, I'm 6''8' 320 lb and the 66cc gt5 doesn't have a problem ttakin me into the 30's.
BTW, I'm 6''8' 320 lb and the 66cc gt5 doesn't have a problem ttakin me into the 30's.
ok, i'm not content with 30mph and poor acceleration. glad it works for you, you get the cheaper way to happiness than me lol.
cool video! the 65cc is way lighter and compact and 5 speed. thats a cool build but i'm going for the best of the best
cool video! the 65cc is way lighter and compact and 5 speed. thats a cool build but i'm going for the best of the best
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Please make sure you reinforce your frame really well. Those engines have enough horsepower to turn a regular bicycle frame into a twisted piece of scrap metal.
First that video is super sik \m/ I saw it before and since then I've been eyeing a small dirtbike for sale in my neighborhood. My only concern is as much power as these things make I'd be scared to put it on a bicycle 
ill be watching this thread close and if all works out I may do something similar on my next build \m/
Till then I'm happy with the ht I have strapped to my cruiser yeah acceleration is super slow but I have modded the crap out of the motor with more to come to try and improve this. Just for the record I'm on engine #4 in my quest for more power from the ht. those things are fragile in comparison to a dirtbike engine
ill be watching this thread close and if all works out I may do something similar on my next build \m/ Till then I'm happy with the ht I have strapped to my cruiser
yeah acceleration is super slow but I have modded the crap out of the motor with more to come to try and improve this. Just for the record I'm on engine #4 in my quest for more power from the ht. those things are fragile in comparison to a dirtbike engine
I have gone through some of those H.T. motors.. yeah they are fragile indeed. lol
Sky is the limit man! There are tons of different brand motors out there just waiting for the picking!
Sky is the limit man! There are tons of different brand motors out there just waiting for the picking!
Don't wait for me, I am not going to start this till next summer, just putting my idea out there. I will find an old Schwinn and have mounts welded to all 3 tubes so there will be no torque on the frame.
im in no hurry on a build like this one - i have my ht equipped cranny to keep me busy till i come across a donor that i dont mind forking out the skrilla for \m/
Why are you guys looking for a used pit bike? They sell these engines everywhere. I want a 50cc version to stay legal. I'd go to 70's but the 50 would be much easier to fit.
http://tboltusa.com/store/ssr-50cc-engine-p-1077.html
Internal transmission for hills or top speed, decent power (more than ht for sure), and reliable! I'd love to see more bikes use these engines. They look and sound great
http://tboltusa.com/store/ssr-50cc-engine-p-1077.html
Internal transmission for hills or top speed, decent power (more than ht for sure), and reliable! I'd love to see more bikes use these engines. They look and sound great
My problem is they just don't sit right. I am not fond of the head angle. I was also looking into the two strokes mentioned by YGM. If the price is right that will be a build I will do.
I agree with you Rocky_Motor, these engines are everywhere!Why are you guys looking for a used pit bike? They sell these engines everywhere. I want a 50cc version to stay legal. I'd go to 70's but the 50 would be much easier to fit.
http://tboltusa.com/store/ssr-50cc-engine-p-1077.html
Internal transmission for hills or top speed, decent power (more than ht for sure), and reliable! I'd love to see more bikes use these engines. They look and sound great
HighRPMRacer.com sells these engines for about $139.00, they don't come with carb wiring harness and other parts but the price is right.
Here's the Link: Note: The price went up so I setup a wholesale account with Fancys Scooters buy the 49.7cc ( 50cc ) mini chopper complete $399.00 has it all if this is what you want to use for Motorizing you Bicycle / Stretch Cruiser / Limo Cruiser / Chopper / Low Rider Bicycle.
http://www.highrpmracer.com/chinese-engines-70cc-engine-complete-full-auto-no-reverse-p-13279.html
Here's the Link to their Wholesale page:
http://www.fancyscooters.com/fslistm.asp?list=wa1
Retail Price for this Mini Chopper is $679.00, see direct link below:
http://www.fancyscooters.com/item00187-peace-49cc-8000HD-chopper-harley-davidsion-style.html
Peace Mini Chopper (50cc Semi-automatic) Remember if you can setup a wholesale account with this company, you'll only pay $399.00 plus shipping!
GS-101 In Stock
Quantity Prices,
1-5 $399.00
6-11 $399.00
12-17 $399.00
18-29 $399.00
30-99 $399.00
If you haven't yet seen the thread alternate 50cc 4-stroke started by BarelyAwake, you can click on the link below in my signature!
C.H.
I've rode a bike with a semi auto, they are very finicky. I would choose a manual. They clunk in gear and are difficult to adjust. You can pick up a used 65 for less than 600 if you look long enough, especially in California, the motocross capital of the world. It would mount up very easily. I calculated the power to weight ratio, as long as bike+rider is less than 300lbs, you will be able to accelerate faster than a Kawasaki ninja 250. They are tame bikes, but to have a motorized bike faster than a motorcycle is pretty cool.I think you should be able to build a bike way under 100lbs, those little 65's are about 130 with full suspension and heavy duty components everywhere to withstand crashes and huge jumps. The engine probably weighs 40lbs or less. Case reed, no exhaust port control like bigger bikes so the power band is very snappy, I've riden one and it's a rush. My 125 is much smoother because of the "Honda Power Port" which raises and lowers the port ceiling for different rpm. It still has no bottom end power, same with a 65. My only concern is how to shift. I'm thinking maybe a lever near your knees so you can just tap it with one knee to shift up, and the other to go down. Or a thumb shifter on the bars, but the shifting on dirt bikes would be a little stiff for hand operation. I never understood a stick shift on a motorcycle, you have to take a hand off either the clutch or throttle to shift? No good for racing, or beating the blue haired woman in her Volvo at a stop sign race. 
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As far as I know, you shift by pushing up on a lever with your left foot to go up, or down to shift down. Often 1st gear is below neutral, and the other 4 are above neutral.
Do you guys know where to find the dimensions of a 50cc? or bigger so long as the engine is no bigger. I'd like to see if any of these will fit in the bikes I have
Do you guys know where to find the dimensions of a 50cc? or bigger so long as the engine is no bigger. I'd like to see if any of these will fit in the bikes I have
Are you thinking about like a 50cc dirt bike engine? As long as the cylinder is vertical it should fit in a large mountain bike or cruiser easily. The horizontal engines may not fit, idk. As far as shifting, yes I know how motorcycle shifters work but on a bike with pedals, that wouldn't work. I was thinking about attaching a cable to the shift lever so I could use another method to control it.
I'm not so sure about that. The Motopeds seem to be able to shift and they have pedals
I am currently seeking for an engine which shifts as well. I have been thinking about purchasing a used yz-80, and converting it to a motorbike, but the problem is I like my engines new. That way, I know everything about them. The problem has been finding a new multispeed 80cc engine. But definitely, you are not the only one considering a project like this. My morini is wicked fast, but its so much fun building the things and creating something even way more beastlier. Im just waiting on my bonus from work, and will start creating an 85 mph bicycle, hahaha. 85 mph you ask? 70 is attainable on a morini, all stock.
Nothing wrong with used engines, the big brands last a long time. Just do a compression test and test ride. You will have to buy a new bike to get a new engine, idk if you want to do that. Also, if you can fit a 125 in your bike, I would do it because 125s have variable exhaust ports that smooth out the power band. You will need a super strong rear wheel.
