So my friend and I are debating. We are modding a razor electric kids dirt bike. We are going to swap it for a gas engine, but that’s where the issue comes up. We can either buy a cheap 2-stroke lawnmower and snag the engine which is about 25-30 cc, or we can put on a Honda gx50 4-stroke which is about 350 dollars. Would they make near the same power if they can go the same rpm? Total noob question. All I know is that 4-stroke as 2x (50%) less efficient so assuming they are built for the same rpm, ccs won’t matter? Thanks.
50cc 4-stroke vs. 28cc 2-stroke
- Thread starter Barîb
- Start date
madprofessor
"Loose Cannon Creations"
Don't be misled into believing that because a 4-stroke only fires a compression stroke every other revolution of the motor that it's only half as efficient. If that was true all the cars and trucks in America would have 2-stroke motors.
Remember, for a horizontal axle (dirt bike, gokart, ATV, monster truck, unicycle) you need a horizontal shaft engine, not a lawnmower vertical.
Really considering a 4-stroke 50cc engine for $350? How about a 4-stroke 212cc for $150? Good ole Harbor Freight................
6.5 HP (212cc) OHV Horizontal Shaft Gas Engine, EPA (harborfreight.com)
EDIT NOTE: Basically all the 1200' long oil supertankers with 120,000hp. engines out there on the ocean actually do have 2-stroke engines. Running flat out they only spin a couple of hundred rpm.
Remember, for a horizontal axle (dirt bike, gokart, ATV, monster truck, unicycle) you need a horizontal shaft engine, not a lawnmower vertical.
Really considering a 4-stroke 50cc engine for $350? How about a 4-stroke 212cc for $150? Good ole Harbor Freight................
6.5 HP (212cc) OHV Horizontal Shaft Gas Engine, EPA (harborfreight.com)
EDIT NOTE: Basically all the 1200' long oil supertankers with 120,000hp. engines out there on the ocean actually do have 2-stroke engines. Running flat out they only spin a couple of hundred rpm.
It's really not about the output, more about how small we can make the engine, I run a HF 212 in my go kart, and a HF 79cc in my motorized bicycle, but we need something, smaller and lighter, closer to a dirt bike engine and further from log splitter. The problem of course is breaking the bank buying a 2,000 dollar engine. I say that after asking about a 350 dollar 50cc engine, but still. Any ideas?
madprofessor
"Loose Cannon Creations"
This Lifan 3hp., 4-stroke, 79cc, industrial engine lists its dimensions as 13" x 12" x 16" (probably the box size) at only 4.7 lbs. ???, and the money's not bad at $135 with free shipping. Lists a 11-tooth clutch for it at $22, and a #35 chain at $10 for a 3' length. Can be on your doorstep this coming Tuesday.................Amazon.com: Lifan LF152F-3Q 3 HP 79cc 4-Stroke OHV Industrial Grade Gas Engine with 18mm Keyway Shaft, Recoil Start and Universal Mounting Bolt : Patio, Lawn & Garden
EDIT: Found it on another site where it states a reasonable weight, 22.5 lbs. .................Horizontal Shaft Gas Engine LIFAN 5/8 in. 3 HP 79cc OHV Recoil Start Quieter | eBay
EDIT: Found it on another site where it states a reasonable weight, 22.5 lbs. .................Horizontal Shaft Gas Engine LIFAN 5/8 in. 3 HP 79cc OHV Recoil Start Quieter | eBay
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Karts of Kaos
the many mowers guy
where are you going to get a two strake lawn mower? i know of lawnboys, but in my experience there not that common
Flyinhillbilly
The great cornholio
You can buy a motorized bicycle kit for about $100. I have one and plan on using it on a small electric quad.
I e ridden them on bicycles and they’re not too bad, plus it has a clutch just like a real dirt bike.
I e ridden them on bicycles and they’re not too bad, plus it has a clutch just like a real dirt bike.
Yes, I've seen those, and believe me when I was building my motorized bicycle, I considered buying one, but from what I've seen, they're just too unreliable for my needs. I've done what I can only explain as extensive research without actually buying one, and I just can't trust them. Also the u-bolts mounts will not work for what I'm building. I'll try rebuilding this husqvarna first and keep that as an alternative.