So ive sourced a couple engines but have no clue on what sprocket to use for a 26" bike tire or what kind of chain to use. The motors are 50cc each one is a 2 stroke the other a four but like i say i have no clue where to go from there. The bike is a huffy cruiser bike with 26" wheels
So this is my absolute first build and i literally have about the tightest budget you could have
- Thread starter Jaquiline
- Start date
Venice Motor Bikes
Custom Builder / Dealer/Los Angeles
If you buy a complete engine kit, they come with the correct size sprocket.
The problem is i cant afford a full kit so im scavanging parts from either a child sized dirt bike or a 50cc four wheeler
Venice Motor Bikes
Custom Builder / Dealer/Los Angeles
Trust me... In the long run, it'll be way cheaper to just buy the complete kit!!
Im trying to get something going until i can upgrade to an actual kit sadly things are that tight right now
Venice Motor Bikes
Custom Builder / Dealer/Los Angeles
Good luck!!!
To answer your original question.... A 44t rear sprocket will work well with both engines.
To answer your original question.... A 44t rear sprocket will work well with both engines.
Thank you anything for a chain?
junglepig
Member
Tractor supply Company sell #41 chain that is better than the 415 chain in the kits.
But seriously, you can get a 50cc 2-stroke kit from eBay for under $100. That is the low budget way to go.
All you'll need from there is some better nuts and bolts to assemble it with and you're good to go (sort of.)
(You'll easily sink $100 into chains, sprockets, controls, etc. that will come with the kit.)
Sort of? Whats it missing?
junglepig
Member
This will get you rolling. There are some upgrades that many people find important or vital, like replacing the "rag joint" sprocket mount with a CNC mount, and replacing the chain tensioner with a much better version. Those are things you can do if you find you want to after the build. But those two alone will set you back at least $60 more. The kit + some decent nuts and bolts to replace the crappy low-grade steel ones that comes with the kits is enough to make that Huffy fly down the road. And you can upgrade other parts as you desire.
Seriously, use non-Chinese hardware for the rag joint and motor and tensioner mounts at a minimum.
Seriously, use non-Chinese hardware for the rag joint and motor and tensioner mounts at a minimum.
Ok what are you calling rag joints? Remember i know nothing about this kind of thing other than tuning the motor itself lol
junglepig
Member
No problem.
You might want to go to youtube and watch a video of someone installing one of these chinese kits. They all come with a mount for the new rear sprocket that is 2 pieces of thick, tire-like rubber rings that sandwich the spokes around the left side of your back wheel. A set of 9 bolts feed through the sprocket and then through the rubber doughnut-spoke-doughnut sandwich to attach the sprocket to the left side of the rear wheel.(there's also 3 metal plates that form a circle along the rubber on the inside where the nuts go.)
This is called a "rag joint."
A better mount, available separately for 40+ bucks, is made of metal and bolts directly to your sprocket and clamps to your hub, which is way better than the rag joint for a number of reasons.
If you're patient, mechanically inclined, and use good hardware you can successfully use the rag joint. It just absolutely must be true and secure.
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Ok so how well do the chinese motors run out of the box? I mean yeah i can tune it, but that going to take longer than i really have. Im trying to do this in like a day or two at the most so if i can get away with running it as is out of the box i may do it but if it needs tuned before hand i may just shove the motor out of the dirt bike into it and try to rig up something without the kit. Im pretty mechanical so custom work isnt beyond me it would just look like a horror show lol
junglepig
Member
They're new and really need breaking in.
You sound like you can easily install it in a day.
If you go super low budget like I do and buy from an eBay seller, no one on this side of the Pacific will have looked at the motor, so you're gonna want to inspect it as close as you are comfortable taking it apart and doing. Like pulling the head and taking a quick look inside the cylinder to clean it up and prelube it a little. And checking that the rest of the bolts are tight, Woodruff keys are installed, etc. And retorque the head bolts or cap nuts.
But if you can do a custom build in a day or so, you're way way better than me (easily done, lol)
But yeah, chances are it's gonna run fine as soon as you turn it over.
(And hey, I'm a NOOB too, but I've finished a build, obsessed and read and watched a lot of videos, and shopped every supplier and distributor. Like I said, obsessed. I'm answering your questions when I think I really know the answers. And if I get off-base I'm sure someone will correct me on your behalf. These folks are very helpful and knowledgeable here.)
You sound like you can easily install it in a day.
If you go super low budget like I do and buy from an eBay seller, no one on this side of the Pacific will have looked at the motor, so you're gonna want to inspect it as close as you are comfortable taking it apart and doing. Like pulling the head and taking a quick look inside the cylinder to clean it up and prelube it a little. And checking that the rest of the bolts are tight, Woodruff keys are installed, etc. And retorque the head bolts or cap nuts.
But if you can do a custom build in a day or so, you're way way better than me (easily done, lol)
But yeah, chances are it's gonna run fine as soon as you turn it over.
(And hey, I'm a NOOB too, but I've finished a build, obsessed and read and watched a lot of videos, and shopped every supplier and distributor. Like I said, obsessed. I'm answering your questions when I think I really know the answers. And if I get off-base I'm sure someone will correct me on your behalf. These folks are very helpful and knowledgeable here.)
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Lol by horror show i mean like jerryrigging a chainsaw in it and having zipties everywhere lol. But on a serious note any tricks you might suggest when it comes time to get the work done
junglepig
Member
Somebody here will help I'm sure.
If you're on a budget AND a tight time frame, I'd say a kit is the way to go.
The kit has solved almost all your problems in the most economical way possible.
And even so, you will probably have some challenges that will require your custom work skills since all bikes are different and these are "universal". But at least you can pretty easily get your clutch and throttle linkages done up, as well as a decent way to link the drive gear to a sprocket (and still be able to use your pedals). You'll have a fuel tank without zip-tying a Coleman Fuel can to the top bar (LOL), etc.
Good Luck!
If you're on a budget AND a tight time frame, I'd say a kit is the way to go.
The kit has solved almost all your problems in the most economical way possible.
And even so, you will probably have some challenges that will require your custom work skills since all bikes are different and these are "universal". But at least you can pretty easily get your clutch and throttle linkages done up, as well as a decent way to link the drive gear to a sprocket (and still be able to use your pedals). You'll have a fuel tank without zip-tying a Coleman Fuel can to the top bar (LOL), etc.
Good Luck!
Lol the coleman can is too high class i roll with a 2 liter coke bottle lol nah i was basically going to cannibalize the dirt bike for basically everything of use to have to buy as few parts as possible
junglepig
Member
I see. That's more viable. I thought you just had a couple of engines, a bike, and were going from there.
So is are the engines off mini-bikes? If so, you're going to need to do custom mounting for them - they won't bolt up to a bicycle frame in a very useful way.
I'd say get familiar with the kits, see how they go together, and then consider what you have on hand and just how you plan to transmit power to that back wheel. There are lots of options. You could just do a friction roller mount to the back tire. That's probably your fast, budget build right there.
In fact, I probably made a lot of assumptions.
Maybe describe more of your goals to us.
The thing is the huffy has that whole rear fender and id like to keep the same style but its also got coaster brakes on it. So how could i possibly convert it to rim brakes or disc brakes?
junglepig
Member
You can install rim or disc brakes if you want. You can keep the coaster brake. You will want something in addition to the coaster brake for safety.
I may be missing what you are asking. I'm getting sleepy.
I thought I'd share this giant photo of an automotive "rag joint". It's from a steering column on something. Probably an old Chevy. Anyway, the name rag joint comes from the fibers visible in layers at the edges. This is what the kits use, but they have nine holes, and often appear to have been sawed down the (almost) center to make two thinner doughnuts.
These joints are used on steering columns, pto shafts, some driveshafts (instead of a universal joint). I'm not sure exactly what original application got picked up to become the Chinese Motorized Bicycle Sprocket mount, LOL. But it is clever.
I may be missing what you are asking. I'm getting sleepy.
I thought I'd share this giant photo of an automotive "rag joint". It's from a steering column on something. Probably an old Chevy. Anyway, the name rag joint comes from the fibers visible in layers at the edges. This is what the kits use, but they have nine holes, and often appear to have been sawed down the (almost) center to make two thinner doughnuts.
These joints are used on steering columns, pto shafts, some driveshafts (instead of a universal joint). I'm not sure exactly what original application got picked up to become the Chinese Motorized Bicycle Sprocket mount, LOL. But it is clever.