Best way to mount an A80 kit to my new bike :)
- Thread starter Pcain
- Start date
Bikeguy Joe
Godfather of Motorized Bicycles
A80? Is that an in frame "80cc" kit from china? If so, it's gonna be tight, but I have seen it done
Yeah the A80/66cc china kit. I have seen a few pics but I'm not sure if they are 48cc, but it looks like a snug fit.
dragray
New Member
First off, that's a pretty cool looking bike...where did you get it?
as for your question.....Yes it can be done but be prepared to modify and make parts.
The biggest issue will be the intake manifold / carb. because you may not have the clearance between the seat tube and the air filter. you can either shorten the intake tube, or buy an off-set intake tube. But i'm pretty sure that a stock 66 c.c. intake tube is too long and the carb won't clear the seat post tube.
You'll have to bend the exhaust because it may end up too close to the ground.(if you run the stock exhaust anyway).
you'll have to shorten your clutch and throttle cables (unless you don't mind a bunch of extra cable strung all over the place.)
you'll have to shorten your engine chain quite a bit.
I had to make a steel spacer plate to go between the rear engine mount and the engine to move the mount closer to the frame. You need to get the engine at the correct angle, and in order for me to get that correct angle, i had to make the spacer plate to move the rear engine mount out slightly. If i remember right, the spacer I made is approx 1/8" thick.
If your engine is it at too much of a forward angle, your carb won't be level, and you're float bowl will run out of gas during full throttle runs.
once you get the engine, and you mock it up in the frame, you'll see what i mean....unless your frame tubes are at different angles than mine.
If you are going to run a 44 tooth rear sprocket, be prepared to only get about 20 mph out of the bike when it's done. The 20" wheels makes the gear ratio lower (less top speed). I'm running a 41 tooth on mine and i'm getting right at about 25-28 mph out of it.
The best option i think is to go with a 36 tooth sprocket to keep the rpms down while crusing at 15-20 mph. a 36 tooth may allow you to get up to 30-32 mph top speeds.
BUT, rider weight plays a roll in this as well.
here's my 20" bike, but if you notice, mine does not have an intake manifold. My carb is mounted right to the cylinder, which gives me lots of clearance.
My engine is a 49 c.c. china 2 stroke, and i'm not sure if they still make them this way (without the intake manifold). Mine has a totally different style carb on it than the normal n.t. carb, because the carb is mounted to 2 studs that screw into the cylinder.
here's a closeup of the carb on my engine...no intake tube, no clearance issues.
as for your question.....Yes it can be done but be prepared to modify and make parts.
The biggest issue will be the intake manifold / carb. because you may not have the clearance between the seat tube and the air filter. you can either shorten the intake tube, or buy an off-set intake tube. But i'm pretty sure that a stock 66 c.c. intake tube is too long and the carb won't clear the seat post tube.
You'll have to bend the exhaust because it may end up too close to the ground.(if you run the stock exhaust anyway).
you'll have to shorten your clutch and throttle cables (unless you don't mind a bunch of extra cable strung all over the place.)
you'll have to shorten your engine chain quite a bit.
I had to make a steel spacer plate to go between the rear engine mount and the engine to move the mount closer to the frame. You need to get the engine at the correct angle, and in order for me to get that correct angle, i had to make the spacer plate to move the rear engine mount out slightly. If i remember right, the spacer I made is approx 1/8" thick.
If your engine is it at too much of a forward angle, your carb won't be level, and you're float bowl will run out of gas during full throttle runs.
once you get the engine, and you mock it up in the frame, you'll see what i mean....unless your frame tubes are at different angles than mine.
If you are going to run a 44 tooth rear sprocket, be prepared to only get about 20 mph out of the bike when it's done. The 20" wheels makes the gear ratio lower (less top speed). I'm running a 41 tooth on mine and i'm getting right at about 25-28 mph out of it.
The best option i think is to go with a 36 tooth sprocket to keep the rpms down while crusing at 15-20 mph. a 36 tooth may allow you to get up to 30-32 mph top speeds.
BUT, rider weight plays a roll in this as well.
here's my 20" bike, but if you notice, mine does not have an intake manifold. My carb is mounted right to the cylinder, which gives me lots of clearance.
My engine is a 49 c.c. china 2 stroke, and i'm not sure if they still make them this way (without the intake manifold). Mine has a totally different style carb on it than the normal n.t. carb, because the carb is mounted to 2 studs that screw into the cylinder.
here's a closeup of the carb on my engine...no intake tube, no clearance issues.
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Bikeguy Joe
Godfather of Motorized Bicycles
Great post DR!
.
.
First off, that's a pretty cool looking bike...where did you get it?
as for your question.....Yes it can be done but be prepared to modify and make parts.
The biggest issue will be the intake manifold / carb. because you may not have the clearance between the seat tube and the air filter. you can either shorten the intake tube, or buy an off-set intake tube. But i'm pretty sure that a stock 66 c.c. intake tube is too long and the carb won't clear the seat post tube.
You'll have to bend the exhaust because it may end up too close to the ground.(if you run the stock exhaust anyway).
you'll have to shorten your clutch and throttle cables (unless you don't mind a bunch of extra cable strung all over the place.)
you'll have to shorten your engine chain quite a bit.
I had to make a steel spacer plate to go between the rear engine mount and the engine to move the mount closer to the frame. You need to get the engine at the correct angle, and in order for me to get that correct angle, i had to make the spacer plate to move the rear engine mount out slightly. If i remember right, the spacer I made is approx 1/8" thick.
If your engine is it at too much of a forward angle, your carb won't be level, and you're float bowl will run out of gas during full throttle runs.
once you get the engine, and you mock it up in the frame, you'll see what i mean....unless your frame tubes are at different angles than mine.
If you are going to run a 44 tooth rear sprocket, be prepared to only get about 20 mph out of the bike when it's done. The 20" wheels makes the gear ratio lower (less top speed). I'm running a 41 tooth on mine and i'm getting right at about 25-28 mph out of it.
The best option i think is to go with a 36 tooth sprocket to keep the rpms down while crusing at 15-20 mph. a 36 tooth may allow you to get up to 30-32 mph top speeds.
BUT, rider weight plays a roll in this as well.
here's my 20" bike, but if you notice, mine does not have an intake manifold. My carb is mounted right to the cylinder, which gives me lots of clearance.
My engine is a 49 c.c. china 2 stroke, and i'm not sure if they still make them this way (without the intake manifold). Mine has a totally different style carb on it than the normal n.t. carb, because the carb is mounted to 2 studs that screw into the cylinder.
here's a closeup of the carb on my engine...no intake tube, no clearance issues.
Wow, super informative. Much appreciate it.
I bought two of these at Big W. It is sort of like a K Mart. Brand new retail for $170, got them each for $98.
Your bike is sweet! I was thinking the height wold be an issue, never considered the intake... I have an intake manifold off an old 70cc pocket bike. I'm sure with a dremel I could make it work, otherwise I could do something similar to you, just use a solid thick gasket like material. I'll figure something out. Is the exhaust difficult to bend? Is there a process for this?
This a photo from the eBay ad. I'm a big guy, 6'3 240lbs so I hope it still carries me, otherwise I might have play around with sprockets.
dragray
New Member
well, bending the stock exhaust is pretty easy.
DO NOT try to bend it with it mounted to the engine because you will break the exhaust mounting studs on the cylinder.
when i first built this bike, i used the stock exhaust and the bike had a totally different look to it.
To bend the stock exhaust, put it on the engine and tighten the nuts to get the flange against the engine where it needs to be.
Then, figure out where you need to bend it.
take it off of the engine, and put the exhaust pipe into a vice using 2 peices of wood to hold it.
Heat the area of the pipe where you want to bend it (i just used a propane torch).
then i put a pipe in the flange end of the pipe, and pulled it until i got it bent where i needed it to be.
with out bending it, the muffler was really close to the ground.
if you look at this picture of my bike, you will see the the engine is at a very forward angle (which i changed later). having the engine at this forward angle made the carb unlevel....and this is when the float bowl would run out of fuel during w.o.t. runs. during the re-build, I also flipped the head around 180 degrees to put the spark plug towards the front of the engine for clearand between it and the top frame tube. here you see the plug angled to the rear of the engine.
This bike went through several different re-builds as i made changes along the way.
Also notice that in these pics., the throttle and clutch cables are at their stock lengths and were too long. There was a lot of excess cable strung all over the place. the wiring wasn't done cleanly in my opinion, so I changed all of that stuff to clean up the look of the bike.
I also re-located my cdi box so it was down under the engine, kind of hidden out of site.
You can replace the stock spark plug wire with an automotive one so you can make it any length you want to get the cdi box put somewhere other than right in the front of the lower frame tube (which is where most people mount them).
This will also help you hide some of the wiring to clean it up a bit.
so my bike went from being a lowrider to a drag bike. first built in 2009, changed a little in 2010, changed into a drag bike in 2012.
The exhaust that i have on it now is an expansion chamber made by skyhawk (sold by spooky tooth, but they are now out of business i think). I did have to bend the expansion chamber to get the outlet of the pipe where i wanted it. I also used stock muffler on the end of the expansion chamber but I modified the baffle for better flow.
DO NOT try to bend it with it mounted to the engine because you will break the exhaust mounting studs on the cylinder.
when i first built this bike, i used the stock exhaust and the bike had a totally different look to it.
To bend the stock exhaust, put it on the engine and tighten the nuts to get the flange against the engine where it needs to be.
Then, figure out where you need to bend it.
take it off of the engine, and put the exhaust pipe into a vice using 2 peices of wood to hold it.
Heat the area of the pipe where you want to bend it (i just used a propane torch).
then i put a pipe in the flange end of the pipe, and pulled it until i got it bent where i needed it to be.
with out bending it, the muffler was really close to the ground.
if you look at this picture of my bike, you will see the the engine is at a very forward angle (which i changed later). having the engine at this forward angle made the carb unlevel....and this is when the float bowl would run out of fuel during w.o.t. runs. during the re-build, I also flipped the head around 180 degrees to put the spark plug towards the front of the engine for clearand between it and the top frame tube. here you see the plug angled to the rear of the engine.
This bike went through several different re-builds as i made changes along the way.
Also notice that in these pics., the throttle and clutch cables are at their stock lengths and were too long. There was a lot of excess cable strung all over the place. the wiring wasn't done cleanly in my opinion, so I changed all of that stuff to clean up the look of the bike.
I also re-located my cdi box so it was down under the engine, kind of hidden out of site.
You can replace the stock spark plug wire with an automotive one so you can make it any length you want to get the cdi box put somewhere other than right in the front of the lower frame tube (which is where most people mount them).
This will also help you hide some of the wiring to clean it up a bit.
so my bike went from being a lowrider to a drag bike. first built in 2009, changed a little in 2010, changed into a drag bike in 2012.
The exhaust that i have on it now is an expansion chamber made by skyhawk (sold by spooky tooth, but they are now out of business i think). I did have to bend the expansion chamber to get the outlet of the pipe where i wanted it. I also used stock muffler on the end of the expansion chamber but I modified the baffle for better flow.
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dragray
New Member
no problem.
Most of all, take your time and don't rush it.
have you read any of the posts that talk about replacing the kit nuts, bolts and lockwashers with some better ones? the ones that come with these kits are VERY cheap. they will break and strip with very little effort.
spend some extra money at the hardware store and replace all of the nuts, bolts and lockwashers with some better quality ones (the ones that come in the bag in the kit).
also, buy some blue loc-tite, and use it on every nut & bolt.
don't buy regular nuts, get lock nuts that have the nylon inserts....and use loc-tite along with them.
also, another tip is to not use the push together wire connectors that come with the engine kit. do yourself a favor, and cut your wires to the right length, and then solder all of your connections....and cover them with heat shrink.
make sure that nothing is hooked to the white wire coming from the magneto.
just cut it off, and cap the end of it with heatshrink.
they say that you can hook a headlight to the white wire, but trust me, it won't work.
hooking anything to the white wire will steal power from the magneto and your engine won't run.
get yourself a good ngk b6hs spark plug and use it rather than cheap china plug that comes with the kit.
get yourself a good high flow air filter because the stock filter is nothing more than a thin peice of foam and it's very restrictive.
if you use the stock exhaust, you can modify the baffle plate inside of it for better flow (if you end up with the muffler that's screwed together rather than welded together).
there's also a little cateletic converter type thing inside the muffler that you can remove for even better flow...that is if you have the screw together muffler.
but your best bet is to end up getting an expansion chamber exhaust.
go for a kit that has an nt carb rather than a cns. the cns carbs are very tricky to get tuned right and the nt carbs are simple to tune, and they work great when tuned right.
but, all of that will come later, after you get it all together and running.
again, take your time....and have fun with it.
Most of all, take your time and don't rush it.
have you read any of the posts that talk about replacing the kit nuts, bolts and lockwashers with some better ones? the ones that come with these kits are VERY cheap. they will break and strip with very little effort.
spend some extra money at the hardware store and replace all of the nuts, bolts and lockwashers with some better quality ones (the ones that come in the bag in the kit).
also, buy some blue loc-tite, and use it on every nut & bolt.
don't buy regular nuts, get lock nuts that have the nylon inserts....and use loc-tite along with them.
also, another tip is to not use the push together wire connectors that come with the engine kit. do yourself a favor, and cut your wires to the right length, and then solder all of your connections....and cover them with heat shrink.
make sure that nothing is hooked to the white wire coming from the magneto.
just cut it off, and cap the end of it with heatshrink.
they say that you can hook a headlight to the white wire, but trust me, it won't work.
hooking anything to the white wire will steal power from the magneto and your engine won't run.
get yourself a good ngk b6hs spark plug and use it rather than cheap china plug that comes with the kit.
get yourself a good high flow air filter because the stock filter is nothing more than a thin peice of foam and it's very restrictive.
if you use the stock exhaust, you can modify the baffle plate inside of it for better flow (if you end up with the muffler that's screwed together rather than welded together).
there's also a little cateletic converter type thing inside the muffler that you can remove for even better flow...that is if you have the screw together muffler.
but your best bet is to end up getting an expansion chamber exhaust.
go for a kit that has an nt carb rather than a cns. the cns carbs are very tricky to get tuned right and the nt carbs are simple to tune, and they work great when tuned right.
but, all of that will come later, after you get it all together and running.
again, take your time....and have fun with it.
Cheers! My thought was to take all the nuts and bolts and hit up a hardware store before I even begin assembling it. Best type to get? I was going to get high tensile stainless bolts with nylon nuts as you mentioned. Also, where would I use the blue lock tite? I'm worried I might not be able to remove these bolts later if I use it?
dragray
New Member
You can just get grade 8 bolts. stainless is nice, but its actually weaker than steel. get blue loc tite & use it on the rear sprocket bolts, the engine mount nuts, and the exhaust nuts. blue loc tite is not permanent so the nuts will come back off fairly easy. red loc tite is permanent & you have to ue heat to break it loose.
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Awesome, thanks for clearing that up!
Now I'm trying to suss out ways of gold plating my rims. Maybe spray paint gold but not sold on the dull finish.
Bikeguy Joe
Godfather of Motorized Bicycles
Actually, you may want to go with grade 5 hardware....grade 8 is not the best for your application.