I'm thinking 60:15
Mini monster Moto predator swap
- Thread starter Eemownz
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I'm thinking 60:15
That is still steep, and you will have very little low end torque. Give it a try though if you have the sprockets and see what it is like
I have 75:12 right now, what gear ratio do you recommend?
bob58o
SuckSqueezeBangBlow
Are you trying to set a land speed record?
Where do you drive it?
In a Parking Lot?
In a neighborhood?
Stop and go?
5 miles WOT down a country road?
I still think 75:16 would be alright.
You can keep the rear sprocket and only need to change the clutch sprocket.
The offer clutches with up to 25T so I don't see a need to change the rear sprocket at all.
The more teeth on the clutch sprocket (or the less teeth on the rear sprocket) means it is going to be harder on the clutch. When geared for a high top speed, stop and go riding will burn up a clutch.
So it depends on where you ride, how much space you have, and how you drive.
If you don't stop often and have 1/2 mile straight aways - you might be able to gear 75:18 and hit 50 mph. Probably not without modifications.
With 14" Tires on a little minibike with a clutch, 5:1 gear ratio will be ok for most driving conditions. Good amount of stop and go. Some uphill driving....
4:1 Gear ratio will have 36% less torque than you have now. It will not as good for stop and go. Not as good at climbing hills. Less acceleration. Better top speed, but takes more time and distance to get to that top speed.
If geared for a high top speed on a short course with lots of stops and turns, the max MPH achieved will probably be lower.
The more I think about it, the more I like 75:16.
75:16 is a good option.
At least until you tell us more about what your intentions are.
A 3hp engine has around 3.5 lb ft max torque.
A 212 has around 8.1 lb ft max torque.
Theoretically you could put a 28T sprocket on the clutch and have the same wheel torque at clutch engagement as you had with the 80cc engine. Problem is that the clutch engages at 1800 RPM. If you had 75:28, then at 1800 RPM you should be already be moving 28mph. With 75:12 you should be moving 12mph at 1800 RPM (when the clutch engages) which is a much healthier MPH for clutch engagement.
Where do you drive it?
In a Parking Lot?
In a neighborhood?
Stop and go?
5 miles WOT down a country road?
I still think 75:16 would be alright.
You can keep the rear sprocket and only need to change the clutch sprocket.
The offer clutches with up to 25T so I don't see a need to change the rear sprocket at all.
The more teeth on the clutch sprocket (or the less teeth on the rear sprocket) means it is going to be harder on the clutch. When geared for a high top speed, stop and go riding will burn up a clutch.
So it depends on where you ride, how much space you have, and how you drive.
If you don't stop often and have 1/2 mile straight aways - you might be able to gear 75:18 and hit 50 mph. Probably not without modifications.
With 14" Tires on a little minibike with a clutch, 5:1 gear ratio will be ok for most driving conditions. Good amount of stop and go. Some uphill driving....
4:1 Gear ratio will have 36% less torque than you have now. It will not as good for stop and go. Not as good at climbing hills. Less acceleration. Better top speed, but takes more time and distance to get to that top speed.
If geared for a high top speed on a short course with lots of stops and turns, the max MPH achieved will probably be lower.
The more I think about it, the more I like 75:16.
75:16 is a good option.
At least until you tell us more about what your intentions are.
A 3hp engine has around 3.5 lb ft max torque.
A 212 has around 8.1 lb ft max torque.
Theoretically you could put a 28T sprocket on the clutch and have the same wheel torque at clutch engagement as you had with the 80cc engine. Problem is that the clutch engages at 1800 RPM. If you had 75:28, then at 1800 RPM you should be already be moving 28mph. With 75:12 you should be moving 12mph at 1800 RPM (when the clutch engages) which is a much healthier MPH for clutch engagement.
bob58o
SuckSqueezeBangBlow
If you want 50mph, gear 75:18 and see if you can get up to 5000 RPM.
If you can't get 50mph, it will be because you need more HP. 75:18 with 14" tires will at least give you a shot at 50mph.
But like you've been warned already, that gearing is not optimal for stop and go - so proceed at will. You don't seem to like the safe answers, so here's the answer you want.
75:18 is what you need for a shot at 50mph around 5000 RPM.
If you can't get 50mph, it will be because you need more HP. 75:18 with 14" tires will at least give you a shot at 50mph.
But like you've been warned already, that gearing is not optimal for stop and go - so proceed at will. You don't seem to like the safe answers, so here's the answer you want.
75:18 is what you need for a shot at 50mph around 5000 RPM.
mckutzy
Well-known member
you dont have that option... either or...
Where are you getting these other sprockets for you clutch???.... the average clutch just has 12t for #35 chain and 10t for #40 chain.... there isnt any other options....
Or do you have a jackshaft???
And for one thing....
Pics of this bike...
Where are you getting these other sprockets for you clutch???.... the average clutch just has 12t for #35 chain and 10t for #40 chain.... there isnt any other options....
Or do you have a jackshaft???
And for one thing....
Pics of this bike...
bob58o
SuckSqueezeBangBlow
OMB has 3/4 clutch with a sprocket up to 25T that the OP linked somewhere on the thread.
https://www.ombwarehouse.com/max-torque-box-stock-clone-clutch-3-4-35-10t.html
The solution is a Torque Converter, which will allow you to gear faster, use for stop and go- but it is going to probably Wheelie, which you don’t want.
https://www.ombwarehouse.com/max-torque-box-stock-clone-clutch-3-4-35-10t.html
The solution is a Torque Converter, which will allow you to gear faster, use for stop and go- but it is going to probably Wheelie, which you don’t want.
bob58o
SuckSqueezeBangBlow
Well, if you are willing to accept the wheelies....
Then a TC will be much better for you IF THE Torque Coverter FITS!
There is no 18T clutch when using a TC.
18T clutch OR torque converter.
If you use a torque converter and use a 4.2:1 sprocket ratio, you will still have the gearing to reach 50mph (if the engine has the power) and you will have the low end for stop and go. When the TC engages at 2200 RPM, the gear ratio will be 11.2:1 (watch for the wheelies), and the bike would only be moving 8mph at 2200 RPM with 11.2:1 Gear ratio. As the TC shifts into higher gear, you will get to 3.8:1 gear ratio. This will probably get you close to 50mph. The actual gearing is for 55mph at 5000 RPM. I'm guessing uou will probably reach max speed/rpm under 50mph/4500 RPM (just guessing, I don't know how much you weigh, would still just be guessing)... But then you can upgrade the engine and get more power at higher RPMs and reach higher speeds and more RPMs.
Most torque converters use a 5/8" Jackshaft. There is an 18T #35 pitch 5/8" bore sprocket, but it is a B type sprocket (instead of the C type sprocket that comes on the TC). It can be made to work, but you need to make sure you have the alignment correct. I've used a B type sprocket on a TC kit before, but don't remember exactly how I spaced things out. It is not a direct swap.
Otherwise the kit will come with a 12T, #35, 5/8" Bore, C type sprocket. And you would just need to get a 50T sprocket to match the bolt pattern you have.
The TC kits used to be under $55, so shop around.
https://www.ebay.com/itm/COMET-TORQ...685830&hash=item3d2b671fc6:g:RnYAAOSwcUBYK~nc
http://www.monsterscooterparts.com/...UDNJVqp7tkagiBjw5WJVIW3_GzcX5CcsaApm1EALw_wcB
---------- Post added at 10:56 PM ---------- Previous post was at 10:39 PM ----------
My minibike has smaller tires (13" vs your 14" - smaller tires = more torque) and a TC which engages with a 16.9:1 Gear Ratio. I have to be careful if I don't want the front to pull up, but I can keep the wheel down if I want. So you should be able to keep the wheel down.
Another very good question is "Does a TC kit fit on that bike with that engine?"
IIRC it is very tight just getting the engine in there. Anybody have one of these with a Torque Converter?
Then a TC will be much better for you IF THE Torque Coverter FITS!
There is no 18T clutch when using a TC.
18T clutch OR torque converter.
If you use a torque converter and use a 4.2:1 sprocket ratio, you will still have the gearing to reach 50mph (if the engine has the power) and you will have the low end for stop and go. When the TC engages at 2200 RPM, the gear ratio will be 11.2:1 (watch for the wheelies), and the bike would only be moving 8mph at 2200 RPM with 11.2:1 Gear ratio. As the TC shifts into higher gear, you will get to 3.8:1 gear ratio. This will probably get you close to 50mph. The actual gearing is for 55mph at 5000 RPM. I'm guessing uou will probably reach max speed/rpm under 50mph/4500 RPM (just guessing, I don't know how much you weigh, would still just be guessing)... But then you can upgrade the engine and get more power at higher RPMs and reach higher speeds and more RPMs.
Most torque converters use a 5/8" Jackshaft. There is an 18T #35 pitch 5/8" bore sprocket, but it is a B type sprocket (instead of the C type sprocket that comes on the TC). It can be made to work, but you need to make sure you have the alignment correct. I've used a B type sprocket on a TC kit before, but don't remember exactly how I spaced things out. It is not a direct swap.
Otherwise the kit will come with a 12T, #35, 5/8" Bore, C type sprocket. And you would just need to get a 50T sprocket to match the bolt pattern you have.
The TC kits used to be under $55, so shop around.
https://www.ebay.com/itm/COMET-TORQ...685830&hash=item3d2b671fc6:g:RnYAAOSwcUBYK~nc
http://www.monsterscooterparts.com/...UDNJVqp7tkagiBjw5WJVIW3_GzcX5CcsaApm1EALw_wcB
---------- Post added at 10:56 PM ---------- Previous post was at 10:39 PM ----------
My minibike has smaller tires (13" vs your 14" - smaller tires = more torque) and a TC which engages with a 16.9:1 Gear Ratio. I have to be careful if I don't want the front to pull up, but I can keep the wheel down if I want. So you should be able to keep the wheel down.
Another very good question is "Does a TC kit fit on that bike with that engine?"
IIRC it is very tight just getting the engine in there. Anybody have one of these with a Torque Converter?
You cannot have it both ways. It just doesn't work like that
mindymogul
Mistress of Destruction
In the simplest way of explaining things... What you want is impossible. Once people start breaking out the math that means they KNOW what they're talking about. There's no other way around it. And again, Torque Converter OR Centrifugal Clutch. There is no "ifs, ands, or buts" about it. One or the other. Just like when you wanted those 2 candy bars but you had to choose one when you were at the store when you were little. Same concept.
My bad, Im Just getting into this stuff and I thought that clutch and tc went together
---------- Post added at 10:00 AM ---------- Previous post was at 09:59 AM ----------
I have seen a YouTube video with one on, I believe a little modification was needed
---------- Post added at 10:00 AM ---------- Previous post was at 09:59 AM ----------
I have seen a YouTube video with one on, I believe a little modification was needed
mckutzy
Well-known member
10t is the smallest they come with...
Rear sprocket I mean
mindymogul
Mistress of Destruction
TC: 12t #35
AS: 72t #35 @ 6.1
or
TC: 10t #40/41
AS: 42t #40/41 @ 4.2
You're still gonna have slippage no matter what way you look at it with your "demands" but if you learn to not lean on it you can keep it on the ground and keep high speed.
AS: 72t #35 @ 6.1
or
TC: 10t #40/41
AS: 42t #40/41 @ 4.2
You're still gonna have slippage no matter what way you look at it with your "demands" but if you learn to not lean on it you can keep it on the ground and keep high speed.
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