Speed estimate vintage engine
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B.M.800
TheBeal.
Depends on your gearing. You can be fast, or you can be quick.
Doc Sprocket
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Nowhere near enough info to go on, here.
An engine doesn't go fast- the vehicle does. Tell us about the vehicle. Type, size, weight, tire size, gearing, intended terrain and riding conditions, etc.
An engine doesn't go fast- the vehicle does. Tell us about the vehicle. Type, size, weight, tire size, gearing, intended terrain and riding conditions, etc.
B.M.800
TheBeal.
^^ Like he said, there are alot of things to consider.
If you want fast, your take off will be low, and you might aswell forget about hills. Possibly to a point where you will have to replace the clutch more often.
If you want fast, your take off will be low, and you might aswell forget about hills. Possibly to a point where you will have to replace the clutch more often.
I havent built a frame yet, so I plan to do something for the most speed. plan to have either all 10 inch tires or 10 inch in the front and 13 in the back. I have access to a HAAS mill so I plan to machine the drive sprocket and the clutch is 13 Tooth. I plan to drive it on either a field or road. Any thoughts to get the top speed out of this? I'm new to this, i'm planning a summer project.
Doc Sprocket
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Don't expect too much. It's a 3hp engine. to get the most out of it, design a frame that is as lightweight as you can possibly muster, without building a deathtrap. Keep tire size to a minimum, 10 or 11" max.
Some engine mods can be done like removing the governor, porting, aspiration, etc. But again, it's a 3hp engine.
FWIW- I believe the governor on that engine is pneumatic- removal does not even require opening up the engine, just 30 seconds with the blower housing off...
Some engine mods can be done like removing the governor, porting, aspiration, etc. But again, it's a 3hp engine.
FWIW- I believe the governor on that engine is pneumatic- removal does not even require opening up the engine, just 30 seconds with the blower housing off...
Doc Sprocket
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Ratios that high will result in a fried clutch, IF the engine even has enough oomph to fry it. Might just stall.
Doc Sprocket
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A fried clutch is a clutch that has fried. Gearing too high causes excessive clutch slippage, and that equals heat. Heat destroys clutches.
Regarding gearing, I don't know what two stories you're hearing, but there's only one "story". Gearing to a lower ratio results in more torque/acceleration, and less top speed. higher gearing sacrifices torque but results in higher speed. Gearing two high cooks your clutch, if the engine even has enough grunt to get it moving. For clarity, a LOW ratio is numerically higher (say 6:1) and a HIGH ratio is lower numerically (say 3:1). Therefore, 6:1 is a LOWER gear ratio than 3:1.
Regarding actual sprocket size- a small clutch sprocket and big axle sprocket results in a lower gear ratio, whereas a large clutch sprocket and small axle sprocket results in a high ratio.
Regarding gearing, I don't know what two stories you're hearing, but there's only one "story". Gearing to a lower ratio results in more torque/acceleration, and less top speed. higher gearing sacrifices torque but results in higher speed. Gearing two high cooks your clutch, if the engine even has enough grunt to get it moving. For clarity, a LOW ratio is numerically higher (say 6:1) and a HIGH ratio is lower numerically (say 3:1). Therefore, 6:1 is a LOWER gear ratio than 3:1.
Regarding actual sprocket size- a small clutch sprocket and big axle sprocket results in a lower gear ratio, whereas a large clutch sprocket and small axle sprocket results in a high ratio.
Doc Sprocket
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To avoid retyping multiple paragraphs, I'm going to merge this with your other thread.
Doc Sprocket
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For a high ratio, you want a larger clutch sprocket and smaller axle sprocket. And your kart probably won't move.
You see, ratios and speed are only theoretical. IF your engine does not have enough torque, you simply cannot reach the projected speed.
A little bit of friendly advice for you- forget gearing, it's too early. You need to gear for what you have, and right now you have nothing- other than a small, weak engine. You need to focus on a very small, very light frame, OR a bigger engine. Gearing comes later.
You see, ratios and speed are only theoretical. IF your engine does not have enough torque, you simply cannot reach the projected speed.
A little bit of friendly advice for you- forget gearing, it's too early. You need to gear for what you have, and right now you have nothing- other than a small, weak engine. You need to focus on a very small, very light frame, OR a bigger engine. Gearing comes later.
machinist@large
Active member
Doc Sprocket
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You should take some time, and enjoy a long stroll through this forum. Stuff like this is covered at great length, with lots of terrific examples to draw from. This is rudimentary stuff, and you need to familiarize yourself with it. Now, I have a question for you-
Can you weld, or have someone that can? Building a go kart frame is not a good candidate for your first welding job. In that case, you're best to buy a cheap used frame off Craigslist and build it up from there.
Can you weld, or have someone that can? Building a go kart frame is not a good candidate for your first welding job. In that case, you're best to buy a cheap used frame off Craigslist and build it up from there.
I've been working all year on a high mileage car in school so yes. I'm quite proficent with a cnc mill, cnc lathe, and plasma cutter too. I just have not done anything specific with the stock engine and gear ratio. The drive wheel on our car is a bike wheel with a polycarb sprocket screwed in, and it is only one wheel so a two wheel go cart is a weird concept for me.
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