# Horse power



## mowerman42 (9 mo ago)

I have a 6 horse laying around I want to put into my mower for racing would 6 horse be enough to get it decently fast?


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## pogobill (Jan 31, 2012)

mowerman42 said:


> I have a 6 horse laying around I want to put into my mower for racing would 6 horse be enough to get it decently fast?


Welcome back. No luck with your last post in projects, I see. 
My best guess would be that the 6 HP engine would be way faster than the mower without an engine.... unless you are working on a different tractor now.
Some details would be in order, I think. What type of mower? Brand of mower you have and a few numbers on model and serial number. This would give the members a bit of information to lead you in the right direction, as was mentioned before. If you are having difficulty identifying your tractor, throw a few pictures up for us and we'll try and help you figure it out.


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## pogobill (Jan 31, 2012)

Here's a thread to look through!








Kubota 2 cylinder diesel powered HondaRT5000


I'm in the middle of installing a kubota 2 cylinder diesel into a HondaRT5000. Has anyone attempted to do this or something similiar?




www.tractorforum.com


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## mowerman42 (9 mo ago)

pogobill said:


> Welcome back. No luck with your last post in projects, I see.
> My best guess would be that the 6 HP engine would be way faster than the mower without an engine.... unless you are working on a different tractor now.
> Some details would be in order, I think. What type of mower? Brand of mower you have and a few numbers on model and serial number. This would give the members a bit of information to lead you in the right direction, as was mentioned before. If you are having difficulty identifying your tractor, throw a few pictures up for us and we'll try and help you figure it out.


It’s a ariens yt 10 it’s alright but the tranny has no gears and no other parts does have to motor but it’s too much money to flip the vertical to side shaft for a live axle so I thought maybe the 6 horse could hopefully cut it


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## Ford5610II (Jun 11, 2020)

Your mower originally came with a 10hp engine. The standard horsepower for an '80's or '90s unit was 10 to 15hp, and on up. My _opinion_ is that the 6hp would work for mowing, but may be too small for racing.


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## mowerman42 (9 mo ago)

Ford5610II said:


> Your mower originally came with a 10hp engine. The standard horsepower for an '80's or '90s unit was 10 to 15hp, and on up. My _opinion_ is that the 6hp would work for mowing, but may be too small for racing.


I just want to get it going until I can put a big one in so I can get to work now


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## Vigo (Oct 8, 2021)

In terms of how much power to go how fast, if you compare to something like a 150cc 4 stroke moped, some of the crappier ones weigh ~250 and have about 6 hp and go about 40mph.

A stock 'predator 212' has about 6.5hp and a mini bike with a stock 212 will go 30+ mph.

A mower of any kind probably weighs more, definitely has more rolling resistance, driveline losses, and aero drag (go full tuck lol) but it shouldn't be a problem to get one up to 20mph with 6 hp.. eventually.. but if you're trying to do it without shifting gears, any gear tall enough to go 20 is gonna have you smelling like burning V belt by the time you can let the clutch fully out. Might need to get a good running start like a bobsled before you hop on, slam it in gear and pop the clutch out at 900 whole rpm and LET ER EAT 🤣

I put a stock Predator 212cc on my Case 444 garden tractor. It will do the full stock top speed of about 9mph in high range, and it will push and pull decently hard in low range. It would spin the tires before stalling the engine originally, but i filled the 8-16 rear tires with about 100lbs of water each, and now it stalls before spinning tires.  But these are ~31" tires about the same size as what you'd find on a base model half ton pickup, so a bit harder to light up than most 'riding mower' tires.

On the plus side though, HP is partially a function of rpm, and small engines are usually rated for whatever hp they can make at 3600rpm as that's a typical governor setting for small engine equipment. MANY of those engines will make more HP just by spinning faster. For example, a stock predator 212 makes ~6.5hp at 3600, but over 8 at ~4300, and i think can hit 9+ just by slapping a cone filter and straight pipe on it. That's a ~50% power increase for basically free. Your 6hp engine might be similar.


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## Busted Tractor (May 22, 2018)

Often see this type of question posted. An engine used for chores such as a lawn mower/tractor has a top speed around 3600 rpm some can safely turn up to 4000, the limit usually being the connecting rod.. That is what limits the speed of the vehicle. The manufacturer controls the speed by reducing the input speed of the transmission. Most racers change the pulleys to alter that input speed so the axle speed is increased.
Also remember most of the horsepower of the engine is used to power the cutting deck, it takes a lot less power for propulsion of the tractor. Most racers use, at least the ones I have come in contact with, use a separate transmission and axle. 
Lawn mower racing is set up by classes, so you can find a class you should be competitive in.
Here are some websites for you to investigate,

** The United States Lawn Mower Racing Association ** (uslmra.com) 

Home (lawnmower-racing.com)

Enjoy and have fun


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## mowerman42 (9 mo ago)

yeah i just want to put this in to get it set up till i have another motor to swap i was going to put a cvt in it


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## Vigo (Oct 8, 2021)

As far as i know most CVTs have a slight overdrive when fully 'shifted'. So if your engine spins 3600 your driven pulley might be spinning 4000 when the cvt is fully shifted. So between a slight increase in engine speed and a CVT, you will get some top end just from that, even if you had the same pulley ratio from the CVT to the trans as you had before. But to get a mower up to anything dangerous/fun (10+ mph😂) you're going to need to change pulley ratios between the CVT and the back axle anyway. I'm assuming this is a vertical shaft engine & mower? If it's horizontal shaft it's potentially easier because you could just put a 'live axle' under the back and pick what pulley you want on it, at which point regearing the whole thing would be essentially the same level of difficult as regearing a go kart and wouldn't require you to deal with any weirdness of the input shaft of the stock mower transaxle when trying to change pulley sizes/ratios.


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