25 hp to much ?

[BenDawg]

Hi all I am new to the aatv world but im loving it. I have a Max4 with a 18 hp Briggs in it. I was looking to put a new Kawasiki 25 hp liquid cooled motor in it. Is this to big ? I dont want to trash axels ect... I just think i need some more "uumph". Thanks all.

[whipper-ag]

Hi all I am new to the aatv world but im loving it. I have a Max4 with a 18 hp Briggs in it. I was looking to put a new Kawasiki 25 hp liquid cooled motor in it. Is this to big ? I dont want to trash axels ect... I just think i need some more "uumph". Thanks all.

You can never have too much HP. Trust me. Horsepower has nothing to do w/bending axles. running into things does. Go for it.

[jpswift1]

Recreatives is actually putting 29 HP Kawasakis in the Max IV's from the factory now. You wont have any trouble with a 25 HP engine. The T-20 is a super durable and quite the bullet proof transmission and it can handle gobs of torque and horsepower. The #50 chain is pretty strong and if you have concerns about axles (which shouldnt really be too much of a problem) you can always run solid splined axles. Good luck with everything.

[hydromike]

OK, honestly B-Dawg, I think you could quadruple that number. I regularly throw over 50hp at my 1972 Attex with the original driveline. (T-20, dinky 1" solid non-splined axles). I've seen springers that have run 70hp liquid cooled engines and running T-20s (with the same basic overall driveline). I'm not kind to any of my machines, and I'm yet to ever break a #50 chain. This includes dozens and dozens of attempts at carrying a front wheel stand over a distance greater than 20 feet. As long as you don't shock-load the components, these things really hold up well to abuse. What's very cool is that the components handle high RPM as well as the ponies. I can run 6000+ RPM in a machine for some sustained periods. Can you imagine how fast that T-20 is spinning when the torque converter is in overdrive? My guess is well over 10,000 RPM. I hope I never have to test the scattershield, but it's there just in case.

Like Whipper says: "you can never have too much horsepower"
Like Swifty says: "the T-20 is bullet proof".

~m

[BenDawg]

Great !! thanks guys. Now im actuall looking at a 39 hp Kawi motor. =) Or maybe even the old chevy big block in the basement =) Thanks all.

[Silverbullet75]

hmmmmm..

Now you got me curious...
Hi guys,
So, am I correct in assuming that as long as you can get the motor to physically fit in the machine, and the shaft is correct (or machined/fabricated to fit), then something like a, say, Harley V-twin, or crotch-rocket 1300cc motor "could" work? (I'm speaking for Argo Frontiers now... but please speak up on others )... or, why stop there... How about VW/Porsche Type 4 pancake motors (2000cc).

[Hey_Dan]

Harley V-twin

I think a Harley V-Twin would be perfect for a max II. Not too heavy, sounds good, plenty of power, and some of them are set up for a belt drive. The one downfall is that they are a "free air" engine. They have cooling fins but no shrouds or fan. It shouldn't be too hard to add them on though.
I think RI should come out with a "sport" model max II with a Harly V-twin. Even a low performance version (50- 60 hp ) would be a lot of fun! Add a suspension setup to the sport model and they might have to build a bigger factory to keep up with demand!

[Roger S]

Before I discovered briggs performance parts, I was looking for more power for my argo 8 with 18hp briggs. I have a '73 harley sportster and jokingly thought about putting it in the back of the Response. With a T20 and twin pipes sticking up like a drag boat

Also thought more seroiusly about the 1000cc 3 cyl suzuki motor. I think it is a more realistic idea. Still large, but not a lot of $. Well by the time it's fabbed in and finished.. maybe not so cheap.

Then discovered the briggs vanguard is raced by several groups. Of all the air cooled twins it is the lightest, is bulletproof and long lasting when built right, parts are available and "reasonable" compared to kohler and others. 30 hp is pretty easy to get, and Whipper's 23 hp block is rated at 50. That's without adding any weight. Added weight in a front heavy argo, even a max is not desirable.

I don't know what mine puts out, but it's enough to stretch my primary chains about double what it used to in the heavy argo. So I'm stopping there as far as power increase. When I get out of debt I want to do the same to a maxII. Scary power and a t20. A full expanded metal roll cage and a gell battery to make the learning curve safer

[mudbug3]

Roger S.

If whippers 50 hp motor was built from a 23 engine block ,would a milder 30 hp motor , built from the same engine block , be preferable over the higher torque out put of a 25 hp , Kolier motor , for turning 25 inch , Mud Bug tires in the mud , on a Max II ?

[Roger S]

A larger stock engine compared to a smaller high perf one would run on regular gas, have a quiet stock exhaust and kohler hydraulic lifters? A warranty. You could sell the original engine. Get a 23 briggs with 20-50 amp alt. Lots of reasons to buy new and bigger. I doubt the 25 kohler would have more torque, but it's power band would be lower where your stock clutches are already made to operate.

I just like it 'cause it's like being 18 again with a small block chevy with a few goodies in it.

[Moike]

HP - Never too much

I have a Pontiac Firefly 3 cyl in my Max II. It fill the cavity with the rad sticking out the rear as it does but works real fine. down side is horse power and fuel economy do not go together. I went from 6 or 8 hours of operation down to well under three. Upside, what a 3 hours it is!!!!!!!!!!!
Mike

[BenDawg]

Well thanks all. I am set on a 27 hp kawi engine. I will be installing it by new year I hope.