Here is a question i just looked at extreme v twins website and for a stage III mod its over 3 grand i was thinking why not put a motorcyle engine on a SD motor the horse power is probably way higher and the availability of performance parts is almost limitless and at a much cheaper price. Anyone tried this yet. I do know of the long tail that had the harley engine on it and that was supposed to give out if I remember 75hp. much lighter engine to. Something to think about. Also depending on the engine its possible to put a turbo charger on it.

Why not really go out and put a 350 chevy?

I am trying to be realistic, but if you want the Thai people have been putting car engines on longtail motors way before we even thougth of the concept of mudmotors. I am tring to address the biggest issues to plague these motors and that is weight and horse power. The biggest bang for the buck could only come from a motorcycle engine. and if you want to go a step further profile and center of gravity. I know personally guys that could not go into an area due to the only access being under a bridge with a high water level it made it unaccessible. Now if you could use a Boxer type motorcycle engine and have a very low profile engine plus the combination of smoothness, power and light weight how much more enjoyable would running a mud motor be.

on sport bike engines like the CBR or ninja they high rpm hp. not low end torque. That would kill your hole shoot but if you could rev. it up to 12000 grand the mud would fly.

Ever heard of the Cushman ????

Evolution mines friend ..... Evolution !!!! Build it and thay will come !!!

sure do miss my old eagle. Why not the idea of a motorcycle engine. good thought.

I think you are missing the major concept behind these things; simplicity. If you were to put a motorcycle engine on one it would have to be a harley big twin motor(evo,twin cam) because of the fact that all others have a gear box built into the crank case. The big twin harley motors have a seperate transmission. If you try to run one with a transmission I dont think it would work but who knows. But who wants to have to switch gears and so on. Then you also have to worry about cooling which would probably be fine while your cruising around but once you get stuck and start reving high with no air flow it will get hot really quick. If you really wanna haul a** getting an outboard is the best suggestion. If you just want a little more speed mod it. No need to reinvent the wheel.

Not trying to reinvent the wheel just stimulating some thought and brainstorming. Can you imagine a turbo charged mudmotor.

I tried to mount my favorite engine, the 2-stroke ROTAX 277 26hp, to a long drive shaft to make an early long-tail. My efforts failed cause I used splined hubs as gear reducers and the darn Kevlar belts of the time kept throwing teeth.


Long story short, I came real close to making an early surface drive.
NOT using a motorcycle engine, but an ultralight aircraft engine.
That Rotax 277 is a very light, high horse-power, unit!
IMHO ultralight aircraft 2-strokes are the way to go if you want to "experiment" in 2-stroke mudmotors.

Motorcycle engines-lots of power but they do get HOT I own a Harley and in a matter of a minute that thing is hot and youve got to be cruising to keep em cooled when you sit in one spot for long just idleing you can feel the heat i could only imagine being stuck and hammerin down,unless you put a radiator engine on it and then your adding weight to something that isnt that light in the first place, but im not putting down the idea it can be done,its been done before, but just like everything there are obstacles are set backs

everything thats been mentioned here has been tried. Everyone always goes back to what easy and most common.

It is a balance thing. Weight, horse power and last but most important cost. All of the High horsepowere 2 cycle motors are verry light so they need to be going to keep cool.when they stop they need to be heavy to absorb the heat to not self destruct. The good ones are very spendy - far is excess of the cost of the usual types used on a mud motor.

What is currently used is the most bang for the buck in terms of pure fun or great utility.

To address the Cushman thing. My Cushman Had an 8 HP heavy cast iron engine that was HEAVY. I don't know that it turned more than 3,000 RPM. It was a lot of fun but it didn't hold a candle to the current 7 HP motor that I use and is so popular now.

Mark F. Cheney

Yep- alot of stuff has been tried before. Has to be practical, dependable, and manufacturable to be viable.

i'm not familiar w/ 'em, but mud boats (i think w/ the drive shaft going through the floor) w/ subaru engines are pretty common in south louisiana. the ones i've seen have very low profile hulls that look like a disaster in anything above 1 ft seas.

There is guy on MB forums running a Rotax right now and says he will demo it at Sparkleberry fun run.

Turbo would be another option.

why not a 4 wheeler motor light and powerfull i have yamaha yfz 450 4 stroke that with the right mods can make over 50 hp. its liquid cooled but very light compact and lots of torque

They do ok my cousin has one with duel carbs but can't open it up because it porpoises too much. There nice and fast as hell till you hit something in the water. Thats the reason I went with the GT I like to stay in the boat when I hit something not fly out.lol

I have been prepared to talk about this for a lil while now. A lot of good points were mentioned but some of u guys aren't understanding that u can't just put any motorcycle motor because everything but the harley v twin has the trans made onto the motor as stated above. Now as for as the harley its a great idea. As long as u have a small electric fan that thing isn't gonna ever get hot. Ever, stuck or not.

An oil cooler with fan and a Parade fan may help the situation. The BMW would be another option.

Finally got some time to reply, over here in Afghanistan rightnow been busy. Anyway, I am glad to see some of you guys are thinking and opening up your minds about types of engines. That is why i started this thread. Briggs and strattons are good motors don't get me wrong. but with thought and ingenuity someone out there is going to build a faster lighter stonger engine then we won't be held hostage to 1700.00 mod kits anymore. Keep thinking about it and i am pretty sure someone with have a turbo charged motor soon.

Thanks
Matt

Those inboard mud boats are nice and go through some bad ass chit but they are gas guzzeling HIGH maintenance my buddy from Morgan City has one that roles about 40+ with 4 hog mollys in her.It's powered by an American made big block in an aluminum hull and the only thing that stops it is mud hidden under a load of lillies .The rotax has been tried its got the rpms but not the torque needed.Atleast thats what I've been told.If it would have worked it would have already been bolted to a frame by now being marketed as flying on the water or something like that.Do not worry there will be another option out there soon just wait and see.