I would like to put a 340 2cycle into my TRI-ROD anyone ever use a 340 Yamaha snowmobile engine in anything? I know TRI-SPORTS used snowmobile engines like this. So I thought about putting this into my TRI-ROD I would change the primary and secondary too. I think it would make it more fun to ride with a 340 I have a 10hp Tecumseh on it now. Has anyone ever used any snowmobile engine on anything like a mini bike or go cart?
Engine replacement?
- Thread starter Cuda54
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I haven't seen or heard of any trike that came with a 340 Yamaha. But, millions of the engines are out there. Decent, reliable, mild state of tune. The 300/340 are just different bore. The later 410 had plated instead of sleeved jugs, crowded the limits of the stud spacing. I have a 300 that needs a rod replaced, but otherwise complete. Local Craigslist, scrap yard, etc.
The 340 Yamaha is just the smallest twin cylinder I know of right now. All of the Counja and the JLOs Artic Cats and Rotax are 440s or bigger. Some of the real old ones were 290 to 340 singles. I know it is not supposed to be on there but it is what I want to do. I want it to run a little faster and have more power to go anywhere. I even have the ski for it to play in the snow.
Physically, they are quite a bit smaller than a lot of twins.
They're cheap, light, compact, has the twin sound and smoothness. A bit plastic-y for vintage looks.
My Hirth 338s are taller, narrower, give up a little top end for a mean midrange.
I'm still hunting for a Polaris 372 single. Some were 396cc in the racers. BIG piston
Either way, tripling the horsepower on the rigid-axle short wheelbase machine should make for cool wheelies.
I'd set the clutch up a little softer than stock.
They're cheap, light, compact, has the twin sound and smoothness. A bit plastic-y for vintage looks.
My Hirth 338s are taller, narrower, give up a little top end for a mean midrange.
I'm still hunting for a Polaris 372 single. Some were 396cc in the racers. BIG piston
Either way, tripling the horsepower on the rigid-axle short wheelbase machine should make for cool wheelies.
I'd set the clutch up a little softer than stock.
If its the older style Yamaha, they lean a fair bit forward for the way they were mounted on a snowmobile.
However, you can get it standing straight up just by changing the way the engine mount works.
I have used a 340, 2 cyl Kawasaki engine out of a John Deere snowmobile, put into a trike.
With the snowmobile clutch drive and the gear ratio I used, it would do 50mph down the pavement.
Had to load the front wheel with fluid, in order to keep the front wheel on the ground and removed speed vibration.
However, you can get it standing straight up just by changing the way the engine mount works.
I have used a 340, 2 cyl Kawasaki engine out of a John Deere snowmobile, put into a trike.
With the snowmobile clutch drive and the gear ratio I used, it would do 50mph down the pavement.
Had to load the front wheel with fluid, in order to keep the front wheel on the ground and removed speed vibration.
I've run several JLo singles on Tri Sport TS series ,some came original and they are the ones I like the best. Your Tri Rod should be a easy trike to do this to & is a heavier trike & has a strong frame. But does yours have the independent rear suspension ? BGW used rubber donuts for universal joints on the axle and I don't know how they'd hold up to the power of a twin. If you found a vintage Kohler 340 or 290(twin)it should fit in there pretty easy and depending on sprockets would get you up to 65mph...maybe more !
Once you ride a 2 stroke trike you'll never go back to a 4 stroke Briggs or Tech.
My stock 230-290 single JLo Alsport TS trikes hit 48-51mph...but do it quickly !
Once you ride a 2 stroke trike you'll never go back to a 4 stroke Briggs or Tech.
My stock 230-290 single JLo Alsport TS trikes hit 48-51mph...but do it quickly !
Thanks! I think I can get the whole sled for $50 it is a 1980 340 exciter. I have a independent rear axle it has rubber to flex the axle now. But I plan on putting in new universal joints when I put in the new engine. I rode a TRISPORT my cousin as a kid so when I got the TRI-ROD. I had plans to make it run that way.
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Well the Exciter will not have the " Lean forward engine " so that's a plus.
CDI ignition, Float carb, You will need to do something about the throttle cable and choke set up.
Should be a good engine with about 35hp ( off the top of my head ) an not checking.
However, you may need a different prime clutch, I think Yamaha's is a splined shaft clutch.
What size is your axle / jack shaft?
CDI ignition, Float carb, You will need to do something about the throttle cable and choke set up.
Should be a good engine with about 35hp ( off the top of my head ) an not checking.
However, you may need a different prime clutch, I think Yamaha's is a splined shaft clutch.
What size is your axle / jack shaft?
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Well what I had planed was to use driver and driven. I has a single carb and had planed on putting disc brakes one on each wheel. The jack shaft will have to fit the driven then adjust the gearing after I see how it runs. I had planed on the electric start and use a wheel chair sealed battery. I use one on my 1978 Harley with a 93ci Stroker kit and high torque starter it is smaller than the stock one too. It is a deep cycle too! I used to run a 377 Rotax with twin carbs and loved that little motor. I would clean and adjust it as needed. It would out run a lot of 440s and yes it would pull the skis. But right now I just can not find one or that is what I would use I like twin carbs too. I think the axles are 1" and they will have new universal joints too. I also plan on new bearing if any of the old one are no up to pare.