79cc Lifan Engine Mods?

[Bullfrog]

Let us know how many miles each bike gets before their aluminum frames cracked, and where the cracks happened.

CrazyDan.....that is my concern. I was all ready to go with a 212 Tillotson engine but after getting my Phatmoto AT and weighing the 79cc Lifan that comes with it....the engine weighs 20.8 lbs out of the box.

I am concerned anything that is much heavier will over load the frame and cause problems in the long run.

Has anybody looked into using a Yamaha KT100 engine in their Phatmoto? The KT100 weighs 21 lbs and you'd have to add a clutch.

 

[DieselTech]

CrazyDan.....that is my concern. I was all ready to go with a 212 Tillotson engine but after getting my Phatmoto AT and weighing the 79cc Lifan that comes with it....the engine weighs 20.8 lbs out of the box.

I am concerned anything that is much heavier will over load the frame and cause problems in the long run.

Has anybody looked into using a Yamaha KT100 engine in their Phatmoto? The KT100 weighs 21 lbs and you'd have to add a clutch.

Yes I have, they make a complete ready to run model kt100 with a clutch set up. Better get your wallet out thou, there expensive!!! Plus the model I'm looking at was 22hp out of the box, theres no store bought/built bike going to handle that kinda power. You would have to build a custom steel frame to handle that kind of power.

 

[Bullfrog]

Yes I have, they make a complete ready to run model kt100 with a clutch set up. Better get your wallet out thou, there expensive!!! Plus the model I'm looking at was 22hp out of the box, theres no store bought/built bike going to handle that kinda power. You would have to build a custom steel frame to handle that kind of power.

Thanks DieselTech...Do you have a link for the KT100 package you found? If not, what clutch did it use? Getting enough gear reduction between the engine and the rear wheel is one of my concerns with the clutch being the 2nd concern. A 26" fat tire is a LOT larger in diameter than a kart tire .

I contacted Comet Kart Sales and they said a KT100 with a can exhaust puts out 6.1 ft lbs of torque at 6,600 rpm. IMO the Phatmoto drivetrain should handle that without any problems.

The KT100 with a can exhaust is what I am considering trying. An expansion chamber would be nice but I am afraid it will produce more power than the Phatmoto can handles...I would believe 18 hp from a KT100 with a pipe but anything more than that would be challenging and expensive.

 

[DieselTech]

Thanks DieselTech...Do you have a link for the KT100 package you found? If not, what clutch did it use? Getting enough gear reduction between the engine and the rear wheel is one of my concerns with the clutch being the 2nd concern. A 26" fat tire is a LOT larger in diameter than a kart tire .

I contacted Comet Kart Sales and they said a KT100 with a can exhaust puts out 6.1 ft lbs of torque at 6,600 rpm. IMO the Phatmoto drivetrain should handle that without any problems.

The KT100 with a can exhaust is what I am considering trying. An expansion chamber would be nice but I am afraid it will produce more power than the Phatmoto can handles...I would believe 18 hp from a KT100 with a pipe but anything more than that would be challenging and expensive.

Yeah I'll find a link for you, it's a complete package ready to run engine.

 

[Chainlube]

The Lifan is a 4t and the KT is a 2t. A quick Google search shows the KT list for $900 or a blue printed version at 2050.

I'm thinking the Lifan is a good choice.

 

[Bullfrog]

Common sense i.e. "reasonable cost" has not been part of the process....yet. At some point it will come into play.

I found a reasonable option with this one: https://iameusaeast.com/pages/iame-swift

It is a 60cc 2 stroke used for a junior class with SKUSA and has electric start, 10 hp, and 7 ft lbs of torque.

 

[Bullfrog]

OK, I did some calculations based on the fact that most 2 strokes that will fit in the Phatmoto turn about 10,000 rpm in the meat of the powerband. That means I would be going about 43 mph and that is a lot faster than I want to go...so 2 strokes are off the "potential" list of engines at least at this point in time.

Just my opinion but it seems like all of the 212cc engines are a little too heavy and too powerful for the Phatmoto to handle reliabley.

Has anyone installed a 4 stroke engine with a displacement between 79cc and 212cc? Just trying to find something with a little more power than the Lifan 79cc engine and lighter than the 212cc engines AND that somebody has verified will fit in the Phatmoto without too many modifications. Options I am still investigating are the Briggs LO206/Animal and the Honda GX series of engines.

Thanks for any info .

 

[Barnfresh]

Right now the hot Phatmoto All Terrain engine swap in the 1700 member Phatmoto Facebook Goup is the Honda GC190 or GS190 (full bearing) 187cc engine, as seen here on the Group cover photo. The engine is only a few pounds heavier and slightly taller than stock and installation in the AT can be performed with basic hand tools and a drill. Owners claim the 8.3 ft pounds of torque is a huge improvement over stock and speeds of 50 mph are easily achievable with zero pedal assist to get started. In fact one member who stuck with stock gearing had problems keeping the front end on the ground every time he took off, lol. Unfortunately these engines as well as the GC160 are too tall to fit in the Rover frame without cutting a big chunk out of the engine mounting plate.

 

[Bullfrog]

Right now the hot Phatmoto All Terrain engine swap in the 1700 member Phatmoto Facebook Goup is the Honda GC190 or GS190 (full bearing) 187cc engine, as seen here on the Group cover photo. The engine is only a few pounds heavier and slightly taller than stock and installation in the AT can be performed with basic hand tools and a drill. Owners claim the 8.3 ft pounds of torque is a huge improvement over stock and speeds of 50 mph are easily achievable with zero pedal assist to get started. In fact one member who stuck with stock gearing had problems keeping the front end on the ground every time he took off, lol. Unfortunately these engines as well as the GC160 are too tall to fit in the Rover frame without cutting a big chunk out of the engine mounting plate.

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Thanks Barnfresh...I backed into the same engine being best after days of research .

What clutch or torque converter is being used with the Honda engines?

Thank You

 

[Barnfresh]

Thanks Barnfresh...I backed into the same engine being best after days of research .

What clutch or torque converter is being used with the Honda engines?

Thank You

Most are using either the 3/4” bore Hilliard (needle bearing) inferno race clutch or MaxTorque Clone Race Clutch, 16-17 teeth with stock rear sprocket and governor bypassed or removed completely. Both have slightly higher engagement speed than their standard clutches. I don’t recall anyone running a CVT torque converter but I don’t see why a 30 series wouldn’t work unless the shafts CTC and limited engine adjustment back/forth puts it in-between available asymmetrical belt sizes.