Phatmoto Pro 125cc 4-speed?

[Vikingimike01]

The weight sucks yeah but the deal breaker is it physically not fitting inside that frame. @Vikingimike01 lay out your 2 stroke maintenance schedule vs your 4 stroke maintenance schedule please humor me cause once either jetted correctly or the carb mixing needles are set 2 strokes are nearly zero maintenance.

Ever since I got my 2 stroke I just had trouble from either s**tty parts that just failed, or the too much maintenace, stuff breaking, screws loosening.. I loved my 2 stroke but hated to do anything with it, it leaked gas and whenever i rode it i smelt like burnt oil. I'd be much happier with the 125cc, and it would probably not have issues out of the factory. And as motorhedfred said, it has BUILT IN GEARS wich you can only get with a jackshaft for a 2 stroke and in total the jackshaft and the engine would come out to the price of a 125cc wich will probably also last longer if ridden the same way.

 

[FNTPuck]

You're making a big deal about the extra weight of the 125 but it also has nearly twice the displacement of the 2-stroke 66cc, probably more than twice the torque AND it has gears. You could argue that it will affect handling...definitely if you try to cram it in there with the cylinder pointing toward the head tube. However, if you install with the cylinder pointed foward the way it's designed to run, the impact on handling would be minimal. The reason is the drivetrain weight will be at or below the axle centerline.

4strokes are allowed double the displacement of a 2stroke for "similar" performance so thats not really a pro - the extra TQ is at the expense of HP compared to a similar sized 2stroke. Having gears is nice if you live in a hilly area but its still kind of a turd with barely 8hp and 50lbs of weight. You can easily get a chinagirl to 5-6hp for cheap and it probably weighs somewhere between 10-15lbs. Thats a HUGE difference in braking, handling, and strength of parts needed when you add ~40lbs to a motorized bike. Even with the motor horizontal all that extra weight still has a dramatic effect on handling.

This is coming from someone who has shoved a 70lb big bore briggs+40 series TQ converter combo onto what started as a bicycle frame so I am not against big motors(I think its badass!), but there is no real appeal to using the heavy lifan 125cc over a predator212 that is cheaper, lighter, more powerful, much larger aftermarket, and already more acceleration than you can use on a normal bicycle unless you want an off road setup and need the climbing low gears and don't want to run a big converter. The gears are mainly a convenience on the street, not a necessity compared to a properly geared single speed. The predator is just about perfect for a "big" motorized bicycle build and the money saved can go to some quality hubs and wheels.

If I wanted gears on a motorized bike I would do a KTM65 or even a KX85 or RM85 pull from a wrecked dirtbike. Then you can get DOUBLE the power of the Lifan, a super strong 6sp transmission, water cooling, and probably still be a lighter package. It would be a monster!

 

[FNTPuck]

Ever since I got my 2 stroke I just had trouble from either sh**ty parts that just failed, or the too much maintenace, stuff breaking, screws loosening.. I loved my 2 stroke but hated to do anything with it, it leaked gas and whenever i rode it i smelt like burnt oil. I'd be much happier with the 125cc, and it would probably not have issues out of the factory. And as motorhedfred said, it has BUILT IN GEARS wich you can only get with a jackshaft for a 2 stroke and in total the jackshaft and the engine would come out to the price of a 125cc wich will probably also last longer if ridden the same way.

While it wouldn't be my first choice for a reliable commuter, with todays aftermarket you can easily build a chinagirl for reliability over thousands and thousands of miles.

Sleeved cylinder, Japanese bearings for crank and clutch and stihl 10mm needle bearing for the rod, malossi circlips, and caber rings for the motor. CNC or moped head to keep it cool, and don't go too crazy on the compression. Then get the OZ mag and supercharge CDI which are both less prone to failing than the stockers. If you're worried about clutch issues, on a mid range build you can get a billet pressure plate and make your own pads. With an increase preload you will have a clutch that lasts ages and won't slip anymore. Spend a few bucks on an NGK plug and wire since the stocker gets brittle and lets in water that rusts it out and you are good to go.

All cheap parts that will make your chinagirl MANY TIMES more reliable than the cheapo $100 ebay kits floating around. I have a customers setup with just a ~$30 G5 sleeved cylinder and $3 malossi circlips that has over 4,000 miles on it in 7 months and still runs like the day I built it for them. Drives it every day to work and back, using 32:1 walmart oil - nothing fancy. Stock rings, bearings, head, and clutch still(although third set of pads)! Went through the stock magneto at around 1k miles, which was its only issue ever.

 

[Vikingimike01]

Sleeved cylinder, Japanese bearings for crank and clutch and stihl 10mm needle bearing for the rod, malossi circlips, and caber rings for the motor. CNC or moped head to keep it cool, and don't go too crazy on the compression. Then get the OZ mag and supercharge CDI which are both less prone to failing than the stockers. If you're worried about clutch issues, on a mid range build you can get a billet pressure plate and make your own pads. With an increase preload you will have a clutch that lasts ages and won't slip anymore. Spend a few bucks on an NGK plug and wire since the stocker gets brittle and lets in water that rusts it out and you are good to go.

How much money does that come out to? How much work hours do do that? Waiting time for shipping? If something doesn't arrive extra wait? Sorry, but no thanks. I do like 2 strokes, but they just gotta be better than this.

 

[FNTPuck]

How much money does that come out to? How much work hours do do that? Waiting time for shipping? If something doesn't arrive extra wait? Sorry, but no thanks. I do like 2 strokes, but they just gotta be better than this.

Lol it was like $80, installed during initial assembly so barely takes any time, and the parts came in 2-3 days from Treatland or MZMiami. It's really no big deal, you're still under $200 for a 2stroke that will last years and years.

Not sure where you're going with 2strokes needing to be better - we are using bottom of the barrel mass produced Chinese knockoffs built as a copy of a simple low performance design. Nothing to do with it being a 2stroke, just being cheap. It would be silly to expect any sort of longevity from them out of the box. Its just a starting point for someone who doesn't mind tinkering, not someone expecting to spend $90 for a full kit on ebay and slap it on for 5,000 trouble free miles.

There is a reason a KTM50 clone is over $400 without a pipe, mounts, tank, etc and a complete chinagirl kit is around $100.

 

[Vikingimike01]

Dude, that is in america.. In Europe, at least where I live, it's 200$ for a 2 stroke, and all those parts you listed with shipping would be over 50$ maybe even 100$. I know my reeds were 100$ with shipping....

And, exactly, what you said. It's just a starting point for someone who doesn't mind tinkering. I'd like an engine that I don't have to tinker with.

So I'm better off just getting a 4 stroke still.

 

[Frogslayer]

Sure are if you want a slower, heavier, more expensive motorized bicycle with higher maintenance.

 

[Vikingimike01]

Don't think it will be higher maintenance, but your opinion I guess... It's better tho.

 

[LewieBike]

That engine belongs in a pitbike or an old classic Honda..

 

[Vikingimike01]

Yes, it does, and they look amazing. I'm going to make a frame inspired by a "retro" motorcycle for one, if I do get one. Depends on how my electric bike turns out. (When I get the frame)