Engine upgrade possibilities!
 

Most of our bikes have the push rod, two-valve engine and it seems to serve us very well. Of course, “inquiring minds want to know” what other choices we could have. Would we not like overhead cams, 4 valves per cylinder, six gears (the elusive shift for another gear?) and counter balanced engine? MORE POWER – MORE TOURQE!

While just poking around the WEB during a weekend long rainstorm in my area I found some engine listings on E-bay that look like a direct bolt up to my Hawk frame. I thought that starting a thread on this could be interesting, even if no one gives any engine swap a try.

Example:

Model: LX166FMM -3
Type: single-cylinder, air-cooled, 4-stroke, vertical
Bore x Stroke：65.5X66.2mm
Ignition: CDI , electrical/kick start, DC
Gear Shift: Manual forward, 6 gears, international
Maximum net power/ rpm：12.5kw/8000r/min
Maximum torque/ rpm：17N.m/6000r/min
Gears: 1N23456

Gears : 6 foward gears for 2 wheel motorcycles
Default colour :Black

enging Kit:
1)Carbur:
2) CDI, Relay, Ignition Coil, Rectifier ( JT brand, Yammaha Supplier with top quality)

If you need this engine with wiring hardness (cable tree), Please refer to the following link:
https://www.ebay.com/itm/Loncin-250C...wAAOSwSk9chjnp

If you find options that look good as a possible upgrade – Please dive in and post.

We do not need this but like all of us that dream for more…more…more it could be interesting!

For the GREEDY – NOT the NEEDY

I would love to see someone try this out. Looks interesting.

torque and power are the same as a stock 229cc engine

This is just a sample and I did not look enough to find the best choices - Just thought it was tought provoking.

Specs that I found (but you know every thing you tind on the web is true (Ha! Ha!):

CG250:
Max HP 14.1/7000 RPM
Max torque 16.5/5500 RPM

Loncin 250:
Max power 16.75/8000 RPM
Max torque 17/6500 RPM

I am sure that there are even better choices to be found. This is why these forums are so much fun!

The engine you found is also known as the RE250. I've been eyeing one of these for a while to swap out simply for the extra gear. Power wise, you won't notice much. A bit more at the top of the rpm range, but a bit less grunt down low.

I was looking at the Loncin 250 if I ever had to replace the engine. That 6th gear would be nice for the street. I also like that it has a balance shaft and the engine is already prepped for an oil cooler. I have a post somewhere on here about it.

I think the bigger issue here is initial and final drive ratios even if it is a 6 speed gearbox. You might not be gaining anything other than moving your left foot more often. Now I do know with a performance engine more gears will allow you to stay in the "sweet spot" and get better acceleration times, but on these Briggs and Stratton engines the actual ratios would probably matter more.

For example I'm tired of going through Turbo 350 trannies in the old Chevy, even though I've got a mud kit in the last rebuild which seems to be holding up well. So I'm thinking about dropping in a 4 speed manual which will be bulletproof (and I prefer stick shifts). And 3rd gear in the manual is actually slightly lower than first in the Turbo 350 with zero power lost in fluid transfer. But there's a downside, if you try to shift a manual in the hole almost all forward momentum is lost and because of that the automatics almost always win. Better to keep power going to all 4 wheels all the time. But there are some guys that have figured out the absolute best ratio so they don't have to shift.

Idk, I absolutely loved my '88 YZ 80 and it would move, but even in 6th the top speed was about 60mph, maybe less, and I was always shifting.

For example I'm tired of going through Turbo 350 trannies in the old Chevy, even though I've got a mud kit in the last rebuild which seems to be holding up well. So I'm thinking about dropping in a 4 speed manual which will be bulletproof (and I prefer stick shifts). And 3rd gear in the manual is actually slightly lower than first in the Turbo 350 with zero power lost in fluid transfer. But there's a downside, if you try to shift a manual in the hole almost all forward momentum is lost and because of that the automatics almost always win. Better to keep power going to all 4 wheels all the time. But there are some guys that have figured out the absolute best ratio so they don't have to shift.

Idk, I absolutely loved my '88 YZ 80 and it would move, but even in 6th the top speed was about 60mph, maybe less, and I was always shifting.[/QUOTE]
Here is a chevy idea, posted by superchevy ….

1st through 5th are the same gear ratio as the Hawk. 6th is a 2nd overdrive. You will be able to gear it for off road and 6th will have you at the right gear ratio for highway. I'll have to find the post where I have this information already.
Link to thread. http://www.chinariders.net/showthread.php?t=18754

Exactly what Jerry said. 6th is a .8 ratio. This would allow for running a ratio like a 17/50, but with the highway capability of a 17/43 on our 5spd transmissions. Offering a best of both worlds scenario.

Had this link saved for a while for my shark if it'll push it up to 80 (I'm topping out at 68 through GPS with full gear currently) I'd buy it I just can't justify it otherwise

https://m.yoycart.com/Product/40634641602/

It'd sure be nice having that overdrive 6th gear. I'm about to swap out my rear tire after 4000 miles, and I have a 45T sitting in a box, but I just don't do enough highway mileage to really justify moving away from the 17/50 setup.

Still, I go back and forth on it continuously. I'll be glad when the tire is finally on there, regardless of what sprocket ends up with it, just so it's decided.

That's the same engine I posted over two years ago. It's not so much about top speed but the fact that you will have a more versatile gear ratio range allowing you to gear it low enough for off road and not lose top speed. At least now we know it's available through Ebay (thanks to LifeRider) and not having to worry about what the final shipping cost would be through Yocart.