Billet rod for 49cc/53cc engines

[Chainlube]

I've done a pile of 4 stroke flywheels and never used a puller once. If you cut the key you don't need another flywheel.

 

[Street Ryderz]

I just thought if you were making a CNC rod you could add to the length a little maybe getting 9.0:1 or 10.0:1 along with the cam and honda flywheel. It would be like a stage 4 50 lol.

Here is how to do the fly and coil:

[How-To] Ungovern HuaSheng 142f

I'm working on ungoverning my HS 142f and since I haven't seen any "how-to" post which I'll find useful, here is mine, for now "work in progress". I'll keep updating this first post as I can invest hours on this. Special tools needed: - Balancer Puller (to pull the flywheel, learned kind of the...

motoredbikes.com

You can't change the rod length that much and no where near enough to change the compression ratio that much, with a 4 stroke or 2 stroke a stroked build requires a different crank and rod and with the 4 stroke if you change the cylinder height you then need to use slightly longer pushrods, then check the valve clearance and make the necessary relives if it is tighter for more compression and a cam also ideally you would put a larger exh valve and slightly bigger int valve to make use of those changes and then flywheel and ignition all at the cost of more then just buying a better engine IMO for such little gains not worth it. Also when reading post's on the other or any forum don't forget that there are many whom don't know wtf they are talking about, research your idea's ask question's to make informed decision's because it sucks when you're miles from home and you're pushing or pedaling the bike due to failure.

 

[Will'smotobikes19]

Ya push rods as well forgot that for a second but by watching some of the 212 builds they did use longer push rods and rod. The bigger valve idea could work but the difference wouldn't be much maybe 1- 1.5mm difference they are straight up and down in the cyl I think. Wouldn't be worth it to me. Quite a small cylinder bore but already has pretty good compression ratio. Porting and polishing could help. Could try on the motor I have now.

 

[mark20]

id say a custom longer rod could work, as it would effectively increase the compression ratio.

might be possible to get longer valves as well, and then add in a bigger cam (to get more airflow in for a long amount of time, in there anyway) if there's actually any room left.

could be possible to mill out the cylinder for a bigger piston (maybe about a 3mm big bore?)

id say if your really serious about making engines go fast, this platform is pretty limited, id say a 97cc mini bike motor would be a better choice

https://www.amazon.com/Lifan-LF152F-3Q-4-Stroke-Industrial-Universal/dp/B008H2FZUI/ref=asc_df_B008H2FZUI/?tag=hyprod-20&linkCode=df0&hvadid=198076851563&hvpos=&hvnetw=g&hvrand=5445802290449770649&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9019592&hvtargid=pla-319503380371&psc=1

 

[Will'smotobikes19]

I think a 49cc capable of 42mph would be nice. Yeah the phatmoto motors brother seen those. They seem to top around 30mph same as the 49cc .7 hp more rated 2.8 vs 2.1. Similar to the subaru 35 vs honda 35 1.6 vs 1.3hp although both are too low power for me already tried subaru. Too slow on inclines. It's strange how a 97cc can only be .7 hp more except the rpm differences and such. It would be a cool experiment. Making a blueprint for both billet rods and testing, heck maybe a 49cc rod, 79cc rod and the 97cc rod. Restriction will be flywheel and springs.

 

[CrazyDan]

id say a custom longer rod could work, as it would effectively increase the compression ratio.

might be possible to get longer valves as well, and then add in a bigger cam (to get more airflow in for a long amount of time, in there anyway) if there's actually any room left.

could be possible to mill out the cylinder for a bigger piston (maybe about a 3mm big bore?)

id say if your really serious about making engines go fast, this platform is pretty limited, id say a 97cc mini bike motor would be a better choice

https://www.amazon.com/Lifan-LF152F-3Q-4-Stroke-Industrial-Universal/dp/B008H2FZUI/ref=asc_df_B008H2FZUI/?tag=hyprod-20&linkCode=df0&hvadid=198076851563&hvpos=&hvnetw=g&hvrand=5445802290449770649&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9019592&hvtargid=pla-319503380371&psc=1

The 53 cc hs144f has a 1.7mm overbore on the 49cc hs142f.

 

[Will'smotobikes19]

The 53 cc hs144f has a 1.7mm overbore on the 49cc hs142f.

Have seen they recently upped the price on those, before they said they were stuck in china and wouldn't ship. If one had the right tooling you could build one just using the bigger piston perhaps, it's only $220 still. With Honda OEM length rod and a 53cc bore, or billet rod, porting, different carb, some other upgrades that would be a nice package. I think the cast rod will break before flywheel as I've only seen pics of broken rods. I did a snow burnout and donuts. Still too cold to ride hovering around 30 degrees. They are rebuildable and usually it won't damage the cylinder, sometimes crankcase but with some fine sandpaper and a new rod one of these can run again. That's another thing I like. I had an old 6hp iron block Tecumseh and I replaced the rod on it the aluminum cleaned right off the crank and it was ready to run, sadly someone bought it before I saw it running lol.

 

[Will'smotobikes19]

The 53 cc hs144f has a 1.7mm overbore on the 49cc hs142f.

Dan did you port yours? I see the exhaust port is indeed smaller diameter than the kit flange as the box muffler seals on the ridge around exhaust port.

 

[CrazyDan]

I'm still waiting for something to break. With regular oil changes and adjusting my valves, no issues. It seems I have Fixed all the weak links and am waiting for something expensive to break now. This is my daily driver and I have raced it. #17 in the brown leather jacket and white helmet. Dropped my chain after a few turns... fixed that problem now. You can see me near Neil with my bike at 3:03 telling him my bike was out then cut across the track when it was clear.
I enter from the left right where the vid starts cutting across the dirt because I jumped in for lulz at the last moment. Everyone else is 66 and 69cc 2 strokes tuned as fork.

Here is Tyler6357 #47 out for a sunday drive in the middle of a race .

That was my first race, don't knock the knobbies . Have Maxxis Hookworms now. Also much faster now, was running stock air box then.
I haven't done any porting yet, and still running the stock carb. Have the sbp air filter for it and jetted it proper. Wondering if the gx100 carb would bolt on, it's a 15mm. Looks like the same bolt pattern, but not sure on measurements.

 

[mark20]

I'm still waiting for something to break. With regular oil changes and adjusting my valves, no issues. It seems I have Fixed all the weak links and am waiting for something expensive to break now. This is my daily driver and I have raced it. #17 in the brown leather jacket and white helmet. Dropped my chain after a few turns... fixed that problem now. You can see me near Neil with my bike at 3:03 telling him my bike was out then cut across the track when it was clear.
I enter from the left right where the vid starts cutting across the dirt because I jumped in for lulz at the last moment. Everyone else is 66 and 69cc 2 strokes tuned as fork.

That was my first race, don't knock the knobbies . Have Maxxis Hookworms now. Also much faster now, was running stock air box then.
I haven't done any porting yet, and still running the stock carb. Have the sbp air filter for it and jetted it proper. Wondering if the gx100 carb would bolt on, it's a 15mm. Looks like the same bolt pattern, but not sure on measurements.

I know that a predator 212 carb will bolt on, but your going to need to figure out a throttle bracket for it, as there is none, the SBP adapter won't work unless you drill it out, stock airbox requires a bit less work to make the choke fit.