[cdoublejj]

SP TAKEGAWA : [01-00-0048]

they definitely beefed it up, i remember when folks were hopping up the stock engine before the big mill chinese power plants hit the scene. kind of makes me wonder if anyone one has run them and how far they have pushed the stock style engine?

 

[TankTheory]

Maybe @storminnorman07 or @dirtbkr188 can chime in regarding how far you can push a set of cases. I personally haven't seen anyone go past 125cc.

 

[storminnorman07]

I have pushed stock 50/70 cases to 157ish cc 59mm bore x 57.5mm stroke. You would be able to go bigger with the takie cases cause they redesigned the oil pump to be driven off the crank vs stock being driven by shaft and ean by cam chain. That shaft limits how big you can go on stroke.

 

[50race]

Probably still end up machining out the crank case webbing circle trying to go much bigger stroke unless they increased it to trx90 size or cough NICE110 crank diameter clearance.

 

[TankTheory]

I have pushed stock 50/70 cases to 157ish cc 59mm bore x 57.5mm stroke. You would be able to go bigger with the takie cases cause they redesigned the oil pump to be driven off the crank vs stock being driven by shaft and ean by cam chain. That shaft limits how big you can go on stroke.

Just came across these cases - GCRAFT and boy are they beefy.

 

[nielspbr]

Looks to me that those g-craft cases still have to deal with an oil pump drive shaft interfering with big stroke cranks.

 

[fatcaaat]

The reinforced cases by takegawa are Honda Nice 110 copies and directly interchangable with minor tweaks. As for stock cases, I took one out to 58 bore and 56 stroke...and put approximately 1500 miles on it. In that 1500 miles, it ate several head and base gaskets. One of my Honda Nice engines is 58 bore and 66 stroke and doesn't suffer from issues with head gaskets or base gaskets probably because the germans that built it did a better job than I did on my own.

 

[50race]

With the Takegawa cases you could still be stuck with 54mm stroke and 54mm bore from off the self parts I'm betting(ignoring scut 57mm). If you bore the Takegawa cases to fit cylinder skirt for 58mm piston you open up to 58mm bore x 62mm stroke parts you can buy. Next step have the cases further machined to fit the 66mm stroke crank. Then you can get 58mm bore x 66mm stroke. With 59-60mm bores having been done if you really want to push it. After that you have to look at SEasia parts they changed the stud spacing on the cases a lot and have cylinder and heads setup for 62mm 62 bore x 66 stroke (200cc) is the biggest I think has already been done with modding stock type parts. I have seen claims of larger stroke but unsure if possible. Maybe with special transmission gear ratio setup to clear the crank.

Where does it stop counting though. You can buy cases modded to fit a Grom cylinder and head on for 65mm ish bore. 220cc

 

[nielspbr]

You can buy a stock zongshen 212, cases look ugly but fits in standard honda 50 mounts...
Or upgrade its more refined brother daytona anima from 190 to 212cc, same internals but 4valve and better looking engine covers.
(For those who don't know, the daytona 190 is built in de ZS factory...)

 

[fatcaaat]

I did a custom crankshaft on a set of midblock chinese cases at 68mm with a 58mm bore and a lot of top end work. I had to trim the bottom part of the connecting rod so it would clear the transmission. The motor was so torquey that I could not keep the flywheel from shearing the keys. Eventually I had to put a inner rotor on it and sold it to a guy that wanted to cheat in his pitbike class when no one had anything bigger than 57mm strokes.