china bike 122cc dohc 4 valve project

[tormentandglory]

Yeah, I figured they'd be pricey. They wouldn't give me a quote over the phone either. But they have some sweet cnc machinery so hopefully it'll all be good. Made plugs for the cam bores today. They look a bit like cam lobes Oil lines from the crankcase will be tapped into the back of them.

I don't know where to get the lil sucker dyno'ed even if I wanted to. Anyone got any suggestions where to take it? I'm in melbourne, eastern suburbs. Do they run em in the bike on rollers, or on a proper engine dyno test bench thingy?

 

[themountain]

OH Boy that thing is wicked!! ...with the cam ...mm... 260deg is quite ok I think...hotter and you will have problems with some valvefloat for sure...that thingy goes easy to 14 K ...eeek What valvesprings do you use??
Man...I would sell my grandma to have that engine

 

[tubes380]

just find a place that dynos road bikes, buy yourself a motard rear wheel setup and off you go, but its usually pricey, like $100 per run or something like that

 

[tormentandglory]

All of the valve related hardware i'm using in this engine is out of the zx2r kawasaki, and they redline at 18000rpm. So i don't think valve float is gonna be a problem. I expect the conrod will be the weak link, or the ****** chinese piston. Clive cams can grind me some 300deg, 6mm lift cams . I'll run what i've got first and if its to slow, new cams go in.

 

[Dreadful]

you're ripping

 

[MITTZ]

that is a freeking awsome project mate!

i was just wondering how you got into that line of work (engine machining, building race engines and that sort of thing) ? im looking for a career path and this sounds really interesting! i assume you did an apprentiship or something, tafe course maby? also whats the pay like?

sorry to get off topic but this would really help me out!
thanks in advance, Andrew

 

[tormentandglory]

I've been into mechanical **** ever since I could walk! Always tinkering with electronics and engines when I was a kid. Did engineering at box hill tech school. I got an apprenticeship in auto machining when I was 16. Worked at 2 different companies for the next 10 years. Did a performance engine development course at richmond tafe when I finished my apprenticeship. I think there's some money to be made in the auto industry somewhere, but I never found it. I quit and now I've been working as a toolmaker/fitter and turner for almost 5 years now. I only stay in this industry because it gives me access to an awesome workshop. We have 2, 3, and 4 axis cnc lathes, horizontal and vertical 3 axis machining centres, even the manual milling machines have 2 axis cnc control. I've got almost everything I could need for making my projects.
I can tell you one thing though, starting out using crap machines makes you a better tradesman. 10 Years ago I was pissing about trying to make cool stuff for my honda mini's on vintage machines. I made my own 88cc alloy barrels and ball bearing mounted cams. Thats a long time before you could buy any of this chinese crap you get today! Mastering old skool tooling is important before you move on to modern machines. Your imagination is the only limit once you can use cnc.
My next project is gonna be a v-twin. I need to make a crank and a set of cases. And god knows what else. But I gotta finish this engine first.

 

[themountain]

.....My next project is gonna be a v-twin. I need to make a crank and a set of cases. And god knows what else. But I gotta finish this engine first.

..and then you sell it to me yes,yes,YES !!!!!

 

[MITTZ]

thanks for the onfo! much appreciated!

 

[tormentandglory]

..and then you sell it to me yes,yes,YES !!!!!

Haha maybe... I probably will sell it as soon as I build something faster. But make sure you've got a fat wallet if you're intereted!

 

[tormentandglory]

hey, does anybody have a crf50/xr50 rear wheel they wanna sell? I need one. Only interested in genuine honda, preferably not to trashed. With the backing plate for the brakes to. Email me at [email protected] Thanks

 

[themountain]

Haha maybe... I probably will sell it as soon as I build something faster. But make sure you've got a fat wallet if you're intereted!

I figured that out ...bring it on mate!!

 

[wogtaz ryder]

I LIKE!!

 

[mad man]

respect...

 

[Hans]

Hey dude... reguarding getting you bike dynoed...i buitl and worked on a dyno that will give you all the specs your after ..when you get your beast up and running... speak to Greg.... ...and he will look after you in running your bike on the dyno.... .Buzz Bikes,Sly50s,Fast50s,Autocom,Ciniworx in bayswater wish i was reading this earlier i could have helped you out with cutting the seats on you head for you. i have alot to do with engine work and are also in the melb. area..I built a three valve 140cc engine it worked quiet well.....I hope your project gets you the horses your after.....

 

[tormentandglory]

Ah, cool. I'll take it down to buzz bikes when it's finished then. I know the place, thats where I bought the yx140 piston from. How did your 140cc 3 valve perform?

I'm a bit concerned that mine's not gonna be fast enough. Even if it works really well, its gonna be tough to catch bikes upwards of 140cc. Next time I'll start with one of those short stroke gpx150's I think.

 

[tormentandglory]

I bought another bike tonight. 1978 Z50j. It has a compliance plate and full electrics and speedo. It's all in really good original condition to. I'm gonna get it registered and put the twincam in it I've got a pair of 10" crf50 wheels to put on it so I can run race compound scooter tires. Legal mini riding anywhere, anytime... Awesome.

 

[Squeeby]

Legal other than the modified engine and non roadworthy tyres of course

 

[Hans]

Hey the "rx motovert 125cc "bikes they released not long ago is a brand new mini motard style bike that comes with full road reg.......$4000...i think...i would put a 150cc motor in it ..that be good fun and cheep transport..lol..

 

[Hans]

The three valve 140cc motor went very hard ......but not for very long it **** it self and broke the cam chain(chinese crap..lol) bent the valves and stuffed the piston so i built another...using a 110cc bottom end a 140cc piston a 125cc lifin alloy barrell (i picked out the one with the thickest cast sleeve) bored it to suit the 140cc piston....and moded the 3x valve head off the 110cc engine to fit on the bigger barrell..i did use a new cam chain this time ...all i want to now is get a 100cc 2 stoke go cart carby that you can tune and run the sucker..see what happens