Custom 70cc engine build

Is it worth it or stupid?

  • YES

    Votes: 20 62.5%

  • Hell no

    Votes: 2 6.3%

  • Kinda

    Votes: 4 12.5%

  • YES

    Votes: 3 9.4%

  • Nah I'll pass

    Votes: 3 9.4%
  • Total voters
    32
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
Update: haven't found a rod yet mostly b cuz I've been sitting on my ass and working, now I'm on a 2 week break so I have plenty of time to find me a rod. Also just calculated the price of this whole project including everything I've bought and will buy and it's "only" $1460, which if that's how much this will cost said and done will be awsome so I can say "i got a 70cc that make close too/equal the power of the alx 71cc!" Take that for bragging rights ? but I'm not Gunna brag yet cuz it's still a crankcase and a bunch o parts ?
 
Just thinking about the fuel stuff and I'm going to get 2-5 gal of 100 octane, 2-5 of 112 octane, and 2-5 gal of e85 and see which runs the best, if all of them run like ass I'll buy a adjustable CDI so I can mess around with timing and rev limiters. Does anyone know about cdi's? Like which type to buy ?
 
Actually, I was advised by a bunch of dudes who was helping me with my fuel situation and I think I'll just buy a adjustable CDI, and if any 1 cares to help, wire it in and pick e85 OR X98 and tune the timing and afrs to e85/X98 and stick with it instead of risking getting detonation and melting a hole in my piston. I aksed around and bunch of peeps said that if I run 93 pump gas in it I'd have to retard the crap out of the timing and loose a bunch of power and it still don't running right so I'll use E85 OR X98 and just tune the ignition for that since it's cheap and good. Did I mention e85 AND X98 give a boost in power? Well it does, and who doesn't love extra power that you'll never use?
 
I'll be learning here, haven't seen a cdi yet on one. I'll be watching lol. Good fuel choices, I'd stick to 100 octane or what's local and tune for that. Power difference will be minuet.
 
John Parks said:
I'll be learning here, haven't seen a cdi yet on one. I'll be watching lol. Good fuel choices, I'd stick to 100 octane or what's local and tune for that. Power difference will be minuet.
Click to expand...
Yeah probably won't notice a difference between e85 and 100 octane. But I will notice a difference in money in my pocket! I want to do e85 cuz it's cheap and local, my fuel system is alcohol/e85 proof and I will Purge the system with normal eth free fuel to clean it out after each run to make sure it don't corrode anything ? the CDI I will need cuz the timing is not present being this is a custom motor, rcmax/alx have theres pre set and know what it's supposed to be, I don't so I'll need a CDI to mess with tha timing.
 
You better get a decent timing light and a degree wheel. I personally wouldn't bite for the Cdi ignition yet. You should be able to get offset keys for the flywheel to change timing. But at any rate your going to need to figure out where your at now. To be able to accurately change the timing.
 
Seandonato73 said:
You better get a decent timing light and a degree wheel. I personally wouldn't bite for the Cdi ignition yet. You should be able to get offset keys for the flywheel to change timing. But at any rate your going to need to figure out where your at now. To be able to accurately change the timing.
Click to expand...
I'll get the light and stuff. The problem is even if I know we're the timing is at I don't know we're it's supposed to b since it's a custom motor and all. I want to get the CDI and all b cuz I have to solder the ignition and I'd rather solder once then un soldering and all that. Plus if I get the CDI and my timing works fine then I just have another adjustment which is great if I want to try different fuels ?
 
Yeah I guess I can see that... I'm sure someone in here that has a custom engine can give you a starting point. My general guess would be to start around 20* BTDC and see how she does. if she ping just keep retarding the timing. I also would think you will be ok with timing at 100 to 108 octane at 14 to 1 compression. It just gonna take a little time to figure out where she needs to be set at.
 
Seandonato73 said:
Yeah I guess I can see that... I'm sure someone in here that has a custom engine can give you a starting point. My general guess would be to start around 20* BTDC and see how she does. if she ping just keep retarding the timing. I also would think you will be ok with timing at 100 to 108 octane at 14 to 1 compression. It just gonna take a little time to figure out where she needs to be set at.
Click to expand...
Yeah, I wanna run E85 cu it's cheap and local vs 100-108. But 100-108 would be better, but not local like I said ? maybe down the road if e85 issa PITA I'll switch to 100-108.
 
dougstar said:
It get more complicated as the day wears on:facepalm::rolleyes: well z you gonna need a medals when you get the beast all working :woot:(y)
Click to expand...
?? I know, gets more complicated and more money but plugging along, trying to make sure I don't have any/least amount of problems when I first run it, down want it to blow up or melt a hole in the piston. NOT Gunna quit, I will make this run no matter the cost cuz it's been too many hours of planning, too much money, and too much time of the truck broken, if I quit I've bassically thrown all my money and a years worth of time in the trash which is NOT happening, don't care who tells me it wont work cuz ILL MAKE THIS female dog WORK DAMNIT!!!!!!!!
"well z you gonna need a medals when you get the beast all working :woot:(y)" thanks man ??
 
Well, mighta found me a rod, it's for a Honda Mb50, it's 13.5mm wide (the crank ALX uses has a 13-14mm rod so I'm fine there), 16mm big end pin, 12mm small end, that only problem with this rod is (knew that was comin huh?) I need to know how thick the center section is so I can make sure it will clear the inside of the crank webs. I sent a email to sum peeps who sell it should geta reply in the next 24Hours hopefully. I wanna try to find a CDI but right now I feel like poop because I've cought a cold or gotten allergies (again) I dunno, soar throat, mild headache, don't feel like moving ???? hopefully will get better soon ? ?
 
crucialRC said:
That's good to hear about the rod.(y) How much? I cought a cold or something also.:confused: Been sneezing and coughing for like 3 days. Sucks to be off until 1/2/19 and be feeling like :poop:
Click to expand...
How much fir what? The rod?
" I cought a cold or something also.:confused: Been sneezing and coughing for like 3 days. Sucks to be off until 1/2/19 and be feeling like :poop:" yeah it sucks!!!!
 
Back
Top
✖
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock    No Thanks