Custom 70cc engine build

Is it worth it or stupid?

  • YES

    Votes: 21 63.6%

  • Hell no

    Votes: 2 6.1%

  • Kinda

    Votes: 4 12.1%

  • YES

    Votes: 3 9.1%

  • Nah I'll pass

    Votes: 3 9.1%
  • Total voters
    33
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Well I do not have enough time or beer to go back 40 pages or so , What are you waiting for to tie up that motor so ya can light a fire in it. Did something bad happen along the build to hit a wall !
Seandonato73 said:
Its stainless and teflon kinda goofy looking. Should have taken some pics of it with out the paper tab on it. Walbro states impervious to ethanol. I guess I'll see.
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see this is where its get goofy, Is it ethanol proof ? yes at pump e85 street racer crap. The 54 gal drums of Sunoco METHANOL we use is a whole different fuel. funny car fuel ! not e85 weekend warrior at the pump stuff.
 
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lorraine said:
Well I do not have enough time or beer to go back 40 pages or so , What are you waiting for to tie up that motor so ya can light a fire in it. Did something bad happen along the build to hit a wall !

see this is where its get goofy, Is it ethanol proof ? yes at pump e85 street racer crap. The 54 gal drums of Sunoco METHANOL we use is a whole different fuel. funny car fuel ! not e85 weekend warrior at the pump stuff.
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Thread repair is the issue, still waiting.
 
put a tee pocket sleeve in that and NOT cheap ass heli coils. The tee pocket sleeve will put all the face load on the tee top counter bored flush to repair surface and pull up to the mating gasket surface on joining part .
 
Hey I'm just telling you what their websight says take it how you will. E85 or any alcohol based fuel is extremely hydroscopic. I've used straight methanol in engines and had the same issues. Our race boat ran a methanol, nitro set up. That was on an old 2.3l black max mercury. Direct port nitrous over a 20% nitro 80% methanol for fuel. So don't lay the weekend warrior crap e85 vs methanol. Same issues with either fuel.
 
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Seandonato73 said:
Hey I'm just telling you what their websight says take it how you will. E85 or any alcohol based fuel is extremely hydroscopic. I've used straight methanol in engines and had the same issues. Our race boat ran a methanol, nitro set up. That was on an old 2.3l black max mercury. Direct port nitrous over a 20% nitro 80% methanol for fuel. So don't lay the weekend warrior crap e85 vs methanol. Same issues with either fuel.
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I was not jumping on you , I just was saying that the e85 blend seems to be alot easier on fuel systems. I seen methanol mess things up bad in under 9 hours and a street bike running e85 all week and not have any happen but water build.
 
It doesn't matter to me what the spiral diaphragm is resistant to to me uonestly cuz i'm Gunna change to bigger 25mm methanol carb, so I won't be running this carb for too too long.
 
Mkay question for you guys. Got it all together and went to start it, and it will not start. It will make pops and bangs and will poor a bit of smoke out the exhaust but just won't start. It sounds like a idle type of thing but sometimes I blip the throttle while turning it over it doesn't change. Just more pops and bangs and smoke. So I'd appreciate some help.
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Maybe should I try charging my ignition battery some more? I know it has charge in it but I don't know how much.
 
Z.hb71 said:
Mkay question for you guys. Got it all together and went to start it, and it will not start. It will make pops and bangs and will poor a bit of smoke out the exhaust but just won't start. It sounds like a idle type of thing but sometimes I blip the throttle while turning it over it doesn't change. Just more pops and bangs and smoke. So I'd appreciate some help.
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Maybe should I try charging my ignition battery some more? I know it has charge in it but I don't know how much.
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Timing maybe? Backfires usually points to that in 1:1 anyways.
 
D3MON said:
Timing maybe? Backfires usually points to that in 1:1 anyways.
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Can't adjust idle timing, it's always 5 degrees before tdc. The timing I can adjust is top of the rpm range I believe, and it starts at 5deg and advances up that way. And it's not backfiring, it's popping like if I had the choke on, just for a shorter duration
 
Z.hb71 said:
Can't adjust idle timing, it's always 5 degrees before tdc. The timing I can adjust is top of the rpm range I believe, and it starts at 5deg and advances up that way. And it's not backfiring, it's popping like if I had the choke on, just for a shorter duration
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Is the plug gap good ,also ,have you tried starting it with the filter off?
 
cbaker65 said:
Is the plug gap good ,also ,have you tried starting it with the filter off?
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don't know about the plug gap it's what its set at from ngk. I will try without the filter. Tomorrow.
You know what else it could be? Maybe it could be my spark plug is too cold. I'm running the coldest plug out of the three so maybe I should try a warmer one?
 
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Z.hb71 said:
don't know about the plug gap it's what its set at from ngk. I will try without the filter. Tomorrow.
You know what else it could be? Maybe it could be my spark plug is too cold. I'm running the coldest plug out of the three so maybe I should try a warmer one?
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Does the engine have a ton of compression ,an new ,if so ,try loosening up the plug on your first starting ,
also ,a lot of compression ca collapse the plug gap!
 
I would also look at timing, but 5* retarded should fire it up. Plus if I'm not mistaken that cdi fires twice at low rpm to help improve start up. Also check to see if your getting a good signal with your test tool for the cdi to fire. Charge your battery as well. These systems are forgiving but work best at a certain voltage. I assume your test firing on regular gas and not e85? Next are you sure your getting enough fuel for it to fire? And have you set the idle stop open a bit?
 
Seandonato73 said:
I would also look at timing, but 5* retarded should fire it up. Plus if I'm not mistaken that cdi fires twice at low rpm to help improve start up. Also check to see if your getting a good signal with your test tool for the cdi to fire. Charge your battery as well. These systems are forgiving but work best at a certain voltage. I assume your test firing on regular gas and not e85? Next are you sure your getting enough fuel for it to fire? And have you set the idle stop open a bit?
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I'm doing it on e85, should I try pump gas I'm getting fuel, I tried putting a tiny bit of fuel down the plug hole and it does the same thing, pop pop pop but doesn't stay running. I raised the idle a bit but maybe I should do more
Seandonato73 said:
Did you get your compression gauge? It may be pinging.
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How would the compression gauge tell me if it's pinging?
 
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