Almost giving up on my first 4-stroke build

[PsychDoc]

Hey thanks for all the replies. So I grabbed some calipers and measured the rear hub. I don't know exactly how to use these calipers but if I'm reading it right the hub is 1 and 1/10th U.S. inches. (living in united states btw to answer your Q) The real problem arises from the fact that going up to the spokes is a sharp inverted cone slope on the hub. (if that makes any sense). So the diameter climbs up to around 2 inches by the time it gets to the edge of the hub. So to get one of those adapters to fit I've realized I'd have to cut a reverse cone into the aluminum of the adapter. Sorry if that's a bit confusing.

Are there any place's I could get a rear wheel that has the standard one inch hub size? Before buying a new wheel or anything I'm going to try RB55's and Puck's suggestion of trying the original mountings again before I buy anything new. Might have to buy some better nuts and bolts but will definitely tighten to 12 ft-lbs. I might also try a larger, tougher chain as the one that came with it has a very tight tolerance with the sprocket.

Thanks all for the advice so far; I really didn't want to give up on this project as it was so much fun for just that little bit of riding. I will be selling that cnc sprocket on Ebay If I can't find a good rear wheel that works. But either way I have some renewed hope now about my bike project.

Not an expert by any means- but having pondered through rear sprocket questions- I believe the rear hub wants to be a ‘perfect’ cylinder. The reverse cone is a serious problem. So if the hub clamp paperweight is forced towards the center of the hub, sprocket alignment might be to far toward the center of the hub- perhaps a couple washers could move the sprocket outward?
Either way- you are close- don’t throw the project out the window.

 

[mark20]

dont give up man! these 4 strokes ride great when you get then figured out!

first thing id do is get a heavy duty chain, mine snapped on me the first time i rode it (it bent then snapped clean in half)

next thing is to tighten that sprocket down (yours looks very loose)
you dont really need a cnc sprocket for a stock engine, ive never had a problem with them (just be sure to keep them tight)

also, be sure to oil the clutch bushing, (if you dont it will seize up against the clutch and its a big pain in the ass to get unstuck, trust me)

also remember, half the fun is fixing these things!

 

[Idlandz]

So I went out today and bought #41 chain at the local tractor supply. A lot bigger and heavier duty. I'm trying the original sprocket again and with an impact wrench tightened it down in a star pattern as much as I could. I also made sure it was centered on the wheel hub. Tomorrow I'm going to try and put everything back together, hopefully it works out. I'll also oil the clutch bearing as it has been binding occasionally. (thanks for the suggestion mark) If it does work, merry Christmas to me, if not... oh well I'll try again.

 

[mark20]

So I went out today and bought #41 chain at the local tractor supply. A lot bigger and heavier duty. I'm trying the original sprocket again and with an impact wrench tightened it down in a star pattern as much as I could. I also made sure it was centered on the wheel hub. Tomorrow I'm going to try and put everything back together, hopefully it works out. I'll also oil the clutch bearing as it has been binding occasionally. (thanks for the suggestion mark) If it does work, merry Christmas to me, if not... oh well I'll try again.

Id also check clearances between the chain-tensoner wheel and the chain (as 41# is a bit wider the 415) if it rolls nice then itll be fine!

 

[Idlandz]

Alright so I did everything that was suggested on here and it's been working flawlessly now that the chain alignment is correct. I'm still nervous to give it any gas at all because I don't want to risk breaking anything. But I'm completely fine cruising at 20mph as long as the bike is working.

So thanks a ton to all the great member here who helped me out with great advice! I was really about to put the whole thing on craigslist as a basket case. I'll include some pictures of the finished project:

 

[mark20]

Alright so I did everything that was suggested on here and it's been working flawlessly now that the chain alignment is correct. I'm still nervous to give it any gas at all because I don't want to risk breaking anything. But I'm completely fine cruising at 20mph as long as the bike is working.

So thanks a ton to all the great member here who helped me out with great advice! I was really about to put the whole thing on craigslist as a basket case. I'll include some pictures of the finished project:
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looks good! congrats!

also, your fuel filter is on backwards

other than that, great job! you just fixed your own motorized bike!

 

[PsychDoc]

looks good! congrats!

also, your fuel filter is on backwards

other than that, great job! you just fixed your own motorized bike!

Agreed- it looks great
And if you’ve ridden it a bit without incident, you are not going to break anything.

And while the filter may be backwards- do NOT turn it around now.

 

[Idlandz]

Thanks! I'm painting the 7g transmission cover to match the red engine right now.

Yeah I was going to flip the fuel filter the right way but realized there's a bunch of trapped paint flecks and dirt that would be sent into the engine if i did. Oh well it does it's job backwards.

 

[Wrench]

Paint flecks and dirt in the fuel filter, Time for a new fuel filter and don't install it backwards.
The paint flecks come from the gas tank fill spout. When ya put the gas cap on it scrapes paint flakes off the top of the fill spout.
Clean out the gas tank, scrape off any paint from around the top of the gas tank fill spout.
Those cheep fuel filters don't last forever and your gonna get paint flakes in your carb.
This will hold the float needle open and gas will overflow out the overflow vent and or plug up the jets and passages.
Fix it before it happens.

 

[Gastrike 9]

Do yaself a good and throw that pineapple setup away... You're in for more headaches and a possible injury using those... Order yourself a CNC adapter, bushing and sprocket from Manicmechanic... It you don't see the size sprocket you want you can get the sprocket itself from mbrebel.com... I use these on all my hasbikes and trike... Also if you don't have one you need a good chain tentioner, spring loaded and not the cheap Chinese stationary crap... I blowed rear spokes 3 times using one of them pineapple jobeedoos... The 3ed time I ended up with some road rash on meself...