schwinn stingray .

ok guys, i got my engine kit and exhaust and mount the same day, i thought the exhaust would just look cool but with the stock pipe your only option was to have a smokestack, and i didnt want to suffocate..but after many hrs of working me and my dad got er put together and she looks bad azz (at least to me) ill have tons of pics and vids later today, my dad had 2 work today and he wants to see its madien voyage, he gets home in 20 min. he seems thrilled with it :D i flattened out the idler pully bracket and ground off the corners the corners cause if i stuck my foot 2 far back i would rip it up and i heard tons od posts abot twisting pullys on square bars, well anyway ill explain it all in the pic and vid sections later today. im thrilled with the way it turned out.
 
bike is completed and running i need to get a bigger o-ring for the carb though it wont idle... whis thing is wayyy to loud i just got the hearing back in my left ear (not kidding) i will put the pics up in my pics and when it is up ui will post the vids in mbc tume thanks.
 
OK guys it seems like this bike is giving me more problems then my 1st build you'd think it would be the other way, but anyway to the problem,Ive been doing some searching but no one seems to have the same EXACT problem as me. the 1st day i had it i had the seal in from the get go, but i guess i had the wrong size, so i went back today and got a seal that looks like a rubber in a garden hose you guys recommended it. but now i got it running and it will only IDLE at 3/4 choke and when i do sorta get it to idle with the choke open it acts like the throttle is sticking the 2nd time after i get it idling , but i am positive its not sticking, any ideas this is confusing, and i sorta want to fix it today and i cant ask my dad for help cause hes doing a double, 6am-11pm..... oh and i doubt its the idle screw cause ive moved it from all the way closed to 5 turns open going mby 1/8'ths
 
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hey guys i fixed the problem, the engine was tilted 2 far back causing the carb to flood :)
 
needle bearings versus bush

Hi, I read that stuff about needle bearings and bush bearings. I always thought that the needle bearing engines were better until recently when I've been getting longer engine life out of the slightly cheaper bush engines. The bush ones are noticeably quieter as well and definitely vibrate less. I'm talking about the 66cc lagest chinese motor.
So now I'm buying the cheaper bush motors but with the same kit as the needle bearing motor cos it is a slightly superior kit - better exhaust and thicker metal clamp for the rear mount. This has been my experience from riding 14000 kms. Wonder if anyone has had a similar experience.
 
my problem is this mornin my bike was running fine i hit 100mi today well this afternoon i hit anything above 16 and my butt pretty much vibrates off this never happened before i know there are alot of vibrations threads bun no one seems to have the same issue as me (not being that bad then the next time u ride ur butt vibrates off) any suguestions? i already have the fat a** seat... if this is normal i am taking off the engine i cant stand this. its worse than sitting on a harley with no suspension.:censored::mad::confused::sick::-|:cry::-/:eek::???:

When I've had this happen (severe vibrations) it's always been cos a rear mounting bolt has just snapped except on 2 occasions when there was a damaged piston ring or scored cylinder (noticeable increase in vibration) and I know when this happens because the engine revs don't die down as fast when I open and close the throttle. If the cylinder is seriously scored I get another engine. When the piston ring is faulty I've found it was caused on both occasions by poor engineering - the groove for one of the rings was not engineered to the correct depth so the ring wouldn't close and this eventually scored the chrome cylinder. Not really worth fixing. If you buy several engines you'll get some good and some bad. I've had more of the latter. I've presumed that you have eliminated the obvious causes of severe vibration like bad engine mounts, loose saddle or post etc. Hope you get it sorted.
 
Hi, I read that stuff about needle bearings and bush bearings. I always thought that the needle bearing engines were better until recently when I've been getting longer engine life out of the slightly cheaper bush engines. The bush ones are noticeably quieter as well and definitely vibrate less. I'm talking about the 66cc lagest chinese motor.
So now I'm buying the cheaper bush motors but with the same kit as the needle bearing motor cos it is a slightly superior kit - better exhaust and thicker metal clamp for the rear mount. This has been my experience from riding 14000 kms. Wonder if anyone has had a similar experience.
I understand that most motorcylce engines use a roller or ball bearing setup for the crank and con rods.
I don't know why this would create vibration, but bearings like that actually have a smaller surface area to support the crank, so it actually sees more stress.
This is why cars use sleeve bearings and pressurized oiling systems.
The crank and rods actually ride on a thin layer of pressurized oil, lending to better support of those items and less resistance to rotation.

Why someone can't design a small engine in the 25cc-50cc range that uses this bearing/oiling system is beyond me.

Anyway, in case you're still curious about what a needle bearing is, I've attached a pic of one (marked "kit786-1").

The other attachment shows a sleeve bearing.
It's actually 1/2 of a thrust bearing from the crankshaft of a car engine, thus the flanges. Those keep the crank of going too far fore or aft, in the block.



Dean
 

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thanks to everyone. i forgot about this thread lol but john, i am gonna pretend ya didnt say that, cause i dont got the money for a new engine lol. ive gone 100mi+ since i posted that. my butt still hurts, but my hands dont anymore, cause my dad brings home tons of pairs of work gloves, and i just cut the fingers out and i cut some holes in the top, so theyre like bike riding gloves, but my hands are too big for those. but since theyre rubber, i font have problems anymore. thanks again everyone! off to install a front suspension fork from my mtn bike!
 
thanks to everyone. i forgot about this thread lol but john, i am gonna pretend ya didnt say that, cause i dont got the money for a new engine lol. ive gone 100mi+ since i posted that. my butt still hurts, but my hands dont anymore, cause my dad brings home tons of pairs of work gloves, and i just cut the fingers out and i cut some holes in the top, so theyre like bike riding gloves, but my hands are too big for those. but since theyre rubber, i font have problems anymore. thanks again everyone! off to install a front suspension fork from my mtn bike!
If you can find a piece of rubber pad (maybe an old welcome mat?), cut a couple of small pieces out of it and see if you can't incorporate them into your motor mounts.
That's what Harley did and the car makers have been using them for years.
Should make for a much smoother ride and your butt will love you again. ;)



Dean
 
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