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Old 09-09-2008, 04:59 PM
TheListenMission TheListenMission is offline
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Join Date: Aug 2008
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Default replacement parts

I am getting ready to embark on a trip through miles and miles of nothing, riding with one of the China motors. I was wondering if you all had any suggestions for what extra parts would be best to bring along.
And with that, what kind of CDI should I buy in case mine dies? I know very little about these.
I am also having trouble getting my chain to act right. I think my sprocket is a little lopsided. The chain will be slapping, and I'll move the idler pulley about a mm up, and then it feels too tight periodically during a full wheel rotation. I have been trying to find a spring-loaded roller or tension-er of some type in hopes that that will help solve the problem. Any ideas? I'm not near any TSC's and the dirt bike/ motorcycle shops never know what I'm talking about.

Anyway, any suggestions on crucial things to bring along would be most appreciated.

Thanks a lot,

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Old 09-09-2008, 05:25 PM
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wheelbender6 wheelbender6 is offline
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Location: TX
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Default Re: replacement parts

There is a post on this site where a guy made his own spring-loaded tensioner out of a coaster brake arm. Also, bike shops (and EBay sellers) sell spring loaded chain tensioners for single speed bicycles that clamp around the chain stay of your frame. That may cut down on how often you have to adjust the tensioner that came with your kit.
Check your chain carefully to see if there are any bulging, stuck or bent links. That could cause the chain to wobble off of perfectly good sprockets. It's easily fixed with a chain tool or a bicycle shop can do it. Good luck.
“You're only young once, but you can be immature as long as you like" -Unknown
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Old 09-09-2008, 05:43 PM
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Dave31 Dave31 is offline
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Location: Old Pueblo,Arizona
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Default Re: replacement parts

I have taken some very long rides.

The only "extra parts" I carry is a spark plug, and a spare chain link.

I always carry a extra tube and pump, and plenty of tools to do almost anything on the bike.

I did have a throttle cable break on a 140 mile trip one time. All I did was pull the shielding off and used the remainder cable as a pull string to work the throttle.

I do have a spare CDI and Mag which I got from.... I have never carried them with me on a ride but if you have them why not?

If you are running the stock chain that came with your is JUNK! It will stretch and stretch forever. Most of us will replace the stock chain with a good quality #41 chain........

I've been using my stock tensioner for five years and over 4,000 miles with no problems
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Old 09-09-2008, 09:18 PM
TheListenMission TheListenMission is offline
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Join Date: Aug 2008
Posts: 3
Default Re: replacement parts

Thanks for the responses!

After searching the forum for answers to my oblong sprocket, I am still confused. If the center of the sprocket is indeed off-center, what should I do? I would hate to put more money into this thing and buy one of the custom-made sprockets (not to mention post-pone my trip to wait for it to arrive).
I thought that maybe it's not off-center and I just installed it a little ot the side, but there is no space in between the center and the hub of the wheel.
Should I try to file out the center?
What to do...what to do...
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Old 09-09-2008, 09:42 PM
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mralaska mralaska is offline
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Location: Deerfield, NH
Posts: 42
Default Re: replacement parts

There are two ways you need to true your sprocket. I check mine by removing the motor chain so the rear tire can freewheel then brace a pencil against the chain stay and almost touch the sprocket as the wheel is spinning. You can see how much the sprocket wiggles and it will brush against the pencil on the high spots so you know where you need to bring it in with the sprocket bolts. It is hard to get it perfect but keep it under a mm.

As far as being on center, you can check the same way by tracing a line around the outside of the sprocket while the wheel is turning as close to the teeth as possible then if it is off you can easily see where you need to hog it out. You can draw an sixteenth inch line on the side of the center that needs to be moved then grind away with a dremel. I would not mess with it unless the deviation is unmistakeable.

50cc Slant Head mounted on a $5 Huffy mtn bike

Last edited by mralaska; 09-09-2008 at 09:45 PM.
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Old 09-09-2008, 09:43 PM
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Spunout Spunout is offline
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Join Date: Jul 2008
Location: coventry, RI
Posts: 475
Default Re: replacement parts

unfortunately, we're all at the mercy of Chinese "quality control" (or lack thereof). a problem i have seen many times, is sprockets are warped. imagine holding a frisbee between your twist each hand opposite ways. yep. like that.

about the only remedy i have found, is filing/grinding down the outer edges of the teeth. to the point that the sprocket looks like a regular bicycle crank.

sprocket alignment/centering is touchy, sometimes. thew best advice i can give, is just keep messin' until it's right.

as far as CDI and such....just get the least expensive you can find. THEY ARE ALL THE SAME. as with many parts.

parts interchangeability is a cinch.

i carry all the tools/parts just short of an entire motorkit with me, wherever i go. most items have been used at least once, during my travels.

fairracing is correct about stock chain-stretch. its alot.
if you DO get a #41 chain, dont be frightened the first time you fire it up....the wider #41 chain may rub on the casing for a little bit. its harmless. it'll rub itself down and shush.

EDIT:mralaska caught me with me pants down....i was thinking lateral problems, not orbital. sorry.
Originally Posted by Dan View Post
Originally Posted by Bikeguy Joe View Post
You are one sick man spun, I like that quality in a person.

Last edited by Spunout; 09-09-2008 at 09:47 PM.
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Old 09-10-2008, 01:00 AM
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ebmvegan ebmvegan is offline
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Join Date: Jul 2008
Location: OC, Ca
Posts: 284
Default Re: replacement parts

I've purchased some of my parts from Live Fast Motors . Their clam shell sprocket adapter and spring loaded chain tensioner works great. They ship fast, so if you have a week before the trip, give them a try. As for carrying spare parts, make sure you carry extra cables with you. If the throttle breaks, you're not going anywhere and the reverse for brakes. Even on short trips I carry a bottle or 2 of 2 stroke oil in case. Carrying enough tools to fix anything on the bike is a no brainer. We don't want to see a post saying they had to push their motorized bicycle back all 100 miles. Good luck!

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