Something CRAZY going on.

[Flyman]

Guy,s I almost had my build done I thought.But this crazy chain
deal is killing me.I,m one link away to driving this thing.But if I
leave it as is, then it,s two long.If I take a link out it to short.

I would have thought the tensioner would adjust it out.But it's
still to long.I wonder if I leave the master link out & make a soild
chain if that would help.There must be someone who has run into this
before.

Fly

 

[YesImLDS]

If it's too long take off a link using the proper tool or I personally use a dremel and grind one off.

 

[Chainreaction]

Half link

 

[YesImLDS]

I'm sorry I didn't understand the problem go with what he is saying.

 

[Flyman]

Ya I think the half link would solve the problem.Man I never would have
thought one link could cause so much trouble.Where can a guy
buy half links local. I guess I,m asking what type of store would sell
them for this size chain, 41 I,m thinking?

Fly

 

[Rudz]

Stock chain size is 415

 

[Flyman]

Will a #41 half link work?I found Tractor Supply has some & I
would like to get this thing running tomorrow if possible.

Fly

 

[Chainreaction]

If not break out the grinder and the hammer.

 

[crassius]

41 1/2 link may not go all the way thru, but you could pick up 41 chain to go with it

not sure why the tensioner can't be moved forward or backward to take up slack for you

 

[Flyman]

(QUOTE)not sure why the tensioner can't be moved forward or backward to take up slack for you? Me ether? but when I remove 1 link it,s just too tight for the master link.If
I add a link the adjuster puts it almost to the top chain.

Any way I,m going to just buy a 41 chain, a haft link & a master link.Come he11 or
high water I,m going to fix this deal.

Thanks Fly

 

[The_Aleman]

<removed out of protest to certain "staff" practices in this forum.>

 

[crassius]

assuming you already put a piece of PVC between rear motor mount & frame, you could put a 2nd piece in there to get the chain a bit tighter (I've never built a bike without that PVC to keep from breaking frame there)

 

[crassius]

just realized that you may not know that these new chains will stretch about 1/2in within first 10 miles or so - you might try to run it a while, then remove some slack after it stretches

 

[KCvale]

assuming you already put a piece of PVC between rear motor mount & frame, you could put a 2nd piece in there to get the chain a bit tighter (I've never built a bike without that PVC to keep from breaking frame there)

You put plastic between your engine and seat post!?
Umm, let's just say that I have found anything but direct metal to metal at a 90 from motor to seat post angle is a failure waiting happen.

... like a piece of plastic is going to keep a cheap frame from breaking with a chain bind failure anyway hehe ;-}

If you can move the engine up or down any that can help but as mentioned the stock 415 chain and sprockets loosen up big time with little mileage.

I have tips for how to do this but I need to see your setup, like horizontal vs. vertical dropout and your motor mount system.

1/2 links are cool for really hard fits but no, 41 chain 1/2 links don't play nice with 415 chain, the roller holes are a differ size and as mentioned, that cotter pin, and the room inside your motors output gear clutch cover.

Plastic 'strength' mount... sorry crassius, a steel sleeve maybe to move the engine forward but really?

Just for giggles and grins, take a bike with some miles and grab the top bar with one hand, and the top of the engine head with the other, and shove them back and forth as hard as you can.
If they move AT ALL it is a fail just waiting to happen.

 

[crassius]

PVC isn't your usual plastic. It will form itself to a perfect fit and provide more static friction than a metal to metal mount.

Hard leather seems a bit better, but takes forever to seat in.

 

[YesImLDS]

The stock tensioner also has two different ways to be adjusted via the pulley itself and the position on the frame. Is there no happy medium when using it that way? I remember when I was a link too short and it wouldn't work, but when I added a link it fit just right even before adding the tensioner. You could try putting the chain half onto the rear sprocket itself and putting the chain together then rolling bike backwards to jump the chain onto the rest of the sprocket as well

 

[KCvale]

You could try putting the chain half onto the rear sprocket itself and putting the chain together then rolling bike backwards to jump the chain onto the rest of the sprocket as well

Just a tip:

There is spot in most spoked wheels where there is gap big enough to fint your hand in.

Roll your wheel so the spot where your spokes are parallel and you can fit your hand behind the sprocket all the way to the back.

Pull out the spark plug.

Feed you your chain up from the bottom of the motor sprocket turning clockwise on the sprocket retaining nut.
Trying to run the chain the other way will loosen the nut.

Feed the chain until the top side end is draped over the sprocket and will hold, and turn the wheel to take out the slack.

Run the bottom part of the chain up with no tensioner and get it as close as you can using the bottom of the sprocket to hold the chain, and see what you have.

When you have the chain ready put the mater link's long side in from the back, the plate and retaining clip on the outside.

Besides having the sprocket do the hard work, it's pretty easy to find a master when the clip is on the outside.

 

[graydog8josh]

41 half link on a chinadoll might be a problem because many 41 halflinks use a tiny cotter pin to hold the link in.
This cotter pin may not clear the chain run inside the engine output.

The frame-mounted idler should solve any chain-length problem, but if not, then running the proper 415 chain should.
Some people here use no idler/tensioner. If you need an exact length of proper-size chain:

415H chain: www.amazon.com/KMC-415H-3-16-Black/dp/B002DMWEAM/
415H half link: http://www.amazon.com/KMC-Bicycle-Chain-Half-Link/dp/B00HZ8PAQY

ive run 41 chain with no problems for 2 years on five engines with half links. i get my chains from tractor supply too

 

[graydog8josh]

also i extended my chain tensioner about an inch and a half and when i found the height it needed to be i welded the slot up into a hole just big enough for the tensioner bolt to go through

 

[Flyman]

Well I got some 41 chain from Tractor supply & adjusted the rear wheel
in just a tad & locked it down with out using a tensioner. It is a tad & just a tad
tight. The regular bike chain just a tad lose but all seem good for now.

I like the #41 chain much better.A little smaller over all give more clearance
from the frame also.

Fly