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  #1  
Old 02-25-2009, 12:37 PM
danajohnhill danajohnhill is offline
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Default Is a tensioner necessary?

The diameter of my bike frame is just a bit too small to keep the tensioner in place. It keeps moving around, causing the chain to pop off, or bind up. How bad would it be to take a few links out of the chain and run it without a tensioner?
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  #2  
Old 02-25-2009, 12:49 PM
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MB-Monkey MB-Monkey is offline
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Default Re: Is a tensioner necessary?

If you can manage to keep the chain off of the chain stay (the bar that runs along the bottom) running without a idler pulley (tentioner) would be ok my huffy is setup that way.

The other option would be to use a self tapping screw thru the pulley bracket and into the chain stay which is how mine was setup until the idler pulley fell apart.
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Old 02-25-2009, 12:50 PM
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2door 2door is offline
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Default Re: Is a tensioner necessary?

You'll find two schools of thought on this. Some will tell you that the tensioner isn't necessary and to get rid of it. Others, me included will offer that not having a tensioner will leave you little room for chain adjustment. The original chain, #415, supplied with most kits is known for premature wear and therefore loosening. With no tensioner to take up the slack you're left with what you can get from your wheel mounting area, (drop-out) and sometimes that isn't enough so then you're faced with shortening the chain and/or adding half links to get and keep the tension right.
If you decide on using the tensioner there is an easy fix for the tensioner bracket loosening or rotating on the chainstay. Drill a small hole completely through the bracket and bike frame and install a screw and nut, I use a 10-32 Allen head cap screw and locking nut. Others simply use a self tapping screw. Either way you must be sure your chain/sprocket alignment is correct before you secure the bracket to the frame and before drilling. A good many of us have abandoned the kit supplied chain for a good quality industrial chain, #41, available at Grainger, Tractor Supply and I've heard even Ace Hradware carries it. Let us know what you decide and good luck with your decision.
Tom
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Old 02-25-2009, 02:49 PM
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Default Re: Is a tensioner necessary?

another nice thing about the chain tenioner is it keeps the chain from falling off the sprocket when you make tight turns or go over lost of bumps.
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Old 02-25-2009, 03:37 PM
mekano mekano is offline
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Default Re: Is a tensioner necessary?

I think the tensioner is necessary when you first use the tacky, soft chain that comes with the kit. It stretches alot at first and it's more comfy to adjust a small tacky wheel than braking a chain a few times.
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Old 03-14-2009, 11:36 PM
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Default Re: Is a tensioner necessary?

If you're building a Schwinn Jaguar you have to do something to keep the chain adjusted. The Jag has no provisions for moving the rear wheel back. The dropout is just that, a dropout without a slot. I've always hated the looks of the kit supplied tensioner bracket. It's an eyesore and I didn't want one on the Jaguar so I fabricated the one pictured below. I made it from 1" by 1/4" flat stock, machined a slot in it and tig welded it to the seat and chain stays. I found matching paint at the hobby shop, Tamiya #TS-53, model car paint, and repainted the welds after smoothing with some body filler. I use skateboard wheels for pulleys. This set up assures that there will be no movement of the pully and should provide a troublefree way to keep the chain adjusted. I've only needed to tighten the chain on my old bike once in 700 miles but even so it's a good feature to have available.
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Old 03-15-2009, 09:03 AM
hammmike hammmike is offline
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Default Re: Is a tensioner necessary?

I clamped the tensioner clamps in a vise and bent them so they would fit the smaller tubes on my Huffy. Then I tapped a 10/32 hole and installed a socket head bolt. Works great.
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Old 03-15-2009, 09:27 AM
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Default Re: Is a tensioner necessary?

I always found the best thing was to adjust the wheel and chain with no tensioner then use it on the pedal side to take up the slack. That side is used a lot less and with much less torque and chain speed.
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Old 03-15-2009, 11:53 AM
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Norman Norman is offline
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Default Re: Is a tensioner necessary?

I like your bracket for your chain tensioner ought to be bullet proof.
My biggest problem is finding paint to match the bike if I weld on it. If I can find the right color paint the 2 bikes that I mounted the front engine bolt through the frame will get a tube reinforcement welded in when I can find the proper color even with the drilled frame I have not had any problems.
Norman
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Old 03-15-2009, 01:04 PM
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MB-Monkey MB-Monkey is offline
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Default Re: Is a tensioner necessary?

Quote:
Originally Posted by Norman View Post
I like your bracket for your chain tensioner ought to be bullet proof.
My biggest problem is finding paint to match the bike if I weld on it. If I can find the right color paint the 2 bikes that I mounted the front engine bolt through the frame will get a tube reinforcement welded in when I can find the proper color even with the drilled frame I have not had any problems.
Norman
Norman FYI a lot of the model car paints are very close to bike colors. I matched my huffy and a couple of mountain bikes fram colors up that way. Your local hobby shop should carry a good selection also the testors paint at walmart matches up at times too. Just a suggestion.
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