welding crank arms

[arkives1]

chain tensioners

Hello Al, another late night for me.
It's not my design, I can't take credit, but it is a good idea.
I've seen the spring tensioner from Tractor Supply. It looks good. Trouble is, they have no distributors here, as far as I know and postage from the states is murder. I've bought a sprocket, a 3L tank and a sprung gel seat lately and each time delivery was about $US40-45, ($AU45-50). My seat was $US26.95, but postage was $US45.90.
I would prefer sprockets to rollers, too, but the rollers seem OK so far.
I need the main (fixed) tensioner, then a small guide on the top chain run to stop it swinging side-to-side too much or it touches the frame lightly.
Also, due to rear sprocket runout, I need a spring tensioner on the bottom.
If I adjust the chain with the wheel turned to where the chain is tightest, it gets pretty loose when the wheel turns 180 degrees. The spring tensioner will alleviate that.
(For anyone interested, I have quite a collection of tensioner pics, must be about a dozen or so types, collected from this site.)

I'd be interested in those pics Steve and Thanks for the offer.

 

[AussieSteve]

If you can get the chain just the right length maybe you won't need a slot.

On my frame and many others, the wheel can't be moved to adjust the chain as it wears/stretches, so an adjustment slot is unfortunately necessary.
I'm thinking about adding a small cross-piece with 2 screws, so that it can be placed hard up against the bottom of the rolle rnut and clamped so the roller can't slide down the slot if the nut works slightly loose. Can you picture what I mean?

I do like the idea of a spring pulled roller though. I agree that the offset design doe's tend to pull the thing into the spokes. I've had that happen and had to replace a whole wheel on my cruiser. It also brought me to a sudden stop and I laid the bike down luckily not damaging anything else (including me)

I read a few sad stories about the tensioner pulling into the spokes. You too.

If memory serves me right, the one I showed was meant to pull up on the top chain to prevent chain jump when slowing down and the chain is being pushed into the engine rather than pulled through by the engine itself. I'd think if the lower chain tension was right, it would keep the top chain straight too. I'd need to look at the chain as I slowed down to see what it's doing, personally, I prefer to see where I'm aiming the bike. Ive found that if I can get the chains on both sides just right, I don't need a tensioner with rear drop outs. I can adjust the tension on both sides with wheel movement.

Lucky

Unfortunately though, of my three bikes, only the chopper has rear drop outs and that bike presents a whole new challenge in tensioners.I hopefully have solved that problem with my occ choppers tension set up as it cannot twist since the frame is square shaped tube.

I have a friend in the US, an MBc member, who is still trying to get his chain set up on his OCC chopper after several weeks. It sounds like they're not too much fun to set up. Still, they look good. I have a couple of pics here.

The designs you guys have would also make it very easy to attach a chain guard and keep it out of the chain, top and bottom. I'd prefer top and bottom guards on the chain. Imagine your pants leg being pulled into the chain at 30mph. Among all the clever, creative people we have on this forum, we're bound to find solutions.

Haven't fitted a chain guard yet, but I did buy a pair of skinny leg Levis for riding. They may look a bit silly, but no worries with chains.

... Steve

 

[arkives1]

welding cranks

Steve I sure can picture what you're thinking of.. maybe one of the rear wheel chain tensioner that attach to the axle could be rigged to pull down on the roller bolt?

 

[AussieSteve]

I'd be interested in those pics Steve and Thanks for the offer.

I won't clutter this thread any more with them. I'll start a new thread in 'Frame-Mounted.... titled 'Chain Tensioner Examples' and post the pics there.
Regarding anything electronic for these things, I'd be very interested in ideas. I'm thinking about a tacho, but would enough people be interested?
I still have everything needed to design and make 1-offs and small runs of circuit boards and pretty good electronic design and simulation software. (And plenty of spare time as a pensioner)
Ideas anyone?

... Steve

 

[AussieSteve]

Steve I sure can picture what you're thinking of.. maybe one of the rear wheel chain tensioner that attach to the axle could be rigged to pull down on the roller bolt?

Here's a rough sketch of tensioner with roller lock:-

 

[arkives1]

Here's a rough sketch of tensioner with roller lock:-

Steve,
That design for locking the roller bolt looks feasible. Steel or aluminum?
As for ideas for electronic/electrical devices, how about turn signals that have the control mounted by each hand, ie: left signal by left grip etc. A brake light/tail light combination would be nice. I have one from Dinodirect.com that works but the controls are all on one central handle bar mounted box. They work reasonably well and the brake light works ok but won't work with coaster brakes. These things are cheap and not that well made but for the price they do the job. I live in the city and many of the drivers here will not know what the hand signals are supposed to mean. I've had cars pass me on the left as I was turning left, and one that nearly ran me down from the rear when I slowed to stop at a traffic light. The ones I have only signal to the rear, to the front would be nice too. there is a flat rubber pad under the outside clamping plate
For your friend who's doing a chopper and has difficulties with the tensioner, I've attached some photos of mine.Perhaps he can use it or work further and improve it.

 

[AussieSteve]

Steve,
That design for locking the roller bolt looks feasible. Steel or aluminum?
As for ideas for electronic/electrical devices, how about turn signals that have the control mounted by each hand, ie: left signal by left grip etc. A brake light/tail light combination would be nice. I have one from Dinodirect.com that works but the controls are all on one central handle bar mounted box. They work reasonably well and the brake light works ok but won't work with coaster brakes. These things are cheap and not that well made but for the price they do the job. I live in the city and many of the drivers here will not know what the hand signals are supposed to mean. I've had cars pass me on the left as I was turning left, and one that nearly ran me down from the rear when I slowed to stop at a traffic light. The ones I have only signal to the rear, to the front would be nice too. there is a flat rubber pad under the outside clamping plate
For your friend who's doing a chopper and has difficulties with the tensioner, I've attached some photos of mine.Perhaps he can use it or work further and improve it.

The lock plate should be steel, I would think. It's stronger and harder. For the bolts to hold the plate, I have 5mm x 20mm high tensile bolts and nuts so I'll use them. That roller won't be going anywhere, (I hope).

My friend with a chopper is, hope I've got his username right, billpb1222.
I just emailed him to see how he's going.
I couldn't imagine anything worse than getting most of a build done but being unable to even start the engine due to drive-train problems. I wouldn't be able to sleep 'til it was sorted.

The biggest problem with brake signals is coming up with something universal for switching them. Nothing really beats a motorcycle brake lever with integral brake light switch for that. Otherwise, trying to set up a microswitch just right can be difficult.
Indicators aren't too hard, but would draw too much current for these engines, (white wire), unless LEDs were used. I'd use a LED brake light, too.
I picture a 5V set of 4 x Ni-Cd or Ni-MH cells for power, trickle-charged by the white wire. Not much power is available.
I'll probably do a tacho first, for fun, then see what else develops.
I have hall effect sensors, small microcontrollers, Ni-MH cells and 16-character LCD displays already sitting here, so that one almost makes itself. I can just sit here and watch.

... Steve

 

[AussieSteve]

arkives1, I just checked out your pics of the chopper chain setup. I notice that like others I've seen, you run the chain under and not over the fork/chainstay and the rensioner hangs below.
Can't it be done the usual way on these frames? ie Above the chainstay, with the tensioner pointing upwards.

NB. I'll pass your pics on to Bill to check out. He's had heaps of little problems getting his set up.

... Steve

 

[Al.Fisherman]

Steve..Looks like if the tensioner was reversed there would be brake cable issues.

 

[arkives1]

Steve..Looks like if the tensioner was reversed there would be brake cable issues.

Steve, Al is correct, the brake presents an obstacle and depending on the size of the sprocket used, the horseshoe shaped rear frame becomes another problem. I have seen some done with the chain going over the top of the frame. I'm told that they push the engine as far to the rear as possible and as high as possible. Raising the engine and moving it back then puts the carb up against the frame or so close the cable to it is crimped. One solution to that was an extended and angled intake manifold to move the carb toward the pedal crank side of the engine. I've stayed with the 44 tooth sprocket for now because where I ride there are some substantial hills. I might be able to go to a smaller sprocket with fewer teeth if the bike handles the hills well. That would give me more top end speed of course. About the turn signals, the ones I have now are LED and run off batteries. I forget what size or how many though. They are quite visible especially at night. The brake light on that thing is activated by a microswitch with a hole thru it. A screw locks it onto the brake cable so that its compressed to the on position when the brake is used. Simple and fairly easy to adjust. A tach might be interesting as I'm sure we've all wondered what rpm our engines are winding out at. How useful that info is ...I don't know. If using a shifter and jack shaft it might be useful to know when to change gears, or knowing what your speed is at a given rpm would act as a speedometer of sorts. I don't know for certain that my chain tensioner will actually work, I haven't even had the engine started yet as I'm working in my home work shop so no gasoline fumes there. Its too cold to work in the garage where I usually work on these.