DIY motorbike turntable - any ideas?

[Dave H.]

Hello all,

I'm currently at the "design" stage for a garage to hold the family's selection of bikes (ranging from a Suzuki 125 to a 650lb Yamaha) and a few workbenches and tools (perhaps even a lathe...mmm...), one thing that might make life a lot easier as the garage wouldn't be that wide would be a turntable up the end that we could roll the bikes onto to turn them around (and it'd have a nice steam-railway air about it, too - perhaps it should be an "Engine Shed"[1], rather than a garage).

I'm so far thinking that it'll need:

1) recessing into the concrete floor to keep it level therewith (part of casting the floor slab, plywood form set in and levelled during the pouring process and weighted down to stop it floating away); 2) a centre bearing (perhaps a discarded steering head roller bearing?) to keep it centred, running between a plate-with-ring-welded-on bolted to the turntable and a piece of sutable bar conreted into the floor; 3) rollers (eg polyurethane skateboard wheels running in a circular track (cast in as part of the concrete floor) to take the load (possibly two tracks, one at the periphery and one 1/2 way to the centre to reduce deflection, rollers spaced every 60 degrees) ; 4) the difficult bit - some means of rotating it with the load of the bike (and possibly rider!) on top and braking it when not in use - suggestions more than welcome!

I was guessing at 3/4" ply for the top of the turntable (about 6 feet in diameter) with "gritty paint" (as used on boat decks) for grip, any improvements anyone can suggest?

[1] One of the bikes is known as Sir Nigel Gresley, after all.

-- Dave H. (The engineer formerly known as Homeless)

"Rules are for the obedience of fools, and the guidance of wise men" - Douglas Bader

A bloke at work asked if my bike was one of those that went "potato, potato, potato" - I told him no, it went "sweet potato, sweet potato, sweet potato - well, it's a Yam..."

[Andy Dingley]

On 15 May, 16:02, "Dave H." turntable

Why not a traverser, rather than a turntable? I presume the problem is largely one of access, not rotating them (you could do that by 3- pointing outside)

[meow2222]

On 15 May, 16:02, "Dave H." turntable up the end that we could roll the bikes onto to turn them around

Sounds a runner, though its a relatively complex option. Last time I did anything like this (for a very different app) I used 2 polythene sheets to give easy slip. That way you'd only need 2x 1/2" ply sheets and a central screw. No sinking it into the floor, and none of the other complications.

If you want to see what friction level that would give 2 binbags will survive a brief trial.

NT

[meow2222]

On 15 May, 16:02, "Dave H." turntable up the end that we could roll the bikes onto to turn them around

Sounds a runner, though its a relatively complex option. Last time I did anything like this (for a very different app) I used 2 polythene sheets to give easy slip. That way you'd only need 2x 1/2" ply sheets and a central screw. No sinking it into the floor, and none of the other complications.

If you want to see what friction level that would give 2 binbags will survive a brief trial.

NT

[Dave H.]

Eventually we could 3-point 'em, but the drive's full of cars to thread through even without nicking a bit for the garage, so we'd have to roll 'em backwards for 30 feet or so over gravel first... I like the traverser idea though, very Golden Age of Steam! We'll like as not have 5 or more bikes nosed into one side wall with a 4 or 5 foot gap along the middle for access, hence the idea of a turntable at the far end (it'll be a long one-and-a-half width (12 feet or so) garage so we can retain access to the garden alongside it).

Sort of like this...

----------------------------Wall------------------- =====workbench etc==============| t/t here |

-==)- -==)- -==)- -==)- -==)- |

---------------------------Wall--------------------| but with the bikes at an angle.

-- Dave H. (The engineer formerly known as Homeless)

"Rules are for the obedience of fools, and the guidance of wise men" - Douglas Bader

[MikeH]

SWMBO is an ex driving instructor, and in our garage we have two turntables[1] about a foot in diameter which she used to drive the front wheels of pupils cars on to. This then let them practise steering (feeding through the hands stuff) without straining the steering mechanism and without actually moving the car.

I reckon if you get one of those and put the bike on the centerstand on top of one, it should turn easily if you get both wheels off the ground.

I'll try it with the BM tonight and let you know - must be a sight cheaper then planting something 6 feet across into concrete.

[1] A pair of greased (probably) plates on top of each other.

[Dave H.]

Sounds a good idea, g/f has a bit of a job getting her GPZ11 onto the centrestand, though... have to send her to the gym, eh? Then she could carry me home when I'm drunk, too :o)

-- Dave H. (The engineer formerly known as Homeless)

"Rules are for the obedience of fools, and the guidance of wise men" - Douglas Bader

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember MikeH saying something like:

Which is all you need to do it. Someone has posted here about using a pair of greased beer trays for the same job, but for longevity, I'd use

14" steel plate wiv a centre bolt

[Dave H.]

I did consider using stout polythene as a bearing surface, but I suspect that any grit or similar that got in would increase the friction enough to make it unworkable, and it's likely to pick up quite a lot if it's *my* garage.... G/f needs to be able to spin her GPZ11 on it, too, and she's only ickle :o)

-- Dave H. (The engineer formerly known as Homeless)

"Rules are for the obedience of fools, and the guidance of wise men" - Douglas Bader

[Beav]

"Dave H." > > turntable

And it'd work well until the day something gets put in the garage "for a minute" and stays there 'til Nelson gets his eye back. You know that even wth the best intentions, that sort of crap happens. Then your turntable will just become "the floor".

[LSR]

I bought something called a "Bike Dog" years ago - it's like a flat rollerskate with heavy duty casters in each corner. You just roll the rear wheel onto it (the baseplate is about 5mm thick but very strong) and can then swing the back round. It easily copes with my '600. I use it on an old piece of lino as the garage floor is rough ridged concrete. I park it across the far end of our single garage and SWMBO can then get her car in too.

[Peter Ashby]

Dave H.

[Dave H.]

We'll definitely use good covers anyway (we've needed 'em, with no garage the bikes are in the back yard at the mo, so we can cover the bikes once they've dried off), but *metalworking* toolery, the shed up the garden has the saw bench, radial arm saw[1] etc. How does a multigym make that much dust???

[1] Allegedly the most dangerous power tool known to man :o)

-- Dave H. (The engineer formerly known as Homeless)

"Rules are for the obedience of fools, and the guidance of wise men" - Douglas Bader

[Dave H.]

Yeah, I know how that goes, but I do have Two Sheds too... and the garage should have a loft for storage (and Scalextric) to keep it vaguely under control. Of course, there'll be plenty of workbanch to get kippled, so that might divert the Depositors of Crap, hiding tools and small, vital, expensive or rare parts being infinitely preferable to covering concrete floors...

-- Dave H. (The engineer formerly known as Homeless)

"Rules are for the obedience of fools, and the guidance of wise men" - Douglas Bader

[Peter Ashby]

One of the wheel sets for things like tablesaws could perhaps be pressed into service in that mode. Might just take a piece of ply in the middle.

Peter

[Cicero]

================================== You could probably modify this idea to make a single giant skateboard:

[nightjar]

"Dave H." turntable up the end that we could roll the bikes onto to turn them around

Don't forget to allow for drainage, just in case the roof leaks one day.

Don't put the rollers in a groove. It will collect dirt and obstruct the rollers. Either cast in a raised track or fit a curved rail, which can be as simple as a strip of metal on edge. The latter will also accept V groove rollers, which will help keep the hole thing centralised and might do away with the need for a central bearing.

I would use chequer plate, either steel or aluminium. It will have a much longer life than ply. You can also bolt a vertical bar into it near the edge, to give you something to push it with.

Don't forget you will need access into the well for cleaning it out from time to time and for maintenance. A traditional bridge style railway turntable will allow that and use less material for the deck, although the pit does become something of a hazard unless you fit railing around it. A full disc top will need one or more access panels, arranged so that, by rotating the table, you can get to all of the pit. You will also need access panels near the wheels.

Locking is done with an L shaped bit of metal, arranged with the short part pointing down and fitting into a slot in the edge of the pit. The long bit is pivoted in the middle, with the pivot mounted on the edge of the turntable, near the push bar. Stand on the end and the short bit lifts out of the slot, allowing you to rotate the table.

Colin Bignell

[MikeH]

Tried it, but my centre stand is wider than the plates by an inch so no go.

I still reckon the idea is sound though.

[Dave H.]

Good idea, but it'd mean g/f having to get her bike onto the centrestand (even if only to get the dolly under the wheel), which is a hard-verging-on-impossible task for her (500lb bike, tiny lass) and it'd be difficult to get the bike balanced - ideally we want something that will support both wheels and the sidestand so one can ride or push it on, get off and spin it around before jumping back on and riding off into the sunset - so a turntable may be the best answer

-- Dave H. (The engineer formerly known as Homeless)

"Rules are for the obedience of fools, and the guidance of wise men" - Douglas Bader

[Thomas Prufer]

How about a six-foot plate, small pin in the middle, floating on a cushion of compressed air -- a large plate on an air bearing?

Turn off the air, and it'll be braked. Feather the edges of the plate, and no recess is needed in the concrete...

Thomas Prufer