External starters

[wbks]

Do many people in NZ have these? Wasn't really sure if it would go in the racing section, sportbike section, or bike gear section or what so mods if you think it would fit better somewhere else, put it there...
From what I've seen on TV it looks just like a small fourstroke engine in a solid frame, obviously torquey enough to turn a big bike over. I was actually thinking of making one of them, not really because I need one so much to start my bucket (although it could be handy on cold mornings that get me dripping in sweat before it even starts to turn over), but just for fun and maybe even pass it onto a racer for $100! It would most likely be a lawn mower engine I have lying around, put into a frame I'll make, with a cheap as I can find go cart wheel to turn the bike over, connected to the motor by a chain. So anyone know how the professionally built starters function? And never turned a lawnmower motor on its side, so anyone know if they can still run fine like so? Otherwise a cheap junker bike motor would suffice. What do you guys think of a project like this?

Your 2c wanted

[R6_kid:Me]

I've been thinking about fabricating one. You can either use a small four stroke motor... im intending to use an electrical starter motor from a 3.0L turbo diesel. I just dont have the $$$ at the moment to fabricate up the roller frame for it.

[wbks]

Think an electric motor would have guts to turn a bike over at the wheel?

[vifferman]

Think an electric motor would have guts to turn a bike over at the wheel?

If it can turn over a 3L diesel, it should be a piece of piss, geared right.
It's all about torques, innit?
A bike's starter motor is a lot smaller'n a car/truck starter motor, and it copes OK.

[wbks]

Yea I noticed how stupid that was as soon as I posted it lol. Could be better then a petrol motor i guess. Quieter, no issues starting or getting gas, just charging the battery for it. How much did you get it for, r6? reckon even a little one off a civic could do the trick? Also, what are you going to use for the roller? A go cart wheel would look and work the best from what I can think of

[vifferman]

Also, what are you going to use for the roller? A go cart wheel would look and work the best from what I can think of

Friction/traction is key - if you look at most of them, they use two tyred wheels a short distance apart, so you get more surface area against the back tyre of the bike.

[wbks]

Oh ok. So like two old bike tyres put together on a shaft with a sprocket on a chain running to the motor (electric or petrol). Is that how they work? Never really had a close look at them, they're not exactly featured next to the desmocedici lol

[vifferman]

Turns out you were right with your gokart tyre idea.
Linky.

[R6_kid:Me]

I'll be getting it for free when i go pick it up as my mate just 'wanted it out of his garage'

I was thinking of using a go cart wheel with possibly a minimoto chain/sprocket setup to re-gear it... might go up to pushbike chain if need be. Was going to to mount it on to a hand cart and use a car battery for power.

[wbks]

That looks like the plans I just roughly sketched out. I was just thinking it would be hard to make such a narrow profile while it still only holds the wheel from one side, it would probably flex heaps. Probably doesn't actually have too much stress on it though so it should work fine. Friction wouldn't be a problem if you make a little hook to hook it into the stand and hold against the wheel with heaps of pressure, and it looks like that one has what I'm talking about.... Or something... They all have petrol motors, though, which is weird if the electric motor is better. Any ideas why?
So they have a go cart wheel, but I thought go cart wheels don't run on an axle, and bolt on like a cars...

[wbks]

I'll be getting it for free when i go pick it up as my mate just 'wanted it out of his garage'

I was thinking of using a go cart wheel with possibly a minimoto chain/sprocket setup to re-gear it... might go up to pushbike chain if need be. Was going to to mount it on to a hand cart and use a car battery for power.

So are you going to weld a sprocket to the starter motor some how?