electric roller starter to start 250?

[cooperplace]

has anyone used one of these to start their 250? if so, do you have any advice re make of starter etc?
thanks

[Bevel bob]

At one time I did think about it for the first start of the day!, happily I have worked out a routine that works for me. Flood it till fuel drips well, lean on the KS till the compression eases then give if a full kick with the throttle held about a quarter open,Be prepared to blip the throttle to clear the excess fuel.If its an SSI be prepared to lean the bike over to the right side to speed up the tickover.

[ecurbruce]

You'll get the best advice from the race scene guys, as that's where the starters are most seen,,, but the most unique and most useful component that I liked is to use tapered boat trailer rollers, you know the ones that center the boat hull on the trailer, used in pairs like on a boat trailer, narrow part of the roller in the center. When starting your motor cycle, it keeps the rear wheel centered on the starter.
Honda automotive engine starters, with gear reduction, and the longer output shaft are useful.
I've been looking for a while, but have NOT built one, yet...

Bruce

[ElmrPhD]

Would love to sell you mine. Alas, I'm in Holland. It would easily start even a racing 250, but my 350 racer appears to have higher compression than the 10:1 that it's supposed to. So, even the big, super-expensive starters and the big, hefty Dutch guys who kindly try to push-start mine have difficulty.

It's a fair point about the v-shaped (boat trailer) rollers. Without them (like mine), you just have to learn how to keep the rear centered. No big deal.

I was literally and figuratively sweating bullets at Assen today as my bike is also difficult to keep alive until underway and we had massive delays at the first session. Had to re-start 3 times in the midst of a crowd of anxious racers... I've had to make several friends at the races to help start my bike. Still, it was an awesome time, blasting around a proper MotoGP track.

[DBDBrian]

As Bruce is contemplating manufacturing a set of V profile starting rollers, this is just a thought, the V profile rollers may not perform as might be expected.
I have not built a set of starting rollers as suggested, or indeed any, so I cannot speak from experience.
But in my experience as an engineer, anything running on the surface of a rotating tapered drum, is influenced up the taper not down.
A convex profile roller, (crown roller) would influence the wheel to the centre of the roller, where as a concave profile would influence the wheel out from the centre in either direction.
Before committing to full scale manufacture, a model mock up might be worth while.

Brian

[joe46ho]

http://www.motocicliveloci.it/italiano/ ... iatore.htm

[DBDBrian]

Well there it is Joe, I "certainly" can't argue with that one. Purely out of interest, It would be informative to see a set in action.
Brian

[joe46ho]

https://www.youtube.com/watch?v=M8e4iIt3aMM

not the greatest video, but this will give you an idea of what it takes to make your own...

[StewartD]

The video that joe46ho posted shows a rider starting and old Ariel (I think) on electric rollers. Note that he puts it in gear, (the click is quite audible), and pulls it back on compression before backing it onto the rollers. This is essential, otherwise the rollers will either stall or spin against a stalled rear wheel.

The extra steps of pulling back on compression, pulling in clutch lever and pulling the machine back a bit further, to make sure the clutch is free, will make a normal push start quite easy.

What it does is allow the motor to turn nearly one cycle (on a four stroke that is nearly two turns of the crankshaft), thus storing kinetic energy in the flywheels that will easily overcome the compression stroke.

Of course everyone used to start their 500cc single Manx Nortons and G50 Matchlesses at the start of racing in the 1960s like this. (Dead motor starts were the rule in Australia well into the 1980s.) These machines are a lot heavier than a 250 or 450 Ducati. Also in Australia, where road racing rules allowed the use of alcohol fuel, these machines ran very high compression ratios. These riders all knew the technique of pulling back on compression.

An electric roller starter is an unnecessary luxury.

Cheers,

Stewart D

[cooperplace]

it may well be an unnecessary luxury, but I want one.