Shop built roller starter

Monkeypants

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Dan Smith built this roller starter for his Velo Roarer project. That bike has been sold to the Solvang Museum in California. The buyer did not need the starter so Dan kindly gave it to me.
It is bolted to the floor and starts the 10.8 to 1 1360 easily, provided a big battery is hooked up. The car battery was enough for the 9 to one Rapide, but wouldn't start the 1360. For that I borrow a battery from the F350 diesel or a similar big battery from a JD crawler.
Then the bike fires instantly. Four plugs and an extra hot twin driver Pazon ignition help.
This is not an easy bike to kick over.

 

Bill Thomas

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Sounds Nice Glen, I like the 2 into one Exhaust, Bit like my home made one, I did for my Special.
I am sure it was worth a few BHP, Better than L/ning Pipes.
Cheers Bill.
 

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vibrac

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I drive mine with a mains motor 4.5 hp it draws 13.5 amps mostly I get by without the electric supply tripping
The frame and rollers was from a guy on eBay who sold them for £350
 

Magnetoman

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For what it's worth, I haven't started a Vincent on them but my DocZ rollers with two Ford starter motors draws a measured 480 A so ~7.7 h.p. If it takes a while to start the power would drop by 15% (to 6.6 h.p.) after 15 sec. and by 30% (to 5.4 h.p.) after 30 sec. This when using a marine MCA845 deep discharge battery. What may be more relevant is a significant amount of power was lost in the original cables and clamps so I upgraded both.
DocZ_connector.jpg

I bought welding clamps as replacements and modified them with ~1 sq.in. Cu pads to make contact with the Cu electrodes I made to bolt to the battery. The resistance of those connectors is now only 0.22 mΩ each. Although with 500 A through them the voltage drop at each clamp is now only ~0.1 V that's still 55 W of heat each. Each of the 2 AWG cables that came on the rollers had 6x that much loss (1.36 mΩ), which I reduced to 0.86 mΩ by replacing them with 1/0 AWG. Still the losses in both of the connectors and cables account for ~10% of the total power supplied by the battery. Such is the nature of high currents. However, before these upgrades to the circuit the losses were over 2x as much so only ~80% of the available power got to the motors, with the rest helping to melt the polar icecaps.
 

Dave61

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I`ve bought a frame & rollers of eBay,if anyone has seen my attempt at starting our Rapide for the first time this won`t seem unreasonable :)
I`m intending to use a mains motor, probably a 1.5KW / 2HP 1400RPM one.
Will this be man enough for starting a twin or should I go for a bigger rating ?
Frame & rollers look pretty good & were £263.75 delivered so not too steep.
Cheers
Dave

PS. I`ll trail a long extension lead for when I inevitably stall it.
 

Bill Thomas

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I know you have a health problem Dave, why didn't you go for a French electric starter?
Good Luck, Bill.
 
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Dave61

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I know you have a health problem Dave, why didn't you go for a French electric starter?
Good Luck, Bill.

If I can get away without fitting an electric starter I`d prefer it but reality may change my mind, it`s the thought of breaking the sprag clutch that puts me off.
Saw this thread & thought it may be a good idea like Tim said, ride a circular route back to home, & it`s not going to cost a lot.
Once I`ve got some miles on the bike & it`s loosened up a bit hopefully I`ll have cracked the starting technique.
Also liked the idea of being able to get the oil circulating using the rollers.
Getting ahead of myself as I`m waiting on Simon doing the dating letter so I can get the reregistration completed.
Cheers
Dave
 

BigEd

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If I can get away without fitting an electric starter I`d prefer it but reality may change my mind, it`s the thought of breaking the sprag clutch that puts me off.
Saw this thread & thought it may be a good idea like Tim said, ride a circular route back to home, & it`s not going to cost a lot.
Once I`ve got some miles on the bike & it`s loosened up a bit hopefully I`ll have cracked the starting technique.
Also liked the idea of being able to get the oil circulating using the rollers.
Getting ahead of myself as I`m waiting on Simon doing the dating letter so I can get the reregistration completed.
Cheers
Dave
Only my opinion, as I don't know you or your circumstances but I think you would have been better putting your money towards an electric start kit. My Rapide has always been a good starter, if it needed more than two kicks you had forgotten to turn the petrol on or similar. I am pretty active but 50 + years of kickstarting bikes my knees have had enough. I have several more modern electric start bikes so I know how convenient a handlebar starter button is. I have fitted my Grosset electric start a few years ago and it works very well. I have even taken the kick start lever off so I'm not even tempted to kick it. If for some reason the battery is flat it will start with a push as I don't have coil ignition. Tales of broken sprag clutches etc are, I believe over-exaggerated with most problems being caused by incorrect fitting and lack of attention to ignition timing. Francois stresses in his instruction sheets the importance of not having too much advance for starting as it is backfires that are not good for sprag clutches.
The above sounds like an advert for electric starts but if riding becomes more difficult we have to try to make things easier to ride and that, first and foremost is our ability to get the thing going.
A set of starter rollers would be great in your workshop but is no use at all when you are not at home. If I want to spin the engine over at home I use the electric start. As I said at the beginning, just my opinion but based on using an electric start on my Rapide.
 
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Bill Thomas

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A good Twin should start after one or 2 kicks, Mine are OK from Hot or Cold, It's warmish that drives me mad.
But I have now found they need choke or flooding, If not run for 1/4 of an hour , By the coast.
Cheers Bill.
 

Dave61

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Only my opinion, as I don't know you or your circumstances but I think you would have been putting your money towards an electric start kit. My Rapide has always been a good starter, if it needed more than two kicks you had forgotten to turn the petrol on or similar. I am pretty active but 50 + years of kickstarting bikes my knees have had enough. I have several more modern electric start bikes so I know how convenient a handlebar starter button is. I have fitted my Grosset electric start a few years ago and it works very well. I have even taken the kick start lever off so I'm not even tempted to kick it. If for some reason the battery is flat it will start with a push as I don't have coil ignition. Tales of broken sprag clutches etc are, I believe over-exaggerated with most problems being caused by incorrect fitting and lack of attention to ignition timing. Francois stresses in his instruction sheets the importance of not having too much advance for starting as it is backfires that are not good for sprag clutches.
The above sounds like an advert for electric starts but if riding becomes more difficult we have to try to make things easier to ride and that, first and foremost is our ability to get the thing going.
A set of starter rollers would be great in your workshop but is no use at all when you are not at home. If I want to spin the engine over at home I use the electric start. As I said at the beginning, just my opinion but based on using an electric start on my Rapide.

I`ve always found your opinions pretty sound Ed.
As I haven`t actually had the chance to see how I get on with with the Vin, I`ll have to make decisions when I`ve had a decent go.
I`m not seeing the rollers as a Panacea for any concerns I may have, just like a gadget & can`t help myself sometimes.
I`ve got Grosset ignition & Mikuni carbs so think it should be a good starter.
Cheers
Dave
 
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