ET: Engine (Twin) Twin e-starter options?

stu spalding

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The fear factor of using the stock valve lifter on a twin with an electric start is minimal in reality verses the strain on the starter.
It also helps if a lithium iron battery is being used as these batteries need "waking up" a bit before applying full load. Switching the headlight on is the usual ploy but if an LED headlight is fitted spinning the motor over with no compression does the job. Cheers, Stu.
 

Dave61

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A friend in my section has a Shadow on 8.5:1 pistons c/w Grosset starter and uses the HD style automatic decompressors all the time, and has had no problems to date,

I'm fitting my Grosset starter & like the idea of these Automatic Decompressors, but wondered about only using the ignition to stop the engine running or do you leave the existing set up in place.
Vibrac did post about backfiring when just turning the ignition on & I'm sure someone mentioned the engine can spin backwards if you just turn it off on the switch.
Don't want to break it prematurely, believe me, if it can go wrong expensively when I'm doing it it will ! :)
Cheers
Dave
 

Oldhaven

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Here is a picture of the solenoid installed and of the small hole in the combustion chamber. I suppose it would be possible to “tune” the starting compression for easier starting by fitting a metering jet in this small hole. The location does make removal of the UFM and head brackets necessary for servicing or cleaning the device and I will have to machine a clearance recess in my aluminum head bracket, since it has a flat bottom. Looking again at the pictures I can see that Greg’s advice about a banjo fitting would be possible. I believe the HD’s run this off the starter circuit and vent the gases internally into the exhaust.

 
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greg brillus

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On the 600 Comet I did a year or so back I just used a small horn type button on the bars to operate the solenoid whilst turning the engine just over TDC.........With the AMC type Norton box you needed to turn the engine more than past TDC for a one kick start. No big effort needed and start readily with a good carb and ignition. The 600's go really well when set up correctly, they make for a fun ride.
 

Comet Rider

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I'm fitting my Grosset starter & like the idea of these Automatic Decompressors, but wondered about only using the ignition to stop the engine running or do you leave the existing set up in place.
Vibrac did post about backfiring when just turning the ignition on & I'm sure someone mentioned the engine can spin backwards if you just turn it off on the switch.
Don't want to break it prematurely, believe me, if it can go wrong expensively when I'm doing it it will ! :)
Cheers
Dave
Hi Dave,
He has a BT-H on his bike, so uses the ignition kill button.
The beauty of the automatic de-compressors is that you push the button down, and when the bike fires the pop closed. It's much easier to buy the 10mm ones, as they are used by both HD and many chainsaw makers. The 14mm ones are very expensive,.

Neil
 

Little Honda

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After re-reading all of this Ive decided, for now, to continue overeating and doing lots of leg curls on the home gym.

Glen
I did several 100 miles testriding of Ernst Hegeler´s home made Norvin with his own home made engine. He
does not make bigger engines, than 1000cc. You can find his starter system pictures within this subject. The
problem of his solution is the price. Interested ones do not value, that his starter is in the place of the original
dynamo, so causing the purchase of his dynamo/ignition solution as well. His dynamo delivers safe 150W in
place of the original magneto, being gear driven and having an electronic ignition in place of the original
ATD by 2 wearfree pick-ups, feeding a black box for both single or double ignition.
Starting goes easy by pulling the decompression lever, when pressing the starter button, keeping the lever
pulled app. 2 seconds, until the engine winds at a continuous sound, then releasing the valve lifter and continue starting. The engine starts immediatly after closing the valve lifter with the throttle untouched all the time.
The system operates dead reliably, the engine starts every time like any car engine. The starter motor used
is a Volkswagen manufactured starter which can be bought world-wide at low prices from any Volkswagen
dealer. The only problem is, you have to order according to Volkswagen business terms, ie. delivering an
identity number of the car, the order is related to.
Regarding the fact, that the Hegeler solution is a complete unit for starter, ignition and dynamo, it is not
expensive at all. It is simply the best in reliability, but not separable into its single parts: ignition, starting and
generating Voltage, it´s a unit.
 

BigEd

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I'm fitting my Grosset starter & like the idea of these Automatic Decompressors, but wondered about only using the ignition to stop the engine running or do you leave the existing set up in place.
Vibrac did post about backfiring when just turning the ignition on & I'm sure someone mentioned the engine can spin backwards if you just turn it off on the switch.
Don't want to break it prematurely, believe me, if it can go wrong expensively when I'm doing it it will ! :)
Cheers
Dave
My own experience of fitting, using and thoughts about the Grosset electric start on a Rapide:-
  1. It is not a big deal for an average home mechanic to fit the Grosset starter. Most of it is disassembly and reassembly with new parts in the kit. The only modification that needs some machining is the part of the kickstart ratchet mechanism. There are pictures of two suggested way of doing this in the instructions. The kick start quadrant needs thining a little and this can be done with an angle grinder or a bench grinder. The gear cover modifications can be done with a hacksaw and file to make the cutout for the narrow transfer gearbox and a sander to relieve the inside of the gear cover to create a bit of extra clearance. The battery platform may need a mod to accommodate whatever battery you decide to use. The starter solenoid fits nicely out of the way under the battery platform.
  2. My engine as I have already mentioned elsewhere has 8:1 pistons and Mk 1 cams. The battery is a Lithium Shorai. The starter turns my engine over without using the valve lifter. If for whatever reason the battery was getting low I see no reason not to use the valve lifter to get the engine spinning first before dropping the lifter lever. Before I fitted the electric start I always held the valve lifter in and released it near the bottom of the swing so the spinning flywheel momentum did the work of getting over the compression. It almost always started first or second kick. I can never understand why people spend time listening to the inlet suck to find the long gap between compressions position and then ease it over compression, at least not on a fairly standard motor. (That might provoke a little feedback in this thread.)
  3. Regarding the reluctance of some people to use the original valve lifter equipment due to perceived fragility. Mine has been OK, not fallen to pieces or lost one of the little needle rollers and it has done tens of thousands of miles in my hands. How many people actually have personal experience of the standard valve lifter mechanism failing if it has been assembled correctly? (Do we need a poll?)
  4. Stopping the engine. The sprag clutch doesn't like attempts to make it go backwards as happens if the crankshaft turns backwards. (François stresses the importance of correct ignition timing so there is no chance of a backfire. I use a modern BT-H magneto, auto advance and never once had a backfire when starting. Maybe people with manual magnetos might be most likely to have this problem if they don't have the adv/retard lever in the right place?) If you use the valve lifter to stop the engine then there should be no chance of the crankshaft going backwards as there is no compression that a piston might bounce back from and as there is no compression there should not be any chance of a backfire. If you use a kill button there should be no spark so no chance of a backfire. There is still some compression so there is a chance that a piston coming up to TDC on the compression stroke could bounce backwards. I don't know how much force this would have or how much strain it would put the sprag clutch under. My guess is probably similar or less than the strain experienced when the engine is started without using a valve lifter.
Well, that may have given you something to think about or at least some targets so you can shoot me down in flames.:cool:
P.S. My right knee likes the electric start and I have (bravely\foolishly?) removed the kickstart.
 

greg brillus

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All good stuff Eddie.......Yes i have found little in the way of issues with the Grosset starter with stock or near stock engines........It is the larger capacity, or more highly modified engines where the trouble starts.........I think a few on here mentioned about the TP squish band heads causing possible grief as the compression characteristics seem to be more adverse than the stock Hemi heads.........I started up this 600 Norvin I built a couple of years back today, and it definitely has some serious punch to the exhaust note........ From memory it runs a Mk 2 cam and 36 mm Mikuni carb, but everything else is quite normal.........(Normal......that's not a Vincent word is it........???.......)......... ;).
 
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