Was looking over the HD shop manual, and saw the starter motor specs. An 883 starter has 300 amp (max) stall current @ 2.5V. and 5 ft-lbs stall torque @ 2.5V.

The 1200 starter has 400 amp stall current and 8.7 ft-lbs stall torque.

So did anyone ever experience poor starting torque after a 10:1 1200 conversion?

have never heard of a starter motor prob on a sporty.......other normal wear and tear

Hey Engine,

My starter gets the job done on my T-storm conversion but just barely. Its sounds like the starter doesn't have enough to turn it over on the first try, kind of like a near dead battery. I usually let off of it quickly and it works just find the second time around. So far, it hasn't been a major concern as I have not had any failures. But, the thought of getting a higher torque starter has crossed my mind.

I sometimes have to hit the button a second time since my conversion. The first time, it kinda hangs.

Looks like I have to order new battery at least! The old one is in fatal condition...
Ride safe!

Lukas
883 '97 - almost converted to 1200
see my bike at http://moto.e-technologie.net/harleyopis.html

I have been asking the Dealer and my Indy if there is any difference in the 1200 and 883 starters and they all say that they are the same. I am glad the you were able to find a spec. list. I will be calling a electrical motor repair shop and see if they can re-wind my starter to produce more twisting force cheaper than buying a 1200 starter.

no receipts for a different starter amongst my paperwork, I bought a new gel filled battery 18 months ago and apart from the first turn sounding tired it usually starts second turn.
mind you I do have it hooked up to an optimate to keep the battery charged up as I dont get to ride very often.

On the four speed Sportys, the ring gear sometimes comes loose and spins free on the clutch hub. I had mine tig welded in a few spots to keep it on. Makes you think the starter drive is slipping when it happens. I strongly recomend that four speed owners have the ring gear welded when the clutch hub is out next time. Cheap insurance.
Ted

My bike starts perfect with 10.75 compression and the stock starter.

Your cam makes a huge difference in the amount of force required to crank the engine. A low overlap cam like the stock cam, n2.. .etc will make the bike much harder to crank than a large overlap cam such as the andrews n6. The downside of high overlap cams is the anemic performance at low RPMs. The plus on high overlap cams is your effective compression ratio is proportional to your RPMs. I.E. at idle it will bleed a static 10.5:1 compression ratio so it "behaves" like an 8:1. However at 6000 RPMs it makes your engine have an effective compression ratio that "appears" higher than your static compression ratio. Example: the n6 in my bike at cranking RPMs bleeds my cylinder pressure to 125 PSI. This is due to the fact my intake valve stays open well past the time the piston passes bottom dead center BDC on the compression stroke. At higher RPMs the fuel/air mixture racing past the intake valve has enough inertia that it continues to fill the cylinder even though it is part way into the compression stroke. This yeilds a higher peak cylinder pressure when the piston is top dead center TDC than if the intake valve had closed at BDC. I realize most harley owners are more interested in the chug, rather than a scream. A n6 is not the right choice for many sportster owners. I kinda like the sound of a sporty engine roaring off the line taching 4000 to 6500; call me wierd. Addertooth

I thought that Overlap was the effect of exhaust rushing out of the cylinder pulling in the new charge through the open intake valve and Intake close degree at ABDC was the measure of when the motor starts its compression or a measure of how much stroke is used in compression thus raising the cranking pressure. Please set me straight if I am out in left field as I am trying to learn this stuff.

Hey Engine,

My starter gets the job done on my T-storm conversion but just barely. Its sounds like the starter doesn't have enough to turn it over on the first try, kind of like a near dead battery. I usually let off of it quickly and it works just find the second time around. So far, it hasn't been a major concern as I have not had any failures. But, the thought of getting a higher torque starter has crossed my mind.

Same here.

Installed N4 cams after the conversion and experienced a not-so-easy start with gronk modded mufflers (turned over fine but wouldn't "light."

Went back to the CS slip-ons; now, when I hit the starter - - BAM! it's goin'!

Regards,

Mikel NY,

You are right on the mark. I used the term overlap to initially describe a condition of closing the intake valve later into the compression stroke. It was a gross oversimplification. Most (but not all) high overlap cams also perform late closing on the intake valve during the compression stroke. And it is the late closing that acts as a pressure release at cranking rpms. And give a net increase in cylinder pressure at TDC at higher rpms versus a cam that closes the intake valve at BDC.

Addertooth

Thank you. This stuff is hard to learn and retain. I have been trying to figure the cam spec.'s out for about a month now and feel I have only scratched the surface. When I think that I have it all sorted out, The knowledge base chimes in with: Why does everybody think cams are the primary factor in where your torque peaks? It is your exhaust that really determines where your torque peak is at.

Put a Supertrapp 2 into 1 on it and you can move the power around just by the addition or subtraction of discs. I thought Intake Close Event was more important, but have been corrected. But back to the issue at hand. My starting problems, I believe, are from my intake closing at 41deg ABDC. A very early closing.

Mikel NY,

Yes, all of the above. An engine is the sum of it's parts. Your hp/torque curve can be shifted around by changing ANY of the major components. Exhaust can affect your curve markedly, so can a cam. Smart money is spent when ALL of your components are selected to put the power curve where you want it. Many builds I see are utilizing non-complimentory components. I see people who say they are after grunt, but throw in low velocity components which are detrimental to low rpm performance.
Pick where you want to produce your power, then select a collection of components that ALL work together to achieve that goal. In the end you will be happier with your results. Addertooth

Since my conversion, I have noticed the same issue here.

I have been asking the Dealer and my Indy if there is any difference in the 1200 and 883 starters and they all say that they are the same. I am glad the you were able to find a spec. list. I will be calling a electrical motor repair shop and see if they can re-wind my starter to produce more twisting force cheaper than buying a 1200 starter.
In your case the dealer is probably right. I think they quit using the smaller starter for the 883 after 1994. My 94 still has the smaller starter and handles my conversion with no problems. (KB 9:1 pistons, everything else is stock).

I have found that most of my starting issues are caused from the ignition. I hooked the laptop to my Thunderheart ignition and found that from 0 RPM's to 1000 RPM's it was set at 10 degrees BTDC!! I changed the 0 and 250 RPM's to 0 degrees and it starts MUCH better. The spark does not hammer the starter backwards but instead waits for the crank to roll over TDC then fires.

After conversion to 1212 with 10.5:1 compression my starter has to build up the grunt to kick the engine over. Usually it clicks, the mileage readout goes dead and then it finally starts turning over the engine. Regardless if the starter motors are the same for 883's and 1200's or whatever, I need a starter with more torque or something.

I sometimes have to hit the button a second time since my conversion. The first time, it kinda hangs.

MIne does the same thing but I just keep the button pressed when it pauses.

After conversion to 1212 with 10.5:1 compression my starter has to build up the grunt to kick the engine over. Usually it clicks, the mileage readout goes dead and then it finally starts turning over the engine. Regardless if the starter motors are the same for 883's and 1200's or whatever, I need a starter with more torque or something.

I would do a load test on your battery to rule out a weakening state of charge....

I took another members advice and went with a AllBalls 1.4Kw starter and compression releases. I may not have really needed it, but for my own piece of mind and while it was apart. What to heck, it wasn't that much money.
Definitely keep a fully charged battery.

I could notice a definite difference after my 1200 conversion. But it seems to be lees a starter problem than a battery one. I ditched the stock HD battery and got a 'Wild Boar', and the starter lag, or whatever you want to call it went bye bye.

Hmmm.... a stronger battery. Something to think about. Maybe a battery with the same voltage, just higher amps.

I am having starter problems that have been discussed here on a pretty regular basis. Here is the story..
1988 Sportster. 883-1200 conversion done by Johnson Engine Technology. It is a 10.5 to 1 compression motor and puts out an estimated 88-91hp.
Bike has 3000 miles on it since the engine conversion that was done in 2001.
I run Mobil 1 V-Twin full synth in the engine and the primary and I ALWAYS have the battery on a tender. The bike is stored in an unheated detached garage.

The starter that is in it is the stock 883 starter from 1988. I believe it is a 1.2KW starter.

Since I got the bike I have had problems with the starter turning the engine over. I replaced all the cables and the battery. Stator and charging system are all good. What happens is this... I press the starter button and usually nothing happens for a second or 2. Then... the engine just starts. Sometimes if I catch the motor on the correct compression stroke the bike starts just like any other normal bike. If I remove a spark plug the starter turns over the motor perfect. When the bike is cold.. its around 40 degrees around here now... the bike is a real bear to start. Yesterday it started its usual way (click...silence...start) and I went for a little 20 minute ride. I stopped to get gas and the starter would not turn the motor over. I kept my finger on the starter button and I got a nice puff of smoke that came from under the starter (between the starter and the engine case). It smelled like a motor that was burning up. It wasn't a burnt wire insulation smell. I put it in 2nd gear and we tried to bump start it but the compression is too high to start it that way unless I am on a hill. After a few failed attempts I hit the starter button and after 2 seconds of silence the bike started right up. After that... I stopped the bike several times throughout the day and it started up every time the same way.... hit the start button... click.. silence.. and suddenly the engine starts. I VERY rarely ever actually hear the starter turning.
My thoughts are that the stock 883 1.2KW starter (they had this smaller starter for the 883 prior to 1994 I believe) doesn't have enough balls to turn this motor over. The part that boggles my mind though is why it has a tougher time starting the motor when it is cold.
I would really appreciate some help on this. I am thinking I should buy a new 1.4KW high torque starter for it. Suggestions??

Was looking over the HD shop manual, and saw the starter motor specs. An 883 starter has 300 amp (max) stall current @ 2.5V. and 5 ft-lbs stall torque @ 2.5V.

The 1200 starter has 400 amp stall current and 8.7 ft-lbs stall torque.

So did anyone ever experience poor starting torque after a 10:1 1200 conversion?

10.5 compression, 551s, cranking pressure 190-195 and it cranks well for starting.

<The part that boggles my mind though is why it has a tougher time starting the motor when it is cold.>
Um... the oil is thicker when it's cold, all things being equal. It takes more torque to spin the motor.

jgcable.
You might want to check the cable connection on the starter. The puff of smoke tells me loose connection.
I'm running the original 87 883 starter on my bike with no problem. I'm well over 200# cranking pressure. I posted earlier in this thread about the ring gear spinning on the 4 speeds. That's always worth taking care of if the clutch is removed.
Ted

jgcable.
You might want to check the cable connection on the starter. The puff of smoke tells me loose connection.
I'm running the original 87 883 starter on my bike with no problem. I'm well over 200# cranking pressure. I posted earlier in this thread about the ring gear spinning on the 4 speeds. That's always worth taking care of if the clutch is removed.
Ted


Thanks for the response. The first thing I checked was the cables. They are all brand new super heavy duty with gold contacts and they are all tight. The puff of smoke came from inbetween the starter casing and the engine casing.
I am going to check it again though. Thanks.

<The part that boggles my mind though is why it has a tougher time starting the motor when it is cold.>
Um... the oil is thicker when it's cold, all things being equal. It takes more torque to spin the motor.

But I am running full synth oil. It doesn't appear to be much thicker at all in the cold weather but I guess it gets a little thicker.

I'm over 12-1 compression, 240psi cranking pressure, 88 inch. Stock starter works just fine. I use a "Big Crank" battery. Best battery I have found for the price ($69). Use quality battery cables like those made by Taylor.

http://www.batterymart.com/p-Big-Crank-ETX20L-Battery.html

I have had a klick,pause,start issue as well,even after I bought a brand new Hawker battery.
When I raised the engines compression,its displacement to 1250cc and switched to 536 cams, it became annoying.

Then I decided to change battery cables and to overhaul the starter contacts.
Now I´m using Yooper cables
http://www.harleyhog.co.uk/yooperbattery/cables.htm

For the starter,I changed contacts with bolts and nuts,also the solenoid plunger.
All looked badly corroded.

Now my bike runs on the very first push of the starter button.

I think,because they add a lot of undesirable resistance,
old cables and corroded contacts are responsible for a vigorous voltage drop within the electrical starter´s system.

Ralph

jgcable the smoke came from between the starter and the motor.It sounds like a ground problem. The cable only provides half of the current path. On a starter the circuit is completed through the mounting surface. If it is not clean and tight you will drop voltage. You might try running a ground cable from the starter to the battery, at least to test it.