Starter won't turn engine

MichaelB said:
Video #4 when pushing the kicker the rear wheel is spinning.
Is it in gear?
If so, Try neutral to relieve the extra load.
Click to expand...
I must have bumped the shifter when taking things in and out of the primary case. It's been in neutral every other time I've tested it with the same result. Thanks.
 
YellowPeril said:
Thanks for scolding me, I hope that makes you feel high and mighty.

I detailed these things in the videos, which I thought made it more clear.

The engine will spin with the plugs out, but not with one in it. You can see how fast it spins in one of the last videos, they're not long at all but forgive me for offending you by posting them rather than answering 'how fast does it spin'.

I have tried several batteries, all with the same result. These batteries work fine in my other bikes. I also have another 850 with no starter issues- I took the starter out of that one and tried it in the trouble bike. Same issue. I tried the old starter and the new gear reduction starter from the trouble bike in the 'good' 850- the old one turns it over fine, the gear reduction turns it over twice as fast.

I had everything hooked up through the solenoid and starter button, then decided to eliminate that for testing and have been using jumper cables to go direct from the battery to the starter with the positive grounded where the original negative wire was at the case stud next to the starter and the positive direct to the starter, touching the positive to a battery. The engine will turn about half a rotation and then stop. When the negative cable is touched to the battery it makes a big spark, so obviously something is stopping the motor from turning.

The engine is not wet sumped.
Click to expand...
It looks like you are missing the engine ground as I stated before. It belongs on the bolt near the base of the jugs. That is the only high amp connection to the battery.
 
YellowPeril said:
I have tried several batteries, all with the same result. These batteries work fine in my other bikes. I also have another 850 with no starter issues- I took the starter out of that one and tried it in the trouble bike. Same issue. I tried the old starter and the new gear reduction starter from the trouble bike in the 'good' 850- the old one turns it over fine, the gear reduction turns it over twice as fast.

I had everything hooked up through the solenoid and starter button, then decided to eliminate that for testing and have been using jumper cables to go direct from the battery to the starter with the positive grounded where the original negative wire was at the case stud next to the starter and the positive direct to the starter, touching the positive to a battery. The engine will turn about half a rotation and then stop. When the negative cable is touched to the battery it makes a big spark, so obviously something is stopping the motor from turning.
Click to expand...
I am still thinking that the wiring and solenoid are suspect.
 
L.A.B. said:
Have you got any thicker wires? If the wires are getting hot then they're not up to the job and the original starter wires were barely good enough so should be replaced. I can't see anything wrong with the assembly.
Click to expand...
I'm just using jumper cables right now, not the original wiring.
 
YellowPeril said:
I'm just using jumper cables right now, not the original wiring.
Click to expand...
Do you mean cables with an alligator clip on the ends? If so, I doubt that they will work, The teeth of the clips only provide point contact. Proper eyeletted leads bolted/screwed on to the terminals are necessary to carry the current. High resistance (due to bad contact) = heat.
 
oldschool said:
Do you mean cables with an alligator clip on the ends? If so, I doubt that they will work, The teeth of the clips only provide point contact. Proper eyeletted leads bolted/screwed on to the terminals are necessary to carry the current. High resistance (due to bad contact) = heat.
Click to expand...
I've tried a few different things....but the cables have worked on other bikes with no problem. I will try again with all the wiring hooked back up, but did that already with the same result. Thanks.
 
YellowPeril said:
I've tried a few different things....but the cables have worked on other bikes with no problem. I will try again with all the wiring hooked back up, but did that already with the same result. Thanks.
Click to expand...
There have been several references to starter cabling and the solenoid, but no confirmation about what you are using. Do you still have the original light gauge starter cables fitted? What about the solenoid? Is that an original? As has been pointed out, the original cabling is severely under-specified and should be replaced with heavier gauge wire. Similarly, the original solenoid is known to be a weak point.
 
Hi YP, I've kept out of the discussion related to cables, as I think you may have a mechanical issue. The fact your starter drive doesn't spin the crankshaft at the resistance of compression only is indicative.
Please dismantle your starter drive shaft and examine shafts and sprockets for signs of scoring and abnormal wear. There could be a misalignment in the drive. If the shaft bores don't align and/or are worn, the starter shaft could jam upon starter engagement.
Also, could the backfire device be at fault? I am shooting blindfolded - my experience with these parts is zero.

- Knut
 
Last edited:
For what its worth-

you have eliminated batterry and starter. Repeating the same tests over and over won't change that.

So that leaves you two options, elec or mechanical.

Since it kicks over and runs as it should- mechanical can be eliminated.

That leaves the starting system only - either wiring, or a component (not the starter you eliminated that.). You have known good replacements for components- switch out 1 at a time. And goes without saying, but of course I'll say it- recheck all connections, test all wires.
 
Looking at the videos. You are missing the Red ground lead that connects the battery to the engine case. No amount of 'testing' using jumper leads and crocodile clips will deliver the amperage to drive the starter motor properly. The result is what you are seeing, poor starter performance and clips cables getting hot. You said you tried your starter on another bike, have a look at that bikes wiring and copy it!
Assemble the wiring, solenoid and starter as per the manual and as long as you have a good battery (tested on the other bike?) it should work. I will take a good bet that your original starter will work as well. All your trials and tribulations are just highlighting that using jumper cables and croc clips wont deliver the required amps, and you have spent money on another starter motor that really wasn't needed...
 
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You stated the positive cable and also your jumper cable, were on the engine casing stud. Is that stud corroded? Has someone used a thread locking product on the stud threads into the casing hole? Excess resistance there could explain all your test results.

BTW: Calling someone high and mighty for trying to help you out seems counter productive for someone asking for help...
 
mdt-son said:
Hi YP, I've kept out of the discussion related to cables, as I think you may have a mechanical issue. The fact your starter drive doesn't spin the crankshaft at the resistance of compression only is indicative.
Please dismantle your starter drive shaft and examine shafts and sprockets for signs of scoring and abnormal wear. There could be a misalignment in the drive. If the shaft bores don't align and/or are worn, the starter shaft could jam upon starter engagement.
Also, could the backfire device be at fault? I am shooting blindfolded - my experience with these parts is zero.

- Knut
Click to expand...
Thanks! That's a very thoughtful response, I also believe it has to do with the compression. I took the head off today and am thinking the previous owner skimmed it to bump the compression up. Add to that the large amount of carbon on the pistons...extra high compression. I needed to check for cracks and porosity anyway, and will measure to see how much has been taken off. I'll probably try a spacer plate between the head and barrel when I put it back together.
 
YellowPeril said:
Thanks! That's a very thoughtful response, I also believe it has to do with the compression. I took the head off today and am thinking the previous owner skimmed it to bump the compression up. Add to that the large amount of carbon on the pistons...extra high compression. I needed to check for cracks and porosity anyway, and will measure to see how much has been taken off. I'll probably try a spacer plate between the head and barrel when I put it back together.
Click to expand...
Did you do a compression test before stripping the top end?
Did you mean you were going to fit a spacer between the 'barrel and crankcase ' ?
Do you have a photo of the skimmed surface and the excessive carbon build up?
 

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