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Slow crank but turns over

PattiB

Patti B
My 2000 R1100R has always had a slow crank in warm weather or cold. New battery, didn't make a difference. It just doesn't seem right that a big engine would have a starter that just barely cranked enough to turn over the engine.

Here's what I was going to check: Ground connections, starter button contacts and connections on the starter.

Any other things I should consider? Oh and the alternator belt was replaced at about 44k it now has 55k on it so I don't think that's the issue.

Or is it just time to get the starter rebuilt or a new one? My mechanic didn't seem to think it's a problem...but he's not going to be the one stuck out somewhere with a non starting bike.
 
It may be one's personal definition of "slow" cranking...
It would be best to compare it side by side with another bike or two.
None of my oilheads (on my 3rd now) would be slow unless the battery was really dying.

Many "mechanics" are actually only factory-trained parts replacers - they are not interested in , or knowledgeable in, genuine troubleshooting. May be time to seek a new one.

You're on the right track; also check the battery connections themselves. Minutely examine the heavy cable from the battery to the starter, and the heavy ground cable, battery to frame. One may be deteriorating inside and you can't see it. If you see any corrosion or discoloration anywhere along these cables, replace it.

I'd doubt the starter button itself is part of the root cause, as that only energizes the starter relay (on top of the starter motor) - another possible culprit.

This is probably irrelevant, but may be worth consideration: I've seen on engines that had points instead of electronic ignition, that bad ignition timing would slow down the cranking. I don't know if a timing issue (whether at the Hall trigger or within the computer) would have this effect on our oilheads.
 
It sounds pretty normal to me. It's tough to get those big 'ol pistons moving. It's not gonna sound like your inline four or your car. If the mechanic said OK I'd probably assume it's good-to-go. Do you have someone nearby with another oilhead you can compare it to?

Lot's of folks (myself included) carry a set of motorcycle jumper cables. You'll probably never need them, but it may give you some peace of mind.

Here's something else. A weak battery, poor connections, or a starter using too much energy will cause the ABS to fault on startup. If your ABS is working fine you are definitely OK.
 
An article about starter lube in MOA

A few months back I seem to remember an article by Paul G. or Mathew P. on the oil head starter removal and lubricating maintenance. I would have to look through my stack but by memory you would disconnect your negative battery cable, remove the starter, clean the shaft and through out mechanism and then put a conservative amount of lube on the respective shaft and mechanism. Might want to check with either one of those guys to get specifics.
 
A few months back I seem to remember an article by Paul G. or Mathew P. on the oil head starter removal and lubricating maintenance. I would have to look through my stack but by memory you would disconnect your negative battery cable, remove the starter, clean the shaft and through out mechanism and then put a conservative amount of lube on the respective shaft and mechanism. Might want to check with either one of those guys to get specifics.

+1 . Carb cleaner works well then lube it
 
My 99 R1100r is slow cranking as well, about 3 seconds on the starter each time. Occassionaly it starts in 1 second if it sat for a few days on the charger. So I thought it might be the battery but the person I bought it from said it was more likely the Power Commander remapping of the fuel injection. So I've been dealing with it for a year now and am going out to buy the connections for the power commander so I can readjust it. I'd rather have it start right up than have torque and HP at different rpm's than was standard.
 
Slow cranking, aside from a dirty starter, is also an indication the magnets have come loose from inside the starter can, like they did on my 94 RS.

When that happens, the starter is able to crank yet, but the magnets are now grinding on the starter rotor whenever starting the bike. On my RS I dissassembled the starter, cleaned out the magnet shavings and grime, cleaned and scuffed out the magnet housing, and re-epoxied the magnets to the housing.

I had also bought a salvaged Valeo starter for a Renault car (same starter as in the early Oilheads) and I used parts and magnets from that starter with my original starter. Been cranking fine now for almost five seasons.
 
Oilheads are big twins. It is normal for the starter to turn these engines rather slowly. Short of changing the flywheel/starter gear ratio or finding a way to use a different/more powerful starter there is not much that can be done.

The trick is to recognise the difference between "normal slow" and "abnormal slow".
 
Here's something else. A weak battery, poor connections, or a starter using too much energy will cause the ABS to fault on startup. If your ABS is working fine you are definitely OK.

Thanks Jim. Yes ABS does engage only had it not engage after a long layover once. I know how that is or maybe if it stalls and I have to restart sometimes the ABS will not engage.

I don't think I need a new mechanic...this guy has been in business for 20 yrs so I think he knows what he's doing. It is a small independent shop and I get great service and attention from him. Hard to find these days.
 
Followup?

So what became of the starter motor turning slow? I have the same issue on my 1988 R100RS airhead....would love to hear about how you ended up resolving the issue as I'd like to start troubleshooting.
 
In another post someone suggested releasing the starter button after the engine has turned over 3 times, then hit the button again. This works on my 95 R1100R when cold. When warm it starts on the first touch of the button.
regards,
Mark
 
Check the battery to ground cable by putting a battery jumper cable on the battery post and the other to a good ground on the engine. Hit the starter. That's the usual culprit on seasoned bikes.

If it didn't work, whilts you got the bike apart run the jumper from the other battery terminal to the starter, hit the starter button.

If that didn't work before you dig further into the bike you might want to check the terminals again or install a known good battery and try it.

Now your down to the load shedding relay or the starter. The starter is more probable to be the cause so with a good starter that you heard start a bike, exchange the starters.
 
In another post someone suggested releasing the starter button after the engine has turned over 3 times, then hit the button again. This works on my 95 R1100R when cold. When warm it starts on the first touch of the button.
regards,
Mark

You can actually count when it has turned over three times ?
 
How's the temperature in Cleveland nowadays?
Colder temps = thicker oil and less battery cranking capacity which in turn = slower cranking. ?
 
Slow starter cranking on an Oilhead is common and caused by many factors:
1. Battery condition of course, these bikes will start on lower than 12 volts, but they will crank slow and get slower quickly. Cold temps make it worse.
2. Yup, even an 1100 is a "big twin" with big pistons.
3. In those three cranks, rrrr, rrrr, rrrr, probably only one of the two plugs has fired on the end of a compression stroke. Depends on the starter gear ratio, but these bikes do start quite well considering only one or two sparks affect starting.
4. Starter maintenance is a biggie: Clean the bendix, clean the gears, proper lube, all make a big difference.
5. Starter magnets DO come loose quite often on the older Oilheads. When this happens, the magnets actually ride on the rotor and cause magnetic and mechanical drag. Repairing this makes a HUGE difference as I found out.
6. On the older Oilheads, use that Choke lever properly, not just on, but turned up and held in the FULL ON position when cranking.
 
No sure about the Oilhead starter problem, but a Bosch starter on my Airhead was dragging on one of the magnets that had become loose in the housing. I just had it and another spare starter re-built.
 
This is late for the OP, but I had a persistent slow starting R1150RS. Thought it was the off brand battery, so I put an new one in. Hum, problem still present. So I pulled the starter apart expecting to see loose magnets.

The problem was in the gear reduction housing, there is a metal cover which holds the gears in place. The metal cover came loose and shorted out to the wires on the armature, causing it to turn over very slowly.
 
As a general comment, I use simple volt meter to do non-invasive tests in this type of situation. With the battery fully charged, and probes at the battery terminals:

Standing voltage with key off?
Voltage with key on?
Voltage while cranking?

I expect 12.6 or higher key off. Engine off, key on I expect something just over 12v. Cranking an Oilhead it is not unusual to see a low 11.something. Down in the tens I expect to find either a battery, a connection, or a starter problem. Or a really cold motor with heavy weight oil.
 
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