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Discussion Starter #1 (Edited)
Off to the Bike Show in DC this morning......get on and press the starter...it responds with a healthy, gentle "whizzzzzzzzz" but doesn't catch and turn the motor. Its like nothing I've heard before. Not a flat battery (I know THAT sound), not starter relay (its the new model and it switches off/on with the starter button OK)...I suspect its something in the starter itself where its turning, but not engaging the flywheel (or whatever it engages to start turning the actual motor).

Any ideas? Sprag clutch...but why would it fail with no warning ever before. It has sat unturned for 6 weeks.
 

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Sprag Clutch

Unfortunately I think you've hit the nail on the head...

Look in the HOW and see what you can find on it...

Maybe PM David Shealey and see what his thoughts are on it...

I understand it's quite a tear down to get to it so you've got some work ahead of you...

Good Luck

John
 

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Discussion Starter #4
OK, thanks guys, I tried reverse, no help. CD-2 may be the answer plus a push start on the VERY FLAT Philly streets.
 

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grifscoots said:
Try putting it in reverse and using it. It's a function of the starter motor and may free the sprag clutch. Put some of that engine cleaner, I believe it's called CD-2 in it. You may have to get a push start if using reverse doesn't free it up.
Ole Toad won't start in reverse. I use that feature when overnighting in a motel/hotel. Course, next morning, panic sat in when I tried to start ole Toad and nada.
 

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Starter problem

I had a similar problem with my 1150RT at about 6,000 miles. By putting the bike in gear and rocking a little it would start. It turned out to be a badly cast flywheel.
 

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rmg08057 said:
Off to the Bike Show in DC this morning......get on and press the starter...it responds with a healthy, gentle "whizzzzzzzzz" but doesn't catch and turn the motor. Its like nothing I've heard before. Not a flat battery (I know THAT sound), not starter relay (its the new model and it switches off/on with the starter button OK)...I suspect its something in the starter itself where its turning, but not engaging the flywheel (or whatever it engages to start turning the actual motor).

Any ideas? Sprag clutch...but why would it fail with no warning ever before. It has sat unturned for 6 weeks.
Yep, Sprag clutch.

Hope you can get it running again and put some CD-2 in it in hopes of cleaning the buildup out of it. It will take some time for it to work, so hope you can get it started now, and for the future thousand miles or so.

Try putting it in gear and rocking it back and forth, then try starting it again. Rocking the engine will rock the sprag clutch assembly, and often will free up the sprags enough for them to grab again. If it gets so that even that won't work, you are in for one of the worst jobs possible on the LT. Ask me how I know that!
 

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Cd-2

So David,

I'm taking from this that the perodic use of some CD-2 will help to keep the sprag clutch clean and working over the long haul ???

How much, ? How often ? All the time ?

Thanks

John
 

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grifscoots said:
Try putting it in reverse and using it. It's a function of the starter motor and may free the sprag clutch. Put some of that engine cleaner, I believe it's called CD-2 in it. You may have to get a push start if using reverse doesn't free it up.
Reverse won't do anything at all, as the only thing that will rotate the sprag cage assembly is to rock the engine over by putting it in gear and rocking the bike back and forth. Only engine rotation will do that. When I had mine start doing it, that would free the sprags enough to get it starting again. Unfortunately, this only worked for a few days, then it would not engage at all. Running the starter only spins the inner race of the sprag clutch, the sprag cage assembly is in the outer race, which is geared to the crankshaft.

Push starting the bike is easy, if you have someone to push it for you. Put it in second gear, have them push it up to a fast walk speed, then let the clutch out and pull it in again as soon as the engine starts.
 

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Sprague Change

I just performed this fun job today. It is a big job . When removing my replacement bearing cage out of the parts rapper 10 of the dam bearings with the tiny springs fell out. Spent the better part of a hour reinstalling the microscopic springs and bearings into the cage.
 

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Discussion Starter #13
Dang it Peter, I told you to call me whenever you were doing the sprague clutch thingy next time....you should have rung me yesterday!
:)
 

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Discussion Starter #14
David + Pete

Is it your impression that the CD-2 thing is only temporaryily effective? I read another thread where several people with the same problem who used CD-2 ran the bike for longer periods. If its only deposits and not wear, then why wouldn't a few rapid oil changes + the CD-2 thing clean it all up permanently?
 

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rmg08057 said:
David + Pete

Is it your impression that the CD-2 thing is only temporaryily effective? I read another thread where several people with the same problem who used CD-2 ran the bike for longer periods. If its only deposits and not wear, then why wouldn't a few rapid oil changes + the CD-2 thing clean it all up permanently?
CD-2 can be a permanent fix. The problem with the sprag clutch is that it does not take much carbon/varnish buildup to cause the little sprags to stick in the cage. They have to move freely to lock up on the inner race when the starter motor turns it. They then release and allow the outer cage to rotate freely around the inner race when the engine starts and is running faster than the starter is turning the inner race. If the sides of them stick in the cage they are retained in, they will not pivot down freely and lock up as needed.

Running CD-2, which is a stong oil detergent additive, can loosen and flush out the carbon/varnish, freeing the sprags. Once clean, they will continue to operate properly until build-up occurs again.

I would advise running a bottle of CD-2 (or Rislone oil detergent additive) every 4th or 5th change to help keep the sprag assembly free.
 

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murray said:
I just performed this fun job today. It is a big job . When removing my replacement bearing cage out of the parts rapper 10 of the dam bearings with the tiny springs fell out. Spent the better part of a hour reinstalling the microscopic springs and bearings into the cage.
Glad to see someone else has experienced this thoroughly joyful task besides me! :D :D

I think you will now agree with me, that when BMW starts assembly of the LT, they first place the sprag clutch on the assembly line, then assemble the rest of the bike around it. :rotf:
 

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DaFlake said:
David,

Would the CD-2 be compatible with synthetic engine oil?

TIA
Ramon
The bottle does not differentiate, and I checked the website (used to be Alemite, now distrubuted by Turtle Wax) and nothing there either.
http://www.turtlewax.com/main.taf?p=2,2,2,6

I don't see any reason it would not be compatible, since synthetics are still mostly petroleum based, and are compatible with standard dino oils.

It's purpose is to dissolve and disperse buildups, which is the problem with the sprag clutches.
 

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Thanks, David. I know I'm going to go out and get a bottle of CD-2 as preventative measure.

Ralph, I'm keeping my fingers crossed for you.

-joel
 

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Discussion Starter #20
Joel, I need your help to push start the beast on the streets here. Its really flat, and I can't get a paasserby because they all have a hangover after the Eagles game.

Thanks everyone for your help.
 
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