Sprague clutch cold problem

[Bill]

My new to me 88 K100 has shown its first problem so advice is requested.   Since  buying this a month ago I have been starting it and running for 10-15 minutes to circulate  injector cleaner through the fuel system.  Today the starter runs but does not engage.  Do I wait until it is warmer and hope the sprague clutch frees up, or perform the 20 Minute DIY fix detailed in a previous post, or is there another possibility ?

[johnny]

greetings bill...

running a few minutes now and then is not good for the brick... its better not to run it at all... butts if you must... i would run it up and down through the gears while it sits on the center stand spinning the rear wheel... till it getts hot enough for the fan to kick on before thinking about turning it off...

j o

 

[Bill]

Running 15 minutes got the temp guage half way.  When I get it started again I'll certainly run it harder and longer until the fan kicks on.  Problem now is getting it engaged  :dunno2:

[Martin]

Bill put a bit of heavy detergent additive like Rislone or CD2 Engine Oil Detergent into the oil as per directions. You don't have to put fresh oil in to do this.  Place the bike in gear and rock the bike backwards. If the starter doesn't free up you can push start it, then go for a long long ride, run until your nearly out of petrol. Its best to have someone follow you with spare petrol, park on a decent hill, fill up the bike and try to start it. If it doesn't start roll it down the hill and restart. Go for another long ride, you can do this over more than one day. If the problem is now fixed change the oil and the filter and run a fully synthetic oil. If this doesn't work you may have to replace the Sprague clutch.
 Regards  Martin.

[rbm]

Martin,  It's mid-winter here up North; no chance of going out on a long tour to wash the sprag until spring time arrives.  If the cold ride doesn't get you, the salt on the roads will kill the aluminum and ruin fork seals.

Shouldn't be running the bike for short intervals like that, Bill.  Just leave it for warmer weather.  When that comes, do what Martin suggests.

[Bill]

The hope was to run it longer this time. get it warm enough for a proper oil change.  Come spring I want it ready to ride    Guess I'll get the other stuff done while I ponder the 'other method ' I read about.

[The Mighty Gryphon]

Here's another two cents for you, Bill.  Last week my k100 did the same thing.  Wouldn't engage the starter clutch.  Spent about an hour screwing around with it to no avail.  Put the charger on the battery and left it for a couple days.  When I came back it started right up.

I suspect that with the cold temperatures the oil can get a little thick and won't let the pawls rotate like they're supposed to.  After a couple days, enough oozes out to free things up and the starter works again.  Even if the daytime temperature is above freezing, the inside of the engine can hold the cold of the night before.

Like Johnny says, if the engine doesn't get real hot, that clutch can cool off before all the oil drains out and turns to goo.  This is especially true in the intermediate section where the sprag lives.  That part of the engine can be pretty slow to come fully up to temperature.  This time of year it's better to only fire up the engine every couple of weeks, and run it through the gears on the center stand to move the oil around the transmission and the final drive.  Get it all the way up to operating temperature before you shut it down.

[TimTyler]

I don't think it'll hurt to add a bunch of your favorite engine oil detergent and run the bike up and down the street for a half hour once a week until the temps warm up. The idea is to get the engine hot and slosh all the oil around. The starter clutch is at the top of the engine and is not soaking in oil.

[Bill]

Im going to wait until we gwt some sustainef warmer temps before I run this anymore. Thank you all for your wisdom in this.

[Martin]

Robert I forgot about the winter you guys get, I don't think I could stand it. Even when I lived down South you could ride all year round. Bill pack up all your belongings and move to California or Miami then do what I suggested.
Regards Martin

[Bill]

By the time I did that it would be warm here !

[Bill]

Problem solved itself once the temps warmed up  .  Ran it up and down the street a couple of times and got the temp light on but the fan does not appear to be working  :dunno2: ..... probably stiff from lack of running at temp.  Still lovin' this bike  :riding:.  Spring can't come soon enough  :musicboohoo: :musicboohoo:

[Martin]

Bill still run some detergent additive, then switch to a synthetic or at least semi synthetic oil and change the filter. The bike has given you a warning so take heed.
Martin. :clap:

[Bill]

Warning has been duly noted  :mbird.  I'm just happy I don't have to disassemble big time to fix or drill a hole in it as detailed in another post.  A risolone or similar treatment is on the todo list as well as cooling fan check.

[Martin]

Bill BMW cooling fans are crap, the brushes tend to melt and road grime gets in. Sixteen years ago a second fan was $200.00 Au. I ended putting a fully sealed Davies Craig Car fan in its place with a override switch. If I get in heavy traffic I just switch it on for a short time, it still works automatically but it is reassurance to be able to check it. My switch is mounted on the dash board, but if you just want it as a check switch, you can mount it anywhere.
Regards Martin.

[rbm]

Bill,  Test the fan from the relay box.  Pull out the temp relay and perform some tests. Schematic of the connections is below:



Jump #45 to Pin #A2 the fan should operate (it's bypassing the relay contacts and emulating the relay's function). If not, you have a broken fan.

Ground Pin #A3, you should get the dash indicator light (simulates an overtemperature event).  If not, you have a burnt out indicator lamp.

Ground Pin #E, you should get the fan operating and the dash light (tests the functioning of the relay).  If not, you have a faulty relay.

In the diagram above, there are a couple of switch circuits in blue.  You can install either Solution #1 or Solution #2 (not both) to provide a fan over-ride switch, to turn on the fan whenever you want.

[The Mighty Gryphon]

Bill, chexk out this thread on fans. 

http://www.motobrick.com/index.php/topic,4313.0.htm

Go to reply #18 on December 20, 2014.   Poster describes an easy install of the $60 Spall fan.  I can attest to the ease of installation the way he describes.  I put that fan in my K100.  Took about three hours, including the bodywork removal.