sprag sprague clutch easy fix diy

[The Mighty Gryphon]

I had a problem with the sprag clutch after doing a head job and reassembling with moly assembly paste.  Never put anything with moly in it in the engine  After running fine for a week the sprag stopped working.  The moly paste had migrated into the oil.

I did an oil change with plain old 10W30 and put a full bottle of Sea Foam in the engine.  Did a backspin to engage the sprag clutch and took it out for a 20 mile run.  Came back and did another oil and filter change, and knock on wood, the starter has worked perfectly in the month since.

[Conrad325i]

That is good to know. I have yet to ride my new bike further than around the block because Im waiting on tires. But I have to tap on the spraque every single time I want to start the bike. And every time ive started it I have let it get up to opp temp... I guess it needs high rpms to fully lubricate that thing again...

Unfortunately I think mine is really really gummed up.

Like it was having problems and then the prev owner let it sit outside for 15 years lol

[The Mighty Gryphon]

Drain the oil and replace with some cheap 10W30 and a full bottle of Seafoam.  Run it hard for a half hour or so and do an oil change.  I was amazed at how dirty the oil was for such a short run time.  Sprag clutch is still working properly.

[Conrad325i]

As soon as my tires get here/mounted/balanced I will do just that. Thanks for the tip, gryph.

[Conrad325i]

So in a single post:
Step 1: Drill and Tap the crankcase to accept 1/4npt and buy a plug to go in it.
Step 2: Open oil filler cap
Step 3: Pour in 1/2 bottle seafoam
Step 4: Go for a ride
Step 5: Jump for joy when you can restart the bike without pulling your air filter and banging on the sprag        housing.

[The Mighty Gryphon]

Don't leave that Seafoam in there too long.  It thins the oil and that isn't good for the rubby parts.

[Martin]

No need for drilling I found this on another site, read it all.
 http://k-bike-knowledge.000webhostapp.com/mechanical/sprag_clutch/starter_clutch.htm
Regards Martin.

[thecableguy]

One other thing.  A weak starter can cause the sprag to slip. 

I was having occasional horrid-sounding sprag noises and I tried several of the cleaning methods described here.  After months of trying to fix it that way, on a hunch I took a look at the starter brushes.  Immediately ordered a rebuild kit from the guys at Euromotoelectrics.  Rebuilt my starter and never had the sprag squeal again.

Just another thing to look at.  And rebuilding one of these starters is easy and cheap.

Jim

[detbmw]

The ebay link no longer works for the flushing oil. Was it Rislone? And do you add a quart, or fill it with just Rislone?

Thanks!

[Laitch]

Was it Rislone . . .? And do you add a quart, or fill it with just Rislone?

Considering the post with that link is seven years old, it might be more effective if you sent Texbid a PM through this site for a personal answer which you could post as an update for everybody.

[Texbid]

https://www.ebay.co.uk/itm/Engine-Flushing-Oil-Flush-Fluid-Cleaner-For-Petrol-Diesel-Engines-5-Litre-5L-/373537080247?_trksid=p2349624.m46890.l6249

Any cheap flushing oil will do.

[Laitch]

There's a dedicated member right there. ⬆︎

[Texbid]

Just trying to help.  I sold the brick many years ago, but remember the utter dismay at considering a full engine teardown for a simple fix.

And frankly I was quite shocked when I saw a response to this diy fix.  Good luck.