Topic: Synthetic oil and CB750 starter clutch. Any problems?

[banzaibob]

I broke in the rebuilt CB750 (with 849cc kit) with regular 10-40 mineral oil. Last week or so, I changed it to Amsoil 20-50 synthetic.  Yesterday I went out and zing!  The starter motor spun all the gears but the rollers in the starter clutch would not grip.  I took it apart today and the metal has no wearing, galling, glazing or chunks.  I have used Amsoil for a long time.  I'm ambivalent insofar as any quality motor oil will work just fine in most applications. I'm wondering if anyone else has had an issue with synthetic oil and starter clutches? 

[gto_ron]

I use Royal Purple 15W-40 in my K6 with no problems.

[jpfrk2001]

I know you might hate doing this, But drain some synthetic oil, pour a bit of seafoam and Marvel mystery oil and use the kicker in the meantime. Maybe its just a bit dirty and needs to be flushed out after the break in oil? I don't know?

My starter clutch spun on me. put in some seafoam and Marvel. Ran it for awhile. Clutch starter came back. Put 50 miles on the bike, Immediatly flushed the system for new oil and filter, for 100 miles. changed it again, for 250 miles. Changed again and about to hit 500 miles on this oil. Plan on changing AGAIN, then finally going to Royale Purple for the long haul.

[scottly]

Yesterday I went out and zing!  The starter motor spun all the gears but the rollers in the starter clutch would not grip.

Had the same thing happen shortly after I bought my 750. Rode the bike to work, then at the end of the workday, hit the starter button and zing. The rollers were gripping fine; the rotor was spinning on the tapered end of the crank! The PO hadn't properly tightened the rotor bolt.

[banzaibob]

No, the engine has less than 500 miles on a total rebuild, the engine is clean.  The rotor was not spinning on the shaft, it was tight on the taper. 

One of the reason I am asking has to do with Amsoil specifically.  I had two Harley twin cams whose lifters would bleed down using Amsoil.  Regular mineral oil, no problem.  I also had an FT500 Ascot that had an automatic cam chain tensioner that failed because it required friction to hold two adjustment blocks together.  The lubricity (right word?) caused them to slip.  Switched back to dinosaur crap, no problem. 

The starter clutch on the CB750 requires friction.  Hmmm.

[dave500]

diesel engine oil.

[Wobbly]

After the initial oil change back in 77, my Honda has not had anything but full synthetic oil--for 36 years now.

[Bodi]

Never had a starter clutch issue with Amsoil. I don't always use Amsoil but often do. I've used only synthetic oil for many (20+?) years except on break-ins after rebuilding.