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1979 Starter problems, have some ??'s

lvin4jc

JoeBobber
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My bike has starter problems. 8/10 times that you push the starter button the starter sounds like gravel in a blender. Not only is this unpleasant, it also doesn't attempt to start the bike. 2/10 times the starter fires the engine right up.

Two questions about this;

#1. Does this sound like I need a new starter or a starter clutch?

#2. What years of starters interchange? Is it a SOHC / DOHC thing or are there specific years that will and won't work for me?

Oh, and I guess this is cheating since I said two questions, however, since it might be related to starter interchange i'll fold it into this thread. How do I tell what letter comes after CB750 on my bike? I see several variations, CB750A, CB750F etc. etc.

Thanks!
 
Starter clutch. They are well-known for issues on these. '79-83 DOHC (750,900,1000,1100) ONLY interchange. The outer cover often loosens at the 3 bolts that hold it on and the rollers and spring inside commonly go bad. If using automotive oil the friction modifiers that replaced zinc due to EPA changes can make the oil slick enough so that the rollers slip instead of locking up to drive the clutch, the noise you hear. Simply changing oil sometimes fixes it, use motorcycle specific oil with zinc, JASO spec IIRC. Valvoline makes some but expensive since it is oil that technically bypasses EPA spec, you gotta pay extra for that.

A motor in crap tune so that it barely tries to pull away from the starter at startup will do it too, tries to start but not positively and then unloads the rollers to then skid loose. Tune engine or fix it to cure.

Look at the stamped in steel or riveted plate on steering head for the letter you're looking for. Side covers if not painted say too.
 
Starter clutch. They are well-known for issues on these. '79-83 DOHC (750,900,1000,1100) ONLY interchange. The outer cover often loosens at the 3 bolts that hold it on and the rollers and spring inside commonly go bad. If using automotive oil the friction modifiers that replaced zinc due to EPA changes can make the oil slick enough so that the rollers slip instead of locking up to drive the clutch, the noise you hear. Simply changing oil sometimes fixes it, use motorcycle specific oil with zinc, JASO spec IIRC. Valvoline makes some but expensive since it is oil that technically bypasses EPA spec, you gotta pay extra for that.

A motor in crap tune so that it barely tries to pull away from the starter at startup will do it too, tries to start but not positively and then unloads the rollers to then skid loose. Tune engine or fix it to cure.

Look at the stamped in steel or riveted plate on steering head for the letter you're looking for. Side covers if not painted say too.

Will this from Vintage CB750 work?

Starter Clutch Rebuild Kit
Add to Cart
Starter Clutch Rebuild Kit
Starter Clutch Rebuild Kit - KIT contains: 3 pc. Rollers (15 x 13),
3 Caps 15.5 x 6.2 + 3 springs.

Fits: Honda CB750F (1979-82) Supersport,
CB750L (1979) Limited Edition,
CB750C (1980-82) Custom
Part #: 24-5001
 
Ok, not sure about the letter i'm looking for. My VIN doesn't start CB750 like I see others, at least SOHC bikes did.

My VIN is RC012018873

That VIN is stamped on the right side and is confirmed on the riveted tag on the left side.

Is that weird?
 
The riveted tag clearly mentions the model with the letter if not painted over. As in CB750(X). Forget the VIN.

Regardless, the starter kit there fits ALL DOHC 750,900,1000,1100 '79-'83, they all use identical starter and clutch.
 
The riveted tag clearly mentions the model with the letter if not painted over. As in CB750(X). Forget the VIN.

Regardless, the starter kit there fits ALL DOHC 750,900,1000,1100 '79-'83, they all use identical starter and clutch.
IMG_20160315_230151711 (1).jpgIMG_20160315_230042127.jpg

Is there another riveted tag on the stem? This is the one I have.
 
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