Schwinn Headset and Stem

[BooneM]

I have parts of an old Schwinn Tiger and a Corvette. The headset lock nut threads are both 1" but the opening for the stem is different on both. Looks like 13/16 on the Tiger and 7/8 Corvette. Both head sets are stamped Schwinn. No stamping on the lock nuts. I have a stem and handle bars for the Tiger (the smaller one) and a set of old Schwinn handle bars I want to put on the Corvette (the larger one) but I don't have a stem.
I tried to use the small stem on the Corvette when I noticed the difference in the opening size of the lock nut. Then when I tried to mount the handle bars I want for the Corvette on the stem from the Tiger the clamp would not fit the bars. The clamp area on the bars I want to put on the Corvette is just slightly larger than the clamp area on the bars that came with the Tiger.
I love the bars with the bigger clamp area (they are stamped schwinn) but I want to make sure i have the right stem for them. And the right lock nut to fit the stem.
Are there 2 different Schwinn Goose Neck sizes out there with different quill diameters and bar clamp diameters?
Are there different headset lock nut sizes? 1" female thread x ?
Can anyone solve the puzzle for me?
Any good Ideas where to get a stem and or lock nut to make things right?

 

[Jpromo]

I have a Corvette stem lying around that I could measure. It'd also be for sale if it's the size you needed :wink: It's in good rider condition as far as I remember.

 

[dougfisk]

The larger diameter stems are older, the smaller diameter is newer. At some point (maybe mid to late 60's?) they switched to the smaller diameter stem so they could use a thicker wall tubing on the steer tube for safety reasons. The smaller stem will work in the larger tube if you don't mind the look. You just need to be conscious of which is which when you are shopping. This is one of the small variations that keeps it interesting. After a few years of buying 2 or 3 parts in attempts to solve a problem you will have a nice parts stash. Don't ask me how I know this.

 

[BooneM]

Does a larger quill diameter equate to a larger bar clamp size?

 

[Bendix]

Does a larger quill diameter equate to a larger bar clamp size?

no.

quill diameter is independent of bar clamp size.