Help identify Excelsior flywheels

[Scooter6]

Good evening,
I need help to identify my Excelsior flywheels. I tried to used them in a 1920 engine, but they are too wide using the 1916 and up crank pin needed for the correct connecting rod spacing.

I am in need of 1916 and up flywheels. 1915 may be the same but I do not have 1915 parts book to know.

These flywheels are 2.790" measured across the outside at the crank shaft thrust faces when assembled with the 1916 and up crank pin.

I have found pictures of two types of single cylinder flywheels and neither look like these. I have not found any twin cylinder flywheel pictures that look like these.

Mine only have counter weights on the inside. Refer to attached images.

I think they are single cylinder flywheels because they have 1085 marked on each side weights. The single parts page shows 1085 for the single. I do not know why both of my left and right have the same number but it sure looks like both are marked 1085.

Please let me know what you know.
Thank you,
Scooter

flywheels outside.jpg flywheels inside.jpg

[exeric]

Looking in my Excelsior parts books, your flywheels are P.N. 1177 (right side wheel) & 1178 (left side wheel) for Excelsior Twins. Those numbers are good from 1908 - 1920 and probably to 1924.but there are different letter prefix's i.e. B, D etc. so there may be some differences that are not made clear in the parts books. I would bet the casting are the same for all years, but again, there could be minor changes. Fellow AMCA member, Gene Harper could provide better knowledge as he has been deep into many Excelsior motors. Also, I looked at the crank pin, drive, shaft and pinion shaft I have and they are worn out junk. They are hard to find in decent shape.

[gharper]

Eric, you're correct on the casting, same one used on all the twins. However, there may have been slight differences on how they are machined and significant differences in how they were balanced over the years. Scooter and I have been in touch.... His flywheels are odd, in that they have a counter weight on only 1 side of each wheel, which indicates a single. However, the 2 holes on either side of the crankpin are the shape of the twin wheels. So, once again, Schwinn was doing mystery things over the years. Scooter, you definitely need wheels that have counterweights on both sides of each wheel. I'll have to drag out my remaining spares and mock up a set of wheels and get a width dimension,

[Scooter6]

Good evening,
Thank you for the replies. I have also reached out to another member with the question if pre 1916 flywheel halves interchange with 1916 and up or if the alpha prefixes in the part numbers actually define a difference.
I am compiling as much information as I can and will publish what I find so futures can know. So far, I have not found a set, just one half that is likely to be twin and not sure of vintage.
Thank you for your efforts.
Scooter