different lighting coils?
They updated the HS40's in the 1973 calendar year to the deeper square top shroud and steel flywheel like the HS50's that were introduced in 1972, They eventually changed the entire small frame line to that steel flywheel design. I think along with a little more rotational weight it they also move a little more air.....well yours wont with that blade set :laugh:
Good thing to check on those is to grab or give a light tap to each magnet on the inside and check that they are attached well, They are pushing 40 years old now, I have found them come loose pretty easy and will ruin your day if they do. If any are loose they can be reglued ( I Like to use JB weld), just make sure they go in the same spot they came from including its polarity with the magnet next to it.
The actual lighting coil/ignition setup will be the same, just the flywheels are different
Good thing to check on those is to grab or give a light tap to each magnet on the inside and check that they are attached well, They are pushing 40 years old now, I have found them come loose pretty easy and will ruin your day if they do. If any are loose they can be reglued ( I Like to use JB weld), just make sure they go in the same spot they came from including its polarity with the magnet next to it.
The actual lighting coil/ignition setup will be the same, just the flywheels are different
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Thanks for the info guys much appreciated. I did see that rupp parts does have the replacement plastic fins so I will be ordering one soon. Do you know if there's a difference in performance between the old flywheel style and the newer one? I would think the older one being lighter would cause less drag and better performance but just a guess.
Might want to rethink ordering from Ruppparts....sadly you may never get the parts (do some searching on here and you'll see what I am talking about)
I don't think you will notice much of anything, I converted an HS50 over to the old style shroud and aluminum flywheel to keep it period correct looking for the bike. If you do swap things around you need the correct shroud to go with the wheel and also keep in mind that the round top shroud for the aluminum lighted wheel MUST have studs for the recoil to mount to or be altered so the fins clear whatever you use to mount the recoil or the fins will look like the ones on your steel wheel...and they unfortunately are not replaceable!!!
I don't think you will notice much of anything, I converted an HS50 over to the old style shroud and aluminum flywheel to keep it period correct looking for the bike. If you do swap things around you need the correct shroud to go with the wheel and also keep in mind that the round top shroud for the aluminum lighted wheel MUST have studs for the recoil to mount to or be altered so the fins clear whatever you use to mount the recoil or the fins will look like the ones on your steel wheel...and they unfortunately are not replaceable!!!
Thanks for the tip on rupp parts and info on the different flywheel performance. I'm not gonna switch anything around was just curious if there was a difference in power as I have both style lighted motors I think the fins got broke on this one from the screen between the shroud and flywheel because the cover does have the flat bolts that are permanent with the threads facing out.