Is there any difference between a 40SR and a 40FSR and for parts ( gaskets, bolts, carb.)
thanks
wattmeter[8D]

the fsr came with a bigger bore carb

Do know if the gaskets and bolts were the same?
wattmeter

Hmmm...well this is the back end of an SR....
Gaskets and screws will be the same because the FSR used the SR crankcase.

It's been close to 20 yrs since either of thiose engines were made. Parts are scarce for either one

Fortunately bearings and rings are still available from other sources

There are lots of NIB versions of these engines on the auction sites. If one is truly dedicated to this engine design, buying NIB engines and using them for parts isn't such a bad idea. Even used versions can be very helpful. I started to go nuts on the old FSR engines, but then I remembered the Enya CX, X and XF engines and jumped on them instead. I love the old OS FSR engines, but they are grossly outclassed by the Enya engines that I previously mentioned. Oops! I shouldn't have said that...<G>


Ed Cregger

Ed is just looking to stir up trouble.

me too[>:]...eat yer heart out Ed.......2 NIB 40FSR's....70 bucks each a couple months ago.
best engine series ever from OS

Good catch. Only problem Isee with them is if they crash hard and the muffler bolt holes break out of the cylinder.

i don't intend to crash them.........actually, i haven't crashed anything in quite a number of years now

i know what you mean tho, i just dream that someday OS will wake up and make a fine engine like these were, but you know what they say about daydreamers

Good for you on getting those FSR's at such a good price and condition. I have managed to accumulate one .45 FSR (ringed). Most of the ones that I have seen for sale have been non-ringed, which are good engines, but difficult to restore, should the need arise. I might have more than one of the .45 FSR's stowed away come to think of it and I do believe that one is ABN and pumped (Perry). Gotta go check my stash to be sure.


Ed Cregger

ED,

yep these were ringed versions.
although i never owned any of the famous ABN versions, i still refuse to buy them.

To clear things up, the O.S. Max .40 FSR IS a .40 SR. If the carburetor was mounted in front of the engine, you had a .40 FSR, if the carburetor was mounted in back of the engine, you had a .40 RSR. Same for the .61-size engine.

Well just to muddy the waters a little , the 40SR came out in '73 with rear drum induction in either pylon form for RC or rat race for CL. My engine in the photo above is the CL rat race engine. The crankcase has SR moulded underneath the exhaust port. In '75 OS made a front induction sport engine based on the same crankcase and called it FSR where the F presumably stands for Front induction (just a guess though) but the crankcase still had the SR under the exhaust. The RSR designation started when the rear induction models changed from drum valve to disc valve.