Frame to Motor Braces

[Tim McKinney]

Exactly what function do these braces perform and are they really needed on my 74 Harescrambler. They make doing any carb work a real pain in the butt and with the wiring from the motoplat to the coil and light ting block running through the small welded rings on the back side are really not that easy to remove? Sure would make carb work easier without them?

OLD BIKES RULE!!!

[tomale]

Hi Tim,
yea they do make things tough. There is some debate about that but I am not about to take sides on that one. It is not all that hard to take the right side arm off when it is time to do carb work, Loosen the large bolt on the engine and remove the bolt on the frame. swing it forward and for most things you do with out completely removing it... It has been awile but you should be able to do everthing but removal of the carb. To change jets move the brace forward, loosen the claps on the carb and loosen the cap on top of the carb. Now you should be able to turn it to the right or was it to the left. give it a try, by the way, do a search using the seach mode and you should be able to find several guys weighing in on the need of theses braces...

Thom Green,Still crazy after all these years!
76' 250 MC5 (orginal owner)74'
250 hare scrambler (project bike)

[joe novak]

Hello,  I have had several Penton (SACHS) CMF's which had the frame-to-engine braces.  I, too, had asked the question of their function.  Yes, they do make any carb work more difficult.  Those braces are used to triangulate the engine into the frame, which makes the frame more rigid (less flex).   Too much frame flex leads to failure of metal.  Hoping to not offend anyone, but the early CMF's were prone to frame failure.  I have seen many cracked frames, and several entire steering heads broken off the frame.  One of my personal CMF Pentons had a cracked frame (gusset) near the steering head.  The CMF frames are built using thin-wall tubing of chrome moly steel.  By it's nature, it is strong steel.  Somewhere in my Penton pile, I have the metal analysis of a CMF Penton frame (performed by a popular American steel company).   I recently found a handful of those brackets in my garage.  Hey, that's where, "What's in your garage?" originated!   Anyway, they will go back on my old CMF Pentons in the near future.  I will fabricate new brackets for those CMF Pentons which do not have them.  We all know how old metal (and riders) becomes more brittle due to fatigue with age.  joe