Rm 125 swinging arm

[Ted]

what exactly is differant between the B and C swingarms other than the brake stay?

If you are talking the difference between a optional 125B aluminium arm and a aluminium 125C arm there are two things that differentiate. Three if you include the brake stay mount.

 So simply welding a mount to a C arm will end in tears if the bike podiums. MA are fully aware of the differences and i believe will disqualify anybody found cheating.

For the information of all the optional arm weighs exactly the same as the standard steel arm when bolted to the bike. The only performance gain to be had would be to prove it didn't flex quite as much as the steel one. Clutching at straws there.

My advice would be to forget the alloy arm and spend your money on fitting the steel arm with no play at the swingarm pivot bolt, gusset the frame and getting your suspension set up on a dyno

[relfy]

Ted ,,,, YOUR BAAAAACK !!!!!!!!

[HeavenVMX]

what exactly is differant between the B and C swingarms other than the brake stay?

I understand that it is reasonably obvious once you look at the arms that the parts of each version of the swingarms are welded together in a different order (which parts sits on top and which weld was made first basically ie weld on top of weld or where they pass over each other) so that just welding a brake stay anchor on is obviously an addition as the 'C' arm was assembled without the brake bracket. The very early 125C's had the brake bracket in place and if you have a look at early promo photos the bracket is in place but not used but these swingarms are also slightly different again.

That is how it was explained to me by a local collector who has several of each of the three versions and also has the arm fitted to the Rahier bike that was here around the same time which is very different again.

[KTM47]

what exactly is differant between the B and C swingarms other than the brake stay?

If you are talking the difference between a optional 125B aluminium arm and a aluminium 125C arm there are two things that differentiate. Three if you include the brake stay mount.

 So simply welding a mount to a C arm will end in tears if the bike podiums. MA are fully aware of the differences and i believe will disqualify anybody found cheating.

For the information of all the optional arm weighs exactly the same as the standard steel arm when bolted to the bike. The only performance gain to be had would be to prove it didn't flex quite as much as the steel one. Clutching at straws there.

My advice would be to forget the alloy arm and spend your money on fitting the steel arm with no play at the swingarm pivot bolt, gusset the frame and getting your suspension set up on a dyno

Ted  You missed the point of my post.  If you have the latest VMX Mag read the bike tests in there.  While a C arm stands out on a RM125B when it is on something else it may slip through.

Of course the question now arises.  If MA is going to allow replicas of components that were available back in the day, why isn't a modified C arm just considered a replica.

Also I see Manly fluked another win.  Roosters were robbed.