RM125 B SWINGARM

[TM BILL]

If JohnnyO says they were available, that's good enough for me. The next question will be, how many 78 swingarms will be cut and shut and called optional 77 arms then?

I've followed this thread and I can see a lot of passion involved as this issue keeps getting kicked around.  And I don't want to buy into this arguement at all, in any way, BUT as a bystander, without any vested interest in the topic at all, what Brad has mentioned above is the bit that gets me.  How can a 78 arm be modified or retro fitted with a brake stay arm that wasn't originally there (as has already been mentioned in this thread a couple of pages back if I read it correctly) and be legal?  Surely that's not in keeping with the spirit of the rules and the competition?

Thats not what people want Simo ( not saying it wont happen) what people want is the right to use the 1977  ( available in 1976 ) optional arm .

The 1978 RM 125C arm does not have the brake stay fitted and also runs needle rollers and sleeves rather than the fibre bushes of the optional RM 125B arm . The fibre bushes from the B arm wont fit into the C arm as the bearing OD is slightly bigger .

You will always get some prick modyifing a C  arm i suppose but thats life , if somone feels that anothers arm is a modified C arm put up the money and have it checked 

[09.0]

If JohnnyO says they were available, that's good enough for me. The next question will be, how many 78 swingarms will be cut and shut and called optional 77 arms then?

This is all I said. Not against it. Just the simple fact that when its passed, how many turkeys will get a 78 arm and modify it to look like one. Not the end of the world statement nor is it such a huge deal if they do. But I for one do not think its the right thing to do.

[crs-and-rms]

i have two of the 125 alloy arms with the brake lug on them one i got in a parts lot that i bought  and one came on a early model c that i bought ,the owner of that bike had it from new its frame number is one of the first 30 from the list of frame numbers for the c

[Tahitian_Red]

i have two of the 125 alloy arms with the brake lug on them one i got in a parts lot that i bought  and one came on a early model c that i bought ,the owner of that bike had it from new its frame number is one of the first 30 from the list of frame numbers for the c

The fact that they were on the very early C models means they were built and available prior to December 1977.  RM125C's were for sale in the Fall of 1977.  I guess you would still need to prove that one was used or at least installed on an RM125B prior to the end of 1977.  Because they used up the supply on the RM12C's means either they didn't sell very well or they didn't have enough C arms ready to start the early production.

I got my RM125B in the Summer of 1977 and to be truthful I never knew this arm existed until I was browsing through the Aplha-Sports on line catalog 5 or 6 years ago.  I was too horny for a Fox/Thor or DG swingarm to think about anything else.


I've been on both sides of this fence.  I was one of the guys that voted for or against rules changes and I've requested rules changes (some passed and some didn't).  Take it as a challenge to prove you are right and then you can run the arm at your National level without worry if someone might protest you.

 

[Tahitian_Red]

Looking at old pics I've downloaded over the years I came across these two of a 1977 RM125B that looks to have the arm installed.  At first I thought the garage pic showed the swingarm with dried mud covering it, but look at the pic of the bike on his trailer.  Not enough proof, but if you could gather more photos, receipts and signed testimonials perhaps someone could get the powers-that-be to accept the arm as pre-78 legal.

I'm going to look at 78 RM125 magazine tests that may mention the C model comes stock with the optional B swingarm. 

[Simo63]

If JohnnyO says they were available, that's good enough for me. The next question will be, how many 78 swingarms will be cut and shut and called optional 77 arms then?

I've followed this thread and I can see a lot of passion involved as this issue keeps getting kicked around.  And I don't want to buy into this arguement at all, in any way, BUT as a bystander, without any vested interest in the topic at all, what Brad has mentioned above is the bit that gets me.  How can a 78 arm be modified or retro fitted with a brake stay arm that wasn't originally there (as has already been mentioned in this thread a couple of pages back if I read it correctly) and be legal?  Surely that's not in keeping with the spirit of the rules and the competition?

Thats not what people want Simo ( not saying it wont happen) what people want is the right to use the 1977  ( available in 1976 ) optional arm .

The 1978 RM 125C arm does not have the brake stay fitted and also runs needle rollers and sleeves rather than the fibre bushes of the optional RM 125B arm . The fibre bushes from the B arm wont fit into the C arm as the bearing OD is slightly bigger .

You will always get some prick modyifing a C  arm i suppose but thats life , if somone feels that anothers arm is a modified C arm put up the money and have it checked 

That's what I was saying Bill. I don't care if the optional alloy swing arm is used because if it was available in 1977 then great, go ahead and use one if you have one.  What I wouldn't like to see is people retro-fitting a brake stay to a 78 C Model swing arm to make it look like it's the optional B one.  I feel that is not in keeping with the spirit of the rules and the competition.

[Ted]

Simo, as Bill has stated B and C arms are different

[09.0]

And cannot be made to look like a b one? That's what I am saying because that would be able to be done knowing that there are some clever people out there.
Still you must understand and as much as I write it here I DONT REALLY CARE THAT MUCH. I'm stating what I would think is obvious yet you guys seem to think its unlikely because the two arms differ a little. Reality is some will just chuck one on and others will go to the trouble of making it look like the optional arm.
Then it will be one of those, of the 20 optional arms sold back in the day only 100 have survived.....

[TM BILL]

Brad your right but it doesn't stop at RM B and C arms

I could very easily ( and im a shit fabricator ) modify an RM C frame into an RM B frame

There is absolutley no difference between a 74 75 76 KX 125 frame yet 75 and 76 are not flow ons go figure

So to stop people using the genuine optional arm just in case someone modifys a C arm is ludicrous .

I have a genuine optional alloy arm for a 250B complete with brake lug ex factory 

[09.0]

So to stop people using the genuine optional arm just in case someone modifys a C arm is ludicrous .   

said me NEVER.

[TM BILL]

So to stop people using the genuine optional arm just in case someone modifys a C arm is ludicrous .   

said me NEVER.

You still got time to get ticket for this weekend  i will put the optional arm in the 370 for you  Its not gonna be the same without you ,Joan and Stewy  :'(

 

[Simo63]

So to stop people using the genuine optional arm just in case someone modifys a C arm is ludicrous .   

said me NEVER.

No, not said by Brad, rather said by me because of this post back on page one:

Yep I bought one from states without brake tag, got an alloy one welded on.

I'm not even sure Don was serious with this post but it highlights the potential problem.

But like Brad, I don't care what people do.  I don't even have a bike in this class, I was just commenting on what I saw as a potential issue if/when the alloy arms are accepted in pre 78.  All of a sudden there might be 100 of them when only 20 really existed (to use Brad's numbers  ) .. sort of like XY GTHO's ... at one stage it was reported there were more registered than were made 

[motomaniac]

I have an original RM125C , no lug for the brake stay and no roller bearings .It has the fibre bushes .

[Montynut]

So to stop people using the genuine optional arm just in case someone modifys a C arm is ludicrous .   

said me NEVER.

No, not said by Brad, rather said by me because of this post back on page one:

Yep I bought one from states without brake tag, got an alloy one welded on.

I'm not even sure Don was serious with this post but it highlights the potential problem.

But like Brad, I don't care what people do.  I don't even have a bike in this class, I was just commenting on what I saw as a potential issue if/when the alloy arms are accepted in pre 78.  All of a sudden there might be 100 of them when only 20 really existed (to use Brad's numbers  ) .. sort of like XY GTHO's ... at one stage it was reported there were more registered than were made 

The same applies to replica frames, engine cases and brake backing plates they are completely legal yet are made using modern material and processes. I don't think anyone suggests they should not be legal. If a part is identical in every way to an earlier bike then it would be legal. An RM125C engine is identical in everyway to an RM125B so can you run the 'later' engine. I would say yes because for all purposes it is a 1977 design

[motomaniac]

A C model cylinder and head have increased finning over the B model .Its easily identifiable.