'75 250 vintage legal?

[imported_n/a]

Thanks, Andy.  I'll be watching for any updates on this topic.

Glenn

 

[Mike Lenz]

I asked this question to AHRMA a few years back also after seeing Berry Higgins using those forks. AHRMA told me to ask Berry Higgins for an answer to this Question!! That answered my question!








 

[Mike Lenz]

I asked this question to AHRMA a few years back also after seeing Berry Higgins using those forks. AHRMA told me to ask Berry Higgins for an answer to this Question!! That answered my question!








 

[metalkfab]

I checked the measurments on both styles of forks (bladed and non-bladed)and found both styles measure the same.However I did find that the bladed forks had a longer spring and smoother action with identical qty. and type of fork fluid as non-bladed forks.Also checked the AHRMA rule book and couldn't find a mention how tech would check travel of forks.

[imported_n/a]

Thanks, gentlemen.

Now, does anyone have an NOS or used left slider for the "bladed" 35mms?  That's the part I need.

Glenn

 

[Mike Lenz]

Glenn I have one. Which side? The finned forks have longer dampening rods which will give more travel with the same length top out spring. However they also raise up the front of the bike by about an inch. Which is not to good for turning, at least for mx.

 

[imported_n/a]

Mike, in the set I have, the left leg binds in its travel, which I'm guessing is a bent slider.  The tube is straight.  If you would e-mail me with specifics, I would like to do the deal.

Thanks.  

Glenn
[email protected]



 

[lobo6y]

Mick, POGers,

I am the AHRMA MX Tech Chief (West of the Mississippi) and I'd like to help with this one.   If you look in the 2003 AHRMA Handbook you will NOT see the '75 Penton/KTM listed as "eligible like- design" models in the Sportsman 250 class. HOWEVER, AHRMA has allowed certain of these 75s to compete as "like design" in the past. Until now, nothing has been written to clarify that exception. I'm working on the proper rules and language for written inclusion in the handbook. Meanwhile, as the Tech Inspector, here is what we currently are planning on enforcing for 75 Penton/KTM 250/400:

Unfortunately, Penton/KTM, like most of the European Marques of that period, did not stick to "model year" introductions, that makes the "like design" issue harder.
LEGAL FRAME:  The MC5 frame is NOT legal. There are 3 possible frames in consideration here.  Either of the two pre-75 frames are legal.  Both the early frame and the hi-breather are legal. They are most easily recognized as legal if you look at the frame member in the rear section that goes from near the foot-peg mount, up to the seat or upper shock mount.  If this section is STRAIGHT and of either the earlier round stock, or later oval stock (with flat sides), the frame is LEGAL for Vintage.  If this frame section is not straight, it is an MC5 configuration and not legal.
LEGAL FORKS:  Again, we are dealing with 3 potential stock KTM models.  The earliest in 74 are the 35mm Cerianis.  The next version were 35mm Cerianis, but built to KTM specs, with a different appearance (the blade), with a little over 7" of travel.  They are legal, but MUST  be limited to 7".  The last version we see are the leading axle (Marzocchi) forks which are NOT legal.
Whatever legal configuration you use for forks and rear suspension, the wheel travel (not shock shaft travel) must be 7" in front, and 4" in the rear.  We don't care which mount you use on the swingarm (although it makes it harder for us to figure your actual wheel travel).

For any of the "like-design' 1975 exceptions, AHRMA has relied upon historical written data from the era, as well as qualified experts on a marque in that era. That is why Barry Higgins was referred to as a primary source of information.  I am actively researching the Penton/KTMs on this issue and intend to get this in writing so there are no doubts.  IF ANY OF THE DISTINGUISHED POGers HAVE DATA ON THIS issue I will be VERY GRATEFUL, and we will all benefit!  I will get it to the Eligibility Committee which ultimately sets these rules. Please let us know if you have different info!

Cheers, Dave Janiec
AHRMA 6y
AHRMA West MX Tech Chief
Mick, POGers,

I am the AHRMA MX Tech Chief (West of the Mississippi) and I'd like to help with this one.   If you look in the 2003 AHRMA Handbook you will NOT see the '75 Penton/KTM listed as "eligible like- design" models in the Sportsman 250 class. HOWEVER, AHRMA has allowed certain of these 75s to compete as "like design" in the past. Until now, nothing has been written to clarify that exception. I'm working on the proper rules and language for written inclusion in the handbook. Meanwhile, as the Tech Inspector, here is what we currently are planning on enforcing for 75 Penton/KTM 250/400:

Unfortunately, Penton/KTM, like most of the European Marques of that period, did not stick to "model year" introductions, that makes the "like design" issue harder.
LEGAL FRAME:  The MC5 frame is NOT legal. There are 3 possible frames in consideration here.  Either of the two pre-75 frames are legal.  Both the early frame and the hi-breather are legal. They are most easily recognized as legal if you look at the frame member in the rear section that goes from near the foot-peg mount, up to the seat or upper shock mount.  If this section is STRAIGHT and of either the earlier round stock, or later oval stock (with flat sides), the frame is LEGAL for Vintage.  If this frame section is not straight, it is an MC5 configuration and not legal.
LEGAL FORKS:  Again, we are dealing with 3 potential stock KTM models.  The earliest in 74 are the 35mm Cerianis.  The next version were 35mm Cerianis, but built to KTM specs, with a different appearance (the blade), with a little over 7" of travel.  They are legal, but MUST  be limited to 7".  The last version we see are the leading axle (Marzocchi) forks which are NOT legal.
Whatever legal configuration you use for forks and rear suspension, the wheel travel (not shock shaft travel) must be 7" in front, and 4" in the rear.  We don't care which mount you use on the swingarm (although it makes it harder for us to figure your actual wheel travel).

For any of the "like-design' 1975 exceptions, AHRMA has relied upon historical written data from the era, as well as qualified experts on a marque in that era. That is why Barry Higgins was referred to as a primary source of information.  I am actively researching the Penton/KTMs on this issue and intend to get this in writing so there are no doubts.  IF ANY OF THE DISTINGUISHED POGers HAVE DATA ON THIS issue I will be VERY GRATEFUL, and we will all benefit!  I will get it to the Eligibility Committee which ultimately sets these rules. Please let us know if you have different info!

Cheers, Dave Janiec
AHRMA 6y
AHRMA West MX Tech Chief
n 75
Forks:  No leading axel (Marzocchi)

 

[tlanders]

More than likely AHRMA will defer to Barry Higgins opinion on what is legal or not. My Progresive Suspension shocks are 14.25" long. They have an ajustable dampening rate dial and I get them from Charlie at CR Vintage Racing (760) 451-0056. I don't remember the model number, but Charlie will. Happy New Year!!!

Teddy

 

[tlanders]

More than likely AHRMA will defer to Barry Higgins opinion on what is legal or not. My Progresive Suspension shocks are 14.25" long. They have an ajustable dampening rate dial and I get them from Charlie at CR Vintage Racing (760) 451-0056. I don't remember the model number, but Charlie will. Happy New Year!!!

Teddy