Frame numbers

[kds449]

I have this Penton frame and dont know what year or model it is. Could use some help. Serial number is 550 05600.

[Steve Minor]

I say it's a 1976 MC5....anyone else?

Check the "Production Years" from the Home Page.

Steve Minor
Wilmington, NC

[454MRW]

The closest frame # I have is 6132, which is a 77 dual position footpeg MC5 frame. I have previously owned some more 76 frames, but none verified above around serial # 3000. I would assume that it is a 1977, but once the late 76 with the angled rear seat rails started, late 76 and 77 without the dual position footpeg frames are the same. If you have the original tank, the decals would be the identifying markings. There is not a lot of documentation about when they changed from 76 to 77, since the frame serial numbers ran consecutively through both years. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
75 Can Am 175 TNT & 77 250 Black Widow
1976-78 RM & 77-79 PE Suzuki's
74 CR250M 07 CR125R & CR150R

[Steve Minor]

Mike....there's no question that you have WAY more knowledge about Pentons than I do. I went to the "Production Years" on the home page and saw that frame serial numbers beginning with 550-xxxx were considered 76 models? Did I miss something? Please educate me. Here's what the Production Page shows.

--------------------------------------------------------------------

1976
* Model line diverged into two distinctly different models - the MC5 and the Cross Country
* December 1975 brought the debut of the new 125cc KTM engine with 32mm Bing carburetor
* 125cc engine has black cylinder and head fins with "125 KTM" cast in side of cylinder  with silver gear box - all other
   engine sizes are totally finished in silver

MC5
* Starting serial number is 55000000 (MC5's only)
* First year for MC5 (MC means motocross and 5 means 5 speed through many are found as 6 speed)
* MC5 model came in 125cc, 175cc, 250cc and 400cc sizes
* New non-breather frame and swing arm with magnesium air box
* Marzocchi shocks mounted at 45 degree position with no other adjustment postions
* Motocross seat with integrated rear fender
* Leading axle Marzocchi or Ceriani forks
* Sun rims
* New 2.1 gallon gas tank
* Finish is orange with yellow number plates
* MC5 gas tank decal was a long wide black and white stripe with the word "Penton" in white
* West Coast KTM bikes were mostly red and a few of the very first MC5 400's were white; European models were blue



Steve Minor
Wilmington, NC

[454MRW]

Steve,
They did not change the MC5 550- frame numbers in 77, they just continued them through both years. The only difference was the 77 GS-6 which went to the 701 and so on frame number.
Unfortunately since the MC5 550- frame numbers were the same and just accumulated during the production of 76 and 77 models, there is no record of when it stopped being a 1976 and started the 1977 models. Like I said earlier, I have not seen any actual 1976 model MC5 with a serial number under 3000, and maybe even lower. I tried to get the production numbers after Kalman spoke at the AMA Museum meeting, but it never materialized, and the information about production figures in Kips KTM book was confuzing at best, since it only contained combined data from all of their production, not just certain models.

1977
* First year for GS6 model (GS means Gelande Sport and Gelande means terrains ) and 6 means 6 speed) MC5
* MC5 same as 1976 except new black with white trimmed C-shaped decal around the word "Penton" which was in black
* Frames had a slight but noticable modification on some brackets as compared to the 1976 where the rear of the seat bolts on
* Some frames had the option to mount the foot pegs in two different height settings
* Exhaust pipe had an extra strengthening gusset on top where the silencer is welded on to the pipe

Generally it is considered that when they changed the rear frame rails is the point at where they are 1977 models, but there are a lot of bikes out there with the older 76 decals and the 77 style rear frame rails and 6-xxxxx engines, so this is not a definite way of determining whether the bike is a 76 or 77. I sold one recently at Mid Ohio that originally had the older style decals on the tank and had the newer style frame rail and a 6-54 engine and considered by me to be a late 76 model. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
75 Can Am 175 TNT & 77 250 Black Widow
1976-78 RM & 77-79 PE Suzuki's
74 CR250M 07 CR125R & CR150R

[tomale]

what is this about the angled seat rails? my Mc 5 has a
frame # 026** and the 77 with a 060** and the seat rails look the same to me.

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

[454MRW]

On the early 76/77 MC5 frames, at the very rear portion of the frame, the seat bolts to a flat plate. On the later production frames, the rear of the frame forms more of a 3 sided rectangle and is substantially stronger. Mike
Here is a later version pic of the MC5 rear frame rail. I don't currently have an early frame to post a pic.

Although this is not clearly shown, here is the 76 rear plate. It is only a flat plate that does not wrap around like the later version.

**Thom, this just points out that the frame rails changed in late 76, not at 77 like as suggested in the production year guide because of the lack of documentation. I wish that we could update the list with known frame numbers tied to known model year bikes, so it could be clarified better. Mike
Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
75 Can Am 175 TNT & 77 250 Black Widow
1976-78 RM & 77-79 PE Suzuki's
74 CR250M 07 CR125R & CR150R

[kds449]

My frame looks like the one in the picture.

[454MRW]

KDS449,
I added an early 76 frame pic. If yours is like the top pic, then I would say almost certainly, due to the higher serial number and the rear seat mount plate design, you have a 1977 MC5 frame. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
75 Can Am 175 TNT & 77 250 Black Widow
1976-78 RM & 77-79 PE Suzuki's
74 CR250M 07 CR125R & CR150R

[kds449]

454mrw
It looks like the top one, thanks alot. How would you know if its for a 250 or a 400 or doesnt it matter.

[454MRW]

250 and 400 frames are the same, but 125/175 frames have a mid mounted exhaust pipe mount bracket that is located near the Right Hand shock mount beside where the airbox sets. The 250/400 frame has a rear mounted exhaust pipe bracket located on the Right Hand side of the frame at the rear, near the seat mount bolt hole.
I have a 250 engine currently mounted in a 175 frame, but the stock 250 shrouded pipe won't fit with the 175 pipe bracket in the way. I used a 1981 250 pipe to clear the bracket with a removeable silencer. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
75 Can Am 175 TNT & 77 250 Black Widow
1976-78 RM & 77-79 PE Suzuki's
74 CR250M 07 CR125R & CR150R

[tomale]

I did not know that, yea my 76 is just like the one in the upper picture, there were so few I had to ordered mine, the first MC5 I ever saw was in april of 76, it was at that point I started thinking about a KTM, it took me several months to find a dealer to even get one for me..it was not until oct. of that year that I finally got mine, I always thought I had seen a  pre release model but I guess I did not, there were just not very many of them in the bay area. The funny thing is that now the availabilty of parts is 1000% better than it was back in the day, I can remember spending alot of time trying to find out what the deck height was, I had no way of knowing or measuring and so I just replaced the gaskets measuring the old and then trying to match it with new ones.. No one had a manual for my bike and know one even knew it they were available or where to even look...I race it alot back then and I had only seen one other bike like mine until early 77.

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

[454MRW]

Well,
I'm off to Texas for Thanksgiving with my Niece & Nephew-In-Law and their new home in Cuero TX. I will check when I get back home Sunday for any questions. Have a happy Thanksgiving! Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
75 Can Am 175 TNT & 77 250 Black Widow
1976-78 RM & 77-79 PE Suzuki's
74 CR250M 07 CR125R & CR150R

[kds449]

Thanks for your help and have a Happy Thanksgiving and a safe trip, Keith

[xracer]

have a save trip and dont forget to pick up my new bike thanks dave  when doubt gas it