76 KTM Penton 250 rebuild questions

[Slakewell]

The rear frame loop were the shocks mount are the smaller tubing / not the GP frame that came out late 74 till late 76

[Chuckie25]

I made a little video showing the chassis

[ozktm]

Read below about differences. Note Cross Country model used the 74-76 GP frame that slakewell refers too.

1976
* Model line diverged into two distinctly different models - the MC5 and the Cross Country
* 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

1976 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

1977
* First year for GS6 model (GS means Gelande Sport and Gelande means terrains ) and 6 means 6 speed)

1977 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

[oz555ktm]

  The bike is 1976/7 250cc  if its got only 3 bars under the tank is a 77 if its all coverd its the High breather 1976 ...

   Need a Fram number and a engine Number and all the gesting is then over !!!!!!!!!!!!!!!!

[Chuckie25]

OOPS!! Forgot to post the link to the video 

This one shows the engine
http://www.youtube.com/watch?v=-e1du9OYI8E&feature=youtube_gdata_player

This one shows the frame
http://www.youtube.com/watch?v=y2vHQki8O64&feature=youtube_gdata_player

[Chuckie25]

The clock on the case shows it was manufactured December of '76

[supermotomc]

so whats the frame number

[ozktm]

This sticker that is on the side covers throws a hint at 77

, plus the late 76 engine date, and the tank decal on the bike is the 77 version.

Makes no difference as the 76 and 77 mc5 as per my previous post are basically the same.

Looks like a major task to bring this one back from the dead, but i assure you it will be worth ir when you throw your leg over it.

Contact Al Beuhner (details on Penton site www.pentonusa.org ) he will assist in any parts you need to get it going.
Might be worth your while looking for another engine - a couple are on ebay. Any from 76 to 79 will do fit. This way you won't have to attempt to repair the magnesium cases.

Adrian

[Chuckie25]

This sticker that is on the side covers throws a hint at 77

, plus the late 76 engine date, and the tank decal on the bike is the 77 version.

Makes no difference as the 76 and 77 mc5 as per my previous post are basically the same.

Looks like a major task to bring this one back from the dead, but i assure you it will be worth ir when you throw your leg over it.

Contact Al Beuhner (details on Penton site www.pentonusa.org ) he will assist in any parts you need to get it going.
Might be worth your while looking for another engine - a couple are on ebay. Any from 76 to 79 will do fit. This way you won't have to attempt to repair the magnesium cases.

Adrian

Thank you! As soon as I get the bike in my possession I'll get the frame numbers. And I've found everything I need on Mr. Beuhner's website besides the engine bearings. It says sold out or out of stock nect to them. And I was planning on finding a set of cases and just replace mine. If I could afford to buy a complete engine I would but I want to put my jug and head on what ever engine I use (wether it be new cases for mine or find another engine and swap the top end) because mine is ported. It's etched M.L. 4 - '80 on the bottom of the cyl. So, just gotta find cases, bearings and buy a gasket kit. Oh, and I need a carb for it. From what I'be read they came with either a Mikuni, Bing or Lectron. Was thinking of finding a stock Quadzilla carb for my LT250R and putting the stock TM38 off the LT on the KTM.

[Slakewell]

36 Bing works best on them IMO but you have to how to file the file the slide to get them right.

[Chuckie25]

few questions:

what are the color codes for the cases? both the blue and white/silver


ppusa is sold out of the engine bearings, soooo what are the bearing numbers? my mom can get me bearings really cheap from her job so ill just get them that way.


how easily repaired are the fuel tanks? or can they be repaired?

seat foam is EXPENSIVE, could i just get some foam and cut my own (id need measurements if someone would be so kind as to take them for me )

and what is the brake rod length? mine is rusted in half and the onl ones on the pentonpartsusa website are for 175cc bikes 

lastly,

i need a manual. wheres the easiest/cheapest place to find one? (oz555, idk what it would be to send the rebuild book to the other side of the world and it wouldnt do to tie your book up over seas ya know?)


thanks kilos yall im slowly but surely getting stuff ready to start on this thing lol. so far got my stator and clutch cover sanded down and ready for paint and decided that im going to repace  the rod and big end pin/rebuild the crank

[ozktm]

Color codes can be found on the Penton Site. Do a search on their forum, i found them on there, from spray pack to car codes that suit.

Bearings, i am sure Al Beuhner can help you over there, but we are running the flat roller versions over here. Which are available and cheaper.

I the tank is fibreglass then yes you can repair, or pass onto a boat repairer or similar to fix for you if you unable to complete it satisfactorily, otherwise there are a couple of Brand new plastic ones available on Ebay for about US$140.

Brake rod's - maybe ebay - or place a post on the Penton forum for some help.

Seat foam - the 74 long seat foam's on ebay will fit. About US$64, which i consider a good price.

Manuals - Al Beuhner has these available over your way, only other way is if we scan in a set. I do have the engine rebuild scanned in, but would have to scan in the Chassis and Engine Parts books.

The Penton Forum is probably your best chance for some help being that you are over that way. There may be some penton gurus nearby that would no doubt come and help you out if you needed it.


Regards,