250 Air Boxes

[Chrisbo]

Hi Guys,

Can you get new reproduction Air boxes for a 78 KTM 250 anywhere, or failing that will a later 79/80 one fit a 78 bike?

Thanks
Chris.

[454MRW]

If it's a MC5, then it is a one year only airbox and the later 79-81 250 airbox which looks somwhat similar, will not fit. Tony Friedel had one for my bike and Gary Ellis found one for my brothers and he may know where there is another one a friend has. There is a post with pictures of the first design 78 MC5 airbox on the 4th page of wanted/for sale topics under "wanted '78 MC5 airbox" I hope this helps. Mike

Michael R. Winter
1974 250 Harescrambler
1975 250 HS Project
1977 250 MC5 Project
1978 250 MX6  
1979 250 KTM Project
1980 250 MX KTM

[Chrisbo]

Thanks for that Mike

Chris.

[tlanders]

Of all the Penton/KTM airboxes, this is the one I do not like the most. It takes too long to get the filter out for cleaning. I need to come up with a couple clips or something to get rid of the two little nuts that are hard to get at. Having to take off the side panel also slows down the job because it's nuts are hard to reach with a wrench. The MC80s were a welcome relief to the aggravation of the '78MC5. However, that said, I LOVE to ride my MC5, it is a great bike otherwise.

Teddy

[Chrisbo]

It won't be much of a problem for me Teddy as mine is missing

Cheers
Chris.

[454MRW]

Teddy,
I don't understand what is hard about removing the air filter or side panel. The side panel is held on by only 2 large head flat head screws just like the 3 screws on the 76-77 MC5 panels and the nuts are welded on to the back side of the mounting tabs, unless your are broken off, and the filter is held in place with a pivoting oval shaped wire clamp arrangement which is held tight on the airfilter in the airbox I have with a quick detachable cotter type pin that allows very quick and easy removal from the side. This is the 2nd design I believe and my brother bought an early Acerbis unit that has the lock rod and clamping arrangement that goes in from the top like the 79-81 250 type. It is harder to remove and install the filter.

Michael R. Winter
1974 250 Harescrambler
1975 250 HS Project
1977 250 MC5 Project
1978 250 MX6  
1979 250 KTM Project
1980 250 MX KTM

[Gary Roach]

Michael,
  Tell me if I'm wrong, but I think you and Teddy are talking about two different airboxes. I have two '78 models with both of these boxes. The one Teddy is talking about is the stock airbox that has the air inlet directly under the seat and uses the same air filter as the '72-'75 Pentons. Just like Teddy descibed, the cage is held in by two little 4 or 5mm nuts on the front side of the airbox making it a real pain to service the air filter. The one you are decribing sounds like the nice replacement airbox made by HiPoint (look for the HiPoint name casted into the plastic on the left side above the lid). The air inlet is on the back side of the airbox, just in front of the inner fender, and it has a different shape air filter.

Gary

[454MRW]

I do have the Hi-Point airbox as does my brother NOW for our 1978 MC5 250's, but my brother had at first and still has a NOS Acerbis opaque 1978 MC5 airbox that takes the oval filter like the 72-75 and 79-81 Penton/KTM 250's and utilizes the same clamping arrangement used in the 1979-81 250 air boxes, (a plastic "Z" shaped reatiner held in place with a metal rod that goes through the hole in the bottom of the airbox and is held in place at the top by a metal "U" shaped tab bolted to the side of the upper portion of the airbox) and provides tension on the rod against the piece that clamps the filter in place with the cage. Since the airbox is open on the side also, that filter arrangement may allow removal from the side unlike the 1979-81 version that is removed through the top of the airbox, but may require removal of the seat to disengage and remove the lock rod. I take it that there is a third version of the airbox? If I were Teddy, or anyone with that particular 1978 MC5 airbox setup, I would switch to the Hi-Point airbox as it is much much more user friendly than either of the other designs! The side panel and filter can be removed in less than a minute without removing the seat.
It also sounds like Teddy's side panel frame tabs are missing the welded nuts. Most auto part stores sell clip nuts that would slip onto the frame tabs and be compatible with the Metric side panel screws.  

Michael R. Winter
1974 250 Harescrambler
1975 250 HS Project
1977 250 MC5 Project
1978 250 MX6  
1979 250 KTM Project
1980 250 MX KTM

[tlanders]

You are right Gary. Thanks for the ideas Michael. When I get back to playing with the MC5, I'll make the side panel mods. Does anyone have the newer style airbox for it? Oh, that is how this thread started!!!

Teddy

[Chrisbo]

Eye, So does anybody know if you can buy new airboxes for a 78 KTM 250 [?] [?]

Chris.