KTM Motor Mounts

[Chakka]

I started to rebuild my Jackpiner. At closer inspection I noticed the ignition side motor mount under the engine is extremely worn. The hole is elongated and the bracket itself paper thin. Have any Pogers replaced these and can you share any tips with me? I ground the welds and pulled the old worn bracket off the bike so a new one can be fit.
Chakka

[Big Mac]

If it makes you feel any better, the '77 250 GS6 frame had the below-the-engine motor mount, while the '77 400 MC5 (most likely 250 MC5 too) has no motor mount at all under the engine--no tabs on the frame on two I've seen. Doesn't seem to hurt the 400 MC5 which is a vibrating bed in comparison to what a 175 puts out.

That being said, the only ways for the holes to get elongated is for the motor to be loose at all mounts and would guess all are elongated. Saw one that way and was able to weld-fill the frame tabs as well as the rear mount steel insert, then redrill-- tightened things up just fine. Mac

[454MRW]

My Project 77 MC5 250 frame does not have the mounts under the engine either, but my 1978 MC5 has them as well as the hanging upper support braces, and my 1979 250 and 1980 250 frames have them, but KTM did away with the hanging upper support braces as well in 1979 and 1980 frames.

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

[Chakka]

Wow, no frame supports under the engine? This frame is a 1975, I need to check the 77' frame I have when I get home and see if it was something that got phased out. So your motors are bolted at the front and rear along with the aluminum support struts and that's it? I probably should have left my old worn bracket in place

Chakka

[454MRW]

Both my 1974 and 1975 250 Harescrambler frames have both the mounts under the engine and the upper support brackets. I wonder if they only left them off for one year (77 MC5) and determined that they were very beneficial and KTM decided to add them back in 1978.

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

[Chakka]

I checked my frame collection today and both 75' frames have the under engine brackets. My 77'GS frame does not. I think your right Mike. They probably tried not using them one year and since they reappeared on the 78's that indicates to me they serve a purpose.
Chris  

[Big Mac]

Yes, I got that backward, my '77 GS6 is the one without the lower bracket, the MC5 does have it. Failing memory. Thought it strange when I discovered, but doesn't seem to have made a difference so far. I'd guess the upper struts and lower motor mounts would serve to stiffen the rigidity of the frame from twist and torque.