Posts
130
Joined
11/9/2016
Location
Hawley, PA
US
Edited Date/Time
5/2/2018 1:56pm
Came across this 1992 KTM 125SX. First KTM for me. Looks like a cool bike. Dyno Port pipe, aluminum subframe. Brembo master cylinder. Bottom end was not assembled correctly im told... Its too tight. The bearings, seals and crank was rebuilt, but i was told that whoever did the connecting rod used shims? Anyway im gonna open it up, see whats going on in there. Does anybody know of any good ktm resources/info for Ktms of this generation? Cheers...☺
The Shop
Just off looks I think it’s an 87 or 88.
87-90 are similar packages and 91-97 are similar (plastic changed in 93 but tank didn’t and everything is interchangeable.)
92 was the first year for the 2 part removable clutch cover and you don’t have that.
Pro-X connecting rod dimensions
Pit Row
If this is the problem what rod / rods can i use or can the 91 prox rod be shaved down on each side? Thanks!
Otherwise, I would start tearing it down and taking some measurements with a caliper. I would measure the case opening, then the total crank width, big end rod width, and go from there. Heck, maybe it is the right rod, and it just seized up on the guy that you bought it from.
No problem for the link - Pro-x has the thrust washer measurements on there site too.
I did a quick search for '87 KTM 125 connecting rod' and wasn't coming up with much either. You could also try www.ktmtalk.com - they have a 2 stroke section that you can ask questions like this also. There are probably some people on that site that know a little about the older KTM's too.
I’m using that Prox rod in mine. I used the Prox piston too for awhile and then found an oem ktm piston on eBay cheap.
http://dirtypart.com/manuals/filer/ktm/KTM%20125-87%20Motor.PDF
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