The Duke forum received a report, complete with photos, from the German Duke forum showing a set of Duke steering head bearings that were alarmingly deteriorated by rust after 2 years of operation in Germany's damp, misty climate. Apparently, the bearings, from a 2013 Bajaj-made Duke, were greased minimally -if at all - during factory assembly.
Shortly thereafter, one of the Duke forum members decided to replace his steering head bearings after a severe impact which destroyed his front wheel. He searched in vain for tapered replacements that would fit, and was told by KTM that it would be impossible to substitute tapered bearings for the OEM units. So he purchased a set of replacement OEM bearings from KTM and was pleasantly surprised at the modest cost of around $30. The good news is that the replacement bearings are not only inexpensive, but relatively easy to replace. Best of all, you can GREASE them copiously before assembly.
Sorry about questioning, anyone on the internet can say anything. Wanted to have the sources checked before ordering and putting in the labor to find out they don't fit. I think I missed the posting about figuring out what bearings work.
So by that logic OEM Ninja 300 bearings should work? Just checked, Ninja 250 and 300 use ball bearings not tapered.
I don't know about ninja bearings.Almost every bike comes with ball bearings for the steering head as stock. You need to have the proper inner and outer diameter as well as height. Tapered are usually aftermarket. If you're going through the effort to replace bearings why not use tapered?
I would not use the ball bearing OEM Ninja setup, I was just thinking there might be a chance the Ninja used a taper bearing that might be of good quality. All Balls is not always of the highest quality but they are probably better than the Indian bearings we get with the bike.