Cross Training Adventure

Causes, symptoms and preventive tips for camshaft wear and failure on KTM 790, 890 and Husqvarna 701s. Welcome to Cross Training Adventure, we are into all things dual sport and adventure on the east coast of Australia. The dreaded camshaft failures on motorbikes using the LC8c engine. Their are multiple potential causes. Let's start with the most likely ones. In 2020 KTM realised that their cylinder heads were not being cleaned properly. The affected models? KTM 790 and KTM 890 Duke and adventure models. And the Husqvarna 901. It's a complex issue. There's a lot of debate. Not every LC8c model will be affected. It is why KTM introduced a small oil screen filter in 2020. However, many have argued this was an inappropriate solution as another problem with the LC8c engine design is poor oil pressure. An oil filter in a narrow passage only makes this worse. We do know KTM only publicly acknowledged the problems after six years of complaints and pressure from owners. We've collected information from mechanics, owners and industry insiders to establish the causes, potential solutions, KTM's very poor track record, and whether it's safe to buy any model with an LC8c engine. Keen on adventure riding in Australia? Check out our vids. Some owners believe Motorex 10W-50 is not a great oil, or the wrong type is recommended. For example, some riders change to 10W-60, hoping the slightly thicker oil will maintain that critical oil film strength when the aggressive LC8c engine runs hot. Whether this makes a difference is debateable. Casting material was allowed to circulate through the engine and cause premature wear and failure. What is critical here is that there are documented cases of KTM denying warranty claims on failed camshafts due to dust in the engine, despite this occurring due to the poor air intake system. Engine oil. But experts agree it is not an actual cause. This was a very likely cause for pre-2020 models, especially when camshaft wear was detected at less than 10,000km. This leads to another likely cause. Poor oil pressure and oil supply to the top end. Mechanics who have stripped down the LC8c engine have found multiple reasons for poor oil pressure. The cross drilled oil ways have been poorly aligned in some engines which restricts oil flow. The oil gallery is very small and can contribute to this. Check out our reviews of various adventure bikes and dual sport bikes. Some mechanics say the 0.5 mm diameter of the oil jet orifice is too small and too easily blocked by debris. Next? Another potential problem is the heavy concentrated load between the camshaft lobes and finger followers. This is known as Hertzian Contact Stress. This load is increased with the aggressive camshaft profiles which KTM uses. A mechanical engineer tested the hardness of the camshafts and found them to be too soft although KTM claims their testing shows they meet their requirements. Earlier KTMs used very narrow 6mm followers. Metal fatigue allowed the DLC coating to crack, allowing flakes to prematurely wear the cams. In 2021, KTM began using wider 8mm finger followers. If you like dual sport riding in Australia then you might like our adventure riding vids. However, there are cases of finger followers completely breaking due to metal fatigue and causing catastrophic failure of the entire engine. Some owners claim KTM will not admit to this publicly because it will legally require them to have to call a recall. In 2021 KTM also began using a DLC coating, a Diamond-Like Carbon coating. But some owners have said this only contributes to the problem. If other issues prematurely wear the camshafts then that DLC coating allows incredibly hard bits of debris to circulate through the engine. Next? Dust ingress. Buying a used 790 or 890? Quite a few owners have had multiple failures. You might be buying a KTM that has been fixed but it may just fail again. Some owners say the risk is worth it. Others are so annoyed after the first failure then swear off KTM completely. KTM's air intake system has had a lot of issues with paper filters on earlier models. ================================== INDEX 0:49 Possible causes 5:37 Preventive tips 7:31 Warning signs 8:33 Chance of cam failure? 9:31 Can we trust KTM warranty? 13:39 Chinese models affected? 14:07 Should you buy one? ================================== CREATIVE COMMONS VIDEOS USED Many thanks to these Youtubers for allowing use of their vids under the Creative Commons Licence. https://creativecommons.org/ KTM 790 Adventure Review The Perfect Middleweight Adventure https://www.youtube.com/watch?v=iMG_bNUw7Eo Trail riding, on my KTM 790 Adventure https://www.youtube.com/watch?v=FjX7SzpSsII&t=419s Faulty engines in KTM 790 / CF Moto 800 / Kove 800 ?? https://www.youtube.com/watch?v=O-HKQhxEDcA&pp=ygUQa3RtIDg5MCBjYW1zaGFmdA%3D%3D #crosstrainingadventure #adventureriding #adventurebikes #dualsportriding #dualsportbikes