KTM covers "camshaft" issues on 790 and 890 twin engines.

In KTM and other motorcycle forums on the internet, one reads about issues many KTM owners have with the camshaft on engines of the LC8c platform. There are dedicated Facebook groups, some with nearly 10,000 members, and even under our videos, we frequently read comments where (former) KTM riders express their grievances, to put it politely. But what is the truth behind the problems with this engine? KTM has remained silent for a long time, but now there is an official statement.

The engines in question are 790 engines, which were installed in the 790 Duke and 790 Adventure models in Austria between 2018 and 2020, and occasionally 890 engines that were used in the 890 Duke R in 2020. Initially, it was thought that a small number of these engines exhibited an issue with excessive wear on the camshafts.

After extensive research, KTM found that the core issue was not the camshaft itself, but the rocker arms. These were designed too narrowly in earlier models before 2021, leading to increased wear. Starting in 2021, a wider version of the rocker arms was introduced to improve durability. Additionally, a new DLC coating (Diamond-Like Carbon) was applied to better protect the components from wear. Although the discussion often centered around the camshaft, it was shown in 99% of cases that the discoloration of the camshaft had no impact on functionality.

In addition to the wider rocker arms and improved coating, further modifications have been made to enhance the durability of the LC8c engines. For instance, the shaft seal was replaced because the original supplier had received an inadequate specification, resulting in insufficient sealing in some cases. The cylinder head gasket was also revised: instead of the old half-moon shape, a trapezoidal shape is now used, providing significantly better sealing.

Another issue, which occurred rarely, concerned the oil supply to the cylinder head. Residues from the production process were found in the oil channels, which could lead to a lack of lubrication and eventually excessive wear. To address this, KTM has installed an additional unit for cleaning the oil channels.

Affected are the

• 790 Duke models from the years 2018 to 2020
• 790 Adventure models from the years 2019 to 2020
• a few 890 Duke R models from the year 2020

It is important to emphasize that none of the affected motorcycles are from Chinese production, as the relocation of the production of these engines to China only took place in 2023. Of the approximately 55,000 motorcycles of this model series sold worldwide, about 250 machines are affected by this issue, which corresponds to a share of about 0.5%.

Riders of a KTM model from the specified production period should watch out for the following symptoms:

• Loss of power in the low RPM range
• Issues with starting the engine
• Unusual noises from the engine or cylinder head

If one or more of these signs occur, it is strongly recommended to contact the nearest KTM dealer. They can inspect the bike for potential damage to the camshafts and rocker arms and perform necessary repairs. If you are riding a model from the affected years but none of the symptoms appear, according to KTM, you can continue riding without concern.

KTM is committed to repairing all affected motorcycles on a goodwill basis, even if they are no longer under warranty. The only requirement is a verifiable service history. KTM is generous in this regard: customers who have not had all their maintenance done at an authorized dealer will also receive support, as long as they can provide corresponding evidence for external maintenance. The dealer checks the motorcycle for possible signs of the problem and replaces the affected components if necessary, such as the cylinder head, camshaft, and rocker arms. For customers who have already paid for repairs out of pocket, KTM will cover the costs retroactively.