The Montesa Cota 4RT has been in the catalogue since 2005, with the particularity of being equipped with a four-stroke engine manufactured by HRC. In this tutorial we explain how to change the oil on a Montesa Cota 4RT.
The 4RT’s engine clocked at 250cc from 2005 to 2013 inclusive. From 2014 to the 260cc cubic mechanics. And since 2016, there is the Cota 300RR variant (Cota 301RR since 2020). In all cases, the engine block does not change for the purposes of the oil change operation.
HOW OFTEN DO YOU CHANGE THE OIL AT THE 4RT LEVEL?
Oil changes should be marked according to the intensity of use, taking as a reference that with regular weekend use we should make at least two changes a year.
This range of dates will be shorter if we have subjected the bike to some more demanding circumstance, such as a long race, extreme weather conditions or if we are used to riding at a high level.
WHAT SHOULD I KEEP IN MIND?
First of all, unlike any 2-stroke trial bike, you should know that the Montesa Cota 4RT uses two different types of oils.
The first oil, which is housed in the right crankcase, is the clutch and transmission oil. To do this, we recommend the
Repsol Transmission trial 75W
, which is also valid for any two-stroke motorcycle.
The second oil, housed in the left crankcase, is the engine oil. In this case, the recommended oil is
the Repsol Racing 10w40
. Most commonly, when we change this engine oil, we also replace the oil filter and, consequently, the engine gasket, as it will probably deteriorate when removing the side cover.
WHAT DO I NEED FOR AN OIL CHANGE?
Complete oil change kit for Montesa Cota 4RT (49,9 €)
You can also purchase it separately:
Engine gasket for Montesa Cota 4RT
Oil filter for Montesa Cota 4RT
Repsol 10w40 Motorcycle Oil
Repsol Transmission Trial Oil 75W
1 litre cylinder for oil changes.
TRANSMISSION OIL CHANGE PROCESS
1.- First of all we will start the motorcycle and let it warm up for about 3 – 5 minutes, so that when it reaches temperature, the oil is more liquid and we make sure that when we release the screw of the crankcase as much oil as possible comes out,
2.- Continuing with the previous point, we will start on the clutch side. There is no need to disassemble any lids here. We will simply find a 10 metric screw at the bottom of the opposite side (where the ignition is), which when released will start to draw the oil out of the transmission. We will lay the motorcycle on a container that favors the extraction of the oil.
3.- Once the transmission oil has been released, we proceed to place the drain screw and open the upper cap of the clutch cover to pour in the new oil.
Amount of clutch oil in the Montesa Cota 4RT: 0.54 litres (0.57 litres if the lid is removed)
To pour the new oil, we will use the
test tube
, where we have previously placed the exact amount of oil.
ENGINE OIL CHANGE PROCESS
On the engine side, the operation is more laborious, but only if we need to replace the oil filter.
Amounts of engine oil in the Montesa Cota 4RT: 0.41 litres (if we only change the oil), 0.44 litres (if we also replace the oil filter) and 0.60 litres if we completely remove the cover.
The first scenario is the simplest, as you only have to repeat the operation on the right side (clutch), but this time inserting the
Repsol 10w40 oil
. First of all, regardless of the operation, we will release the engine oil through the drain screw.
If we are going to change the oil filter (located where the red circle is), we have to disassemble all the metric 8 screws on the left side cover. Once released, we will have access to the oil filter. We must pay close attention to its position for the placement of the new filter. It is recommended that this filter also has the new O-rings. In any case, be careful not to place the filter without O-rings.
Once we have the oil filter replaced, we proceed to carefully remove the old gasket from the engine cover. Once cleaned, we will place the new gasket and then place the lid. The tightening of the lid is always advisable to do it in a cross.
Once the cover is in place, the filter has been replaced and the gasket has been replaced, we proceed to fill the engine oil following the amounts mentioned above.
With this operation ready, we will have changed the engine oil and clutch of the Montesa Cota 4RT.
Here you will find all the spare parts and accessories for the maintenance of the Montesa Cota 4RT
