ISM saddles have a completely different design to a traditional saddle, and as a result, they require a completely different set of rules when positioning them on your bike. If you are changing from a traditional saddle to an ISM saddle, this blog should help you achieve the intended position.
Due to the increased height of the rails and different profile on ISM saddles, it is necessary to lower your saddle height to compensate for this. ISM recommend to start by lowering the seat post by 5mm but this can be variable depending on the shape and padding depth of your previous saddle. It is definitely worth checking your knee extension angles using our Bike Fit service to ensure you aren’t over-reaching or under-reaching as this can cause knee injuries to develop.
ISM have essentially removed the ‘nose-area’ of a standard saddle. This means that you should sit much further forward on the ISM saddle than usual.
A lot of measurements we take during a Bike Fit involve measuring from the front tip of the saddle, including when measuring the saddle fore-aft. When setting the ISM saddle, a good starting point would be move the tip of the saddle 5-8cm further away from the bottom bracket. For example, if your Saddle Setback measurement was previously 45mm, this would need to increase to somewhere between 95mm and 125mm depending on the shape and profile of your previous saddle. A bit of trial and error may be required here. It’s not uncommon to require a seat post with extra setback to fit an ISM saddle in the correct position.
The starting point when fitting an ISM saddle (like any other saddle) is to set it horizontal. A common mistake I see when ISM saddles have been fitted, is that the rails of the saddle have been set horizontal, NOT the top of the saddle (the bit you would sit on). The rails of ISM saddles are not parallel to the top surface, therefore make sure you only look at the saddle top when judging the tilt.
If you have an ISM saddle model starting with PS, PM or PR, you will need to look at the very front end of the saddle to judge whether it is horizontal or not. The rest of the saddle will kick up and it often looks as though it is pointing nose down, but the area your pelvis will rest on will actually be horizontal (see picture below).
If you have purchased an ISM saddle and having trouble fitting it to the correct position, please get in touch and see how we can help you.