Let’s say you’ve been riding your bike for a while. Now you want to try out different things with your bike.
Or you are simply willing to know whether you can improve the performance of your bike.
Hence, you want to know if you can use a Shimano 10-speed derailleur with a 9-speed shifter.
If you are using a Shimano Road bike, then the 10-speed derailleur will work with a 9-speed shifter. But if you are using a Shimano Mountain bike (MTB) it will not be as efficient. Because the rear-shift ratio will not match in the case of the MTB. Besides, you also need compatible components.
We’ve elaborated on these issues in the entire article. Do stick with us till the end. We’re certain that it’ll help you.
So, let’s dive in.
Firstly you need to consider which type of bike you’re using. The gear shifting system is different for the mountain bikes (MTB) and the road bikes.
Then you should consider the compatibility. You need to attach the components of the same brand.
For better compatibility, you must use Shimano for both the derailleur and the shifter.
You should also consider that the quality and the condition of the component also matter. In this article, we will mostly reflect on the perspective of best quality products. Such as the best Shimano 10-speed derailleur and the best Shimano 9-speed shifter.
Because a bad quality component even if it’s compatible will not yield an ideal performance. It will show various problems. Such as the movement problem of the front derailleur.
After that, you also need a proper rear shift ratio between the shifter and the derailleur.
Remember that Shimano provides a vast range of shifters and derailleurs. Each model is engineered with precision to match its stock components.
So, using a different range of components may not yield the optimum performance outcome.
Shimano 10-Speed Derailleur With 9-Speed Shifter Compatibility
Now let’s analyze whether the Shimano 10-Speed derailleur is compatible with the Shimano 9-speed shifter. We will be focusing on mainly two types of Shimano bikes. The mountain bike (MTB) and the road bike.
For that, we need to take a deeper dive. It’s sort of similar to an 10-speed shifters with 11 speed rear derailleur
Let’s get started.
In simpler words, you cannot use an SRAM component with a Shimano component. For example, you cannot use a Shimano derailleur with an SRAM speed shifter.
Well, some people will suggest that it’s a good idea to interchange components of different brands. But in reality, it’s not.
But you will face some major malfunction at some point. And this could very well be risky for you.
Because of that, it is recommended to use both the derailleur and the shifter of Shimano.
Now you could very well be wanting to know about compatible components with the rear derailleur. For more details have a look at this rear derailleur guide.
How does it work? Well, it’s not that complicated.
Every time you turn the speed shifter the gear cable is pulled and the shifts derailleur. It occurs for both the upward and downward shifts. The movement of the derailleur per 1 mm of the cable pull is known as the rear-shift ratio.
Shimano Road Bikes
When it comes to Shimano road bikes, the rear shift ratio shouldn’t be a problem. The rear-shift ratio of the Shimano 10-speed derailleur is the same as the Shimano 9-speed derailleur.
For this, you do not need any modification of any components.
You can simply attach the shifter with the derailleur with the gear cable. And you’ll be ready to go.
You should keep in mind that this might not be as smooth as using a Shimano 10-speed shifter.
Shimano Mountain Bikes (MTB)
Well, it is a bit tricky when it comes to mountain bikes.
Shimano MTB 10-speed derailleurs cannot be used with the Shimano 9-speed shifter efficiently. Because their rear shift ratio is not the same.
Shimano MTB 10-speed derailleurs feature a rear shift ratio of 1/1.2. This suggests that for every 1 mm of cable movement, the derailleur moves 1.2mm.
On the other hand, Shimano MTB 9-speed derailleurs have a rear shift ratio of 1/1.7. The 9-speed derailleur is designed to move 1.7mm for every 1mm of shifter cable movement.
The cassette of the 10-speed models is narrower than that of the 8 and 9-Speed models. As a result, the Shimano MTB 10-speed derailleurs have a smaller gear ratio.
Let’s say you are using a 10-speed Shimano MTB derailleur with a 9-speed shifter. Now, what’ll happen?
This will result in the derailleur not moving far enough to allow for smooth shifting. Consequently, the shift will either fail or be partial. And the chain will continue to rub against the cogs.
This will eventually give you a very scrappy overall riding experience.
Although some suggest that modifying the rear derailleur could help to overcome the rear shift ratio problem. It’s a very minor and easy modification. If you are up for experimenting then you should go for it.
What you need to do is drill a small hole in the derailleur so that the gear cable can pass through. Then passing the gear cable around that hole fixes the gear ratio.
Friction shifters are kings of compatibility. Although it is not most commonly used in modern-day bikes. But still, they can be seen on the roads now and then.
The main reason for their compatibility is their flexibility in shifting. Compared to friction shifters the indexed shifters are very rigid. Friction shifters move the derailleurs as much as the riders want them to.
This removes the equation of the rear-shift ratio. You can shift as much as you want. And the gear will shift to the very top and the bottom gear. Suiting to your needs.
Here’s our recommendation for best friction shifters out there.
- SunRace MTB Right Friction Shift Lever is compatible with Shimano 10 speed derailleurs. They adjust really well with the derailleurs.
- If you want something extremely easy to install, you can go with the SPORTLIMIT Sunrace SLM10 Friction Shifter Set. They also have excellent compatibility.
However, there is a downside to friction shifters. They are pretty difficult to work with. Especially for the beginners. That’s why most commercial bikes do not use it.
Usually touring cyclists prefer friction shifters. As they are easy and reliable to use.
Here we’ve curated some of the most frequently asked questions for you.
Is it possible to use road shifters with a mountain bike derailleur?
Yes. It’s possible to use road shifters with a mountain bike derailleur but under a few circumstances. Such as the rider needing to use index shifting. Then it can be interchangeable as long as the transmission is up to 9-speed.
Is it possible to use SRAM derailleurs with Shimano shifters?
No, it’s not possible to use SRAM derailleurs with Shimano shifters. The two brands have different systems. To be compatible the cable pull ratio and the shift activation ratio should be the same. SRAM and Shimano have different cable pull and shift activation ratios. Hence they are not compatible.
Which is the best gear for flat roads?
Middle gear is perfect for flat roads. When you are going down a level road, this is terrific gear to put on. It’s important to have some resistance. But not too much resistance. If the route varies in elevation, you will likely shift between the rear gears to handle the changes.
Hopefully, by now, you’re clear on the Shimano 10-speed derailleur with a 9-speed shifter.
Thank you for reading this far. Hope you had a good read. We also hope to see you soon.
Until then, take care.