How to increase the durability of gear-shifters

Question

I am not a professional cyclist and may not even be a good rider but it seems like I tend to break my shifters way too often.

I initially had a SRAM-X4 8x3 Shifters which ripped apart in an accident. This seems reasonable because the accident was the reason the shifter broke.

So, I upgraded to a Shimano ST-EF50 8x3. This is where the problems seem to arise. Once again, I want to humbly point out that I might not be a good rider and might have put some excessive stress on those shifters than they are meant to withstand but from what I've noticed, after just 8 months of regular 2 hours/day commutes, the 8-speed shifter's top plastic part just popped out. I was speculating that maybe I might have dropped it somewhere quite hard and this might have done some damage to it but for what I was concerned due to my tight schedule it was at least working so I took some masking tape and rolled around the shifter to temporarily hold the plastic so that I can go home and fix it. Since I am a student and I couldn't find any time to fix it and unfortunately so I was forced to ride my cycle without permanently fixing the shifter. After a month, the 8-speed shifter completely failed, all the parts inside started to come out. I understood that it could be my fault to use it without fixing so I didn't think it was the shifter fault.

This model was the standard shifters found in most entry-level cycles so I assumed it would be reliable so I bought another set of the same shifters and to my surprise, the same issue came again after 10 months but this time in both shifters. This time I just bypassed the shifter and kept my 8-speed derailleur in 4th and was riding it doing 2-3 hour/day commutes. I skied off the main road after a car bumped into me. The impact was high and my rear derailleur (Shimano Altus RD-M310) broke completely. I basically left my cycle on dirt for 6 months and thought of doing a complete 8 to 9-speed upgrade.

I bought a brand new Shimano Alivio RD-M4000 and SL-M4000-R and L shifters. I kept the old stock front derailer Shimano Altus FD-M310. Everything was going smooth, I really enjoyed riding my cycle. It felt brand new. I enjoyed it so much that I took it for 8 hour/8-10 km drives 3 days once and that was the end of the happiness. 1 year later, it happened again. The shifters broke but this time only the left 3-speed one. Right now I am convinced that there's something in my driving style causing the damage. I don't know what is causing the damage but what I do know is there is something which is causing the damage. After some conversations with my biking community, it seems like it is common for gear shifters to fail and I want to know if this is true. My objective is to use your amazing expertise to advise noob cyclist such as myself on how to use the gear shifters and to find the answers to the following questions.

• Will the way we're using the shifters affects its durability?
• If so then how to prevent it?
• Are there more durable shifters in the market then mentioned above?
• Are there any other miscellaneous advice regarding gear shifter you'd like to provide for the new and upcoming cycling enthusiasts?

Thank you so much for your valuable time.

PS: I'd like to point out that all the parts mentioned above were bought in an authorized showroom. The cycle was bought from Decathlon and is a Rockrider 5.2.

Initially, it was shipped with a SRAM X-4 8-speed and now after many upgrades, it has a Shimano Alivio RD-M4000 9-speed as mentioned previously. I do know it's expensive to upgrade each part rather than buy a new cycle with the better parts. The sole reason I am sticking to this cycle is for sentimental purposes.

Answer 1

There are many reasons for bicycle components to fail:

• A design fault
• Cheap materials (which is common in cheaper shifters)
• Mistreatment

The Shimano EF50 is a low grade brifter and not intended for heavy use. Despite that it's 'ok', and could last years.

However your post indicates 'abuse'.

Running a bicycle in the same gear for months will wear out that cog and is indicative of neglect of other parts.

Anyway, Shimano sells things in 'groupsets'. Mostly this is marketing. But generally more expensive 'groupsets' are higher quality. They don't give details on how this breaks down because they want you to upgrade all components (shifters, derailleurs, cranks) when perhaps you don't need a more expensive crank (which may only be lighter, not necessarily shifting better or being more durable)

So in many cases they may sell the same shifter with two different labels on it whereas in fact these parts are identical, or identical except that one is 8 speed and one 9 speed.

So you may be wasting money by buying 'Alivio' rather than 'Altus'. It's as well to look at the specs, examine the components in hand , etc.

The specs are online https://productinfo.shimano.com/download/pdf/spec/3.1/en

For older components you might need to look in the archive

https://productinfo.shimano.com/#/archive

For the sl-m4000 the specs are

• Shifting lever bracket aluminium
• Clamp bolt stainless steel
• Lever body resin & steel
• Base cover resin
• Shift cable - stainless (this is just the supplied cable, which should be changed maybe annually)
• 2-way release

Whereas

Sl-m3000 (Acera)

• No 2-way release
• Shift cable is steel (option for stainless)

Sl-m2000 (Altus)

• Clamp bolt is not stainless

So largely the three shifters are the same quality, but the m4000 has the 2-way release feature, and the Altus has more bits that might rust.

Looking at the sl-m590 Deore, then the resin is replaced with GFRP.

That is also plastic, but better plastic. So you didn't necessarily buy a more durable shifter by going Alivio

The SLX level typically offers little to no performance advantage over Deore for shifters and derailleurs, but often there is an extra speed. And the hydraulic brakes are upgraded compared to Deore.

Shimano's most durable stuff is Deore XT. Here the main shifter level is aluminium - no plastic.

Typical wisdom is 'Deore' is the minimum level for hard use. But Shimano have exploited that for the current year, so the new Deore M4100 would previously have been called 'Alivio', and uses all the same cheap plastics as Alivio , Acera and Altus did.

So you can't fully rely on that.

Essentially if you wanted the best shifters possible, you'd fit Deore XT 9 speed shifters. But failing that Deore and SLX 9 speed would be about the same as each other and better than Alivio.

I haven't seen your shifting style, but I'd note that st-ef50 was replaced about 10 years ago with a different part , so not sure if this was a new or used part!?

Also if you go to si.shimano.com then you can download the exploded diagrams for each shifter, find the spare part numbers and so on.

So for example if you had the m4000 shifter failing in a certain way, and you had in mind a given shifter to replace it, it would be a good idea to compare the construction both via the exploded views, and by photographs, to see if they were in fact different designs. As sometimes to shifters with different numbers can be physically very similar.

For the future if your shifter cover has popped off you should immediately repair it.

I have never had a shifter fail, but if you keep your bike in the rain, hit it, store it poorly, etc., that could lead to such an issue.

If you fix issues as soon as they arrive, develop more mechanical sympathy, including learning to fix and repair your bike yourself, then you should find that it lasts much better.

Answer 2

There are a few ways that user habits or mechanical adjustment can negatively effect durability:

• If you downshift the right or upshift the left when the cranks aren't moving, you'll be putting excess force through the internal parts. A little bit of this isn't a big deal, but doing it habitually can break shifters.
• Left shifters sometimes fail prematurely due to a combination of too much cable tension and the front derailleur high limit screw being set in enough that it causes the shifter to be held under tension when in the large chainring position. What happens then is that when shifting into the middle ring position, the release lever push is very hard and excess force is put through the shifter.
• Some people shift more than others. This has an impact on shifter lifespan.
• Shifters need their internal lubrication, and some environments are harder on it than others. Usually this would not explain the kinds of failure you're talking about, but sufficiently rainy/salty environments could prove an exception, especially if the bike is stored outside. Shimano trigger shifters are factory lubricated with a few strategically placed globs of highly washout resistant grease, which can be carefully replenished if things do get dry inside.
• Some cyclists ram the shift levers with arbitrary amounts of force and others have shifting technique that's more calibrated to the fact that there are internal parts sliding past each other inside making it all work. The former will wear out shifters faster. Usually the difference will be fairly minor, but again it's conceivable for more extreme cases to prove an exception.

Shifters get more durable the further up in the product line hierarchies they are. Someone riding as much as you describe is generally speaking going to be the kind of cyclist that benefits from getting mid-range or better components, i.e. Deore. That said, all trigger style shifters could suffer and break from the above conditions, and I'd suspect there's some cause other than putting a lot of use through low-end shifters that's causing the failures.

The highest durability compatible indexing shifters you could get are Shimano SL-BS77 bar-ends mounted to something like Paul Thumbie mounts. The ball detent based indexing they use handles force in a very different manner than pawl type indexing, and they are more inured to some of the above problems. That doesn't mean that going that direction necessarily makes sense given the expense, or is the only solution.