Shimano Tiagra 4800 - Centre Spline Wear

[Rooster1]

Hello

My tiagra crankset splines have worn down after about 6000 miles, both on the male and female teeth.

There was a bit of play on the bottom bracket and I think this has taken its toll elsewhere.

I've replaced the outer ring but the whole crankset is toast.

Reference photo (not my bike)

Is the wear to be expected at some point in time after 6000 miles ?

 

[I like Skol]

That isn't wear. Nothing wrong with those splines.

 

[Ajax Bay]

That isn't wear. Nothing wrong with those splines.

Skolly "Reference photo (not my bike (sic))"

 

[I like Skol]

Skolly "Reference photo (not my bike (sic))"

I assumed (maybe wrongly?) that the OP has used an internet image of the splines but has circled the 'worn' portion?
Perhaps some additional info/images might help diagnosis of the problem.

 

[Rooster1]

Here we are, photos of the real deal.

The wear / damage is on the left side non drive crank, the inner spindle is perfect.

 

[Rooster1]

 

[Rooster1]

I can buy just the new left crank, its 170mm.

 

[Roseland triker]

Bit of anchor set I'll fix that good......

 

[Rooster1]

Bit of anchor set I'll fix that good......

Thats very helpful, thanks

 

[C R]

I can buy just the new left crank, its 170mm.

From the photos of the crank I would guess that the pinch bolts were not done up properly, which allowed for relative movement between the crank and the spindle, causing the damage. When you get the new crank make sure that the installation procedure is followed, so that this doesn't happen again.

 

[I like Skol]

Here we are, photos of the real deal.

The wear / damage is on the left side non drive crank, the inner spindle is perfect.

View attachment 643067

OK, that is wear and is totally different to the original picture.

As has been said, crank must have been loose to cause that damage, but also splines could engage more. Is the bottom bracket set-up correct? Are there any spacers used on the drive side to adjust chain line because the BB width looks a bit wide?

 

[Rooster1]

The bottom bracket had some play so I ordered a replacement. I did remove the crankset to try and replace the BB and had to give up and put the crankset back on, then on a steep section weeks later I noticed some weird play on the left - thats when it must have got very chewed up!

Hey ho - my bad. I killed it.

 

[C R]

The bottom bracket had some play so I ordered a replacement. I did remove the crankset to try and replace the BB and had to give up and put the crankset back on, then on a steep section weeks later I noticed some weird play on the left - thats when it must have got very chewed up!

Hey ho - my bad. I killed it.

You are not the first and won't be the last.

 

[T4tomo]

its hard to believe it wore that much without the LH crank spinning around on the BB axle, and surely to god that would be noticeable to the rider if the cranks weren't at opposite angles???

 

[Rooster1]

its hard to believe it wore that much without the LH crank spinning around on the BB axle, and surely to god that would be noticeable to the rider if the cranks weren't at opposite angles???

It didn't ever do that.