We built my son Max's new bike up (he's in growth spurt mode so is being expensive!). 

The Forme Calver is a really well made frameset, good for road and cx (but lacks clearance for really wide gravel tyres), except for the cable routing for gear cables...

The Vitus that it replaced has full length outer from shifter to rear mech - which is awesome. 

Unfortunately, where the cable enters the down tube on the Calver, only the cable inner wire goes into the frame, to exit through an inner wire sized hole at the bottom of the down tube. 

I initially set up with SRAM Slickwire cables which have been great on the other bikes, but on the Calver the shifting was sluggish. 

On the recommendation of Alex Forrester (my local Calver expert), I ordered some Jagwire Road Elite Sealed Shifting Cables. 

They sorted the sluggish shifting immediately. 

They look like a close copy of the old Gore-Tex sealed cables which went out of production when electronic group sets became established - I was very disappointed when that happened. 

The Jagwire cables are a little different though, these have a form of wet lube inside the housing liner. 

Fitting is a little more fiddly than regular cables, but the instructions are well written. 

If your frame has internal cable routing, where only the inner cable goes through the frame, which results in sluggish shifting, these are highly recommended.

I'll update the review if with time I feel differently, but so far so good.  

Update: The coating on the inner cable has come off inside the lever and at the point where the cable goes into the down tube. This was frustrating given the cost of these cables but a new stainless inner cable (non coated) is working well.  

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