Lake district routes

There is a cycle path along some of the A66, if going toward Keswick you can take a cycle path on the RHS of the A66, cut through Threlkeld and then cross the road and go via the Castlerigg stone circle into Keswick - much better than the route on the Fred Whitton etc. Cycle paths and roads are fine, I ride them on 23mm race tyres.

The A591 you're more stuck with, but its not too bad. When you get to the top of dunmail raise (I assume that's what your doing if going from Rydal to Thilmere), which is a bit of a grim climb, you can take the side road on the left rounf Thilmere which is great. From the end of that you can cut through St John's in the Vale to Keswick with is also grand.

You can follow the C2C. There is a big loop that goes through Mungrisdale, which you may be able to cut short if you want to. The railway section just outside Keswick can be avoided by taking the minor road from Threlkeld that runs South of the A66.

For the initial part of the route to Troutbeck just follow the C2C route 71 signs.

reading the c2c reviews, 28mm to 35mm tyres are fine even 25mm if the weather is good. That depends on what bike you own, can you swap to a larger tyre. Also what type of tour are you doing, fast point to point or take in the scenery slower ride?

There is a cycle path along the A66 between Keswick & Penrith. Some is Sustrans style converted rail route, some is path style. I used it last year.

There are plenty of side roads along the A66. Makes the journey alot longer. Probably steeper but alot safer.

The A66 into Keswick is on the route of the Fred Whitton. It's nice and wide so you shouldn't be too bothered by the traffic. Some parts have a decent bit of shoulder if you want to be off the road. The cat's eyes are huge so be careful of them. I hope that you get as much of the Fred route as you can. It's fantastic.