Whne I get out of the saddle and "honk" on the above I get a bit of a groan coming from down in the BB area, or seems to be down there. I suspect it's the frame rather than the BB unit/cranks, but I will check them over just in case.

I am a "big" bloke (104kg) so just wonder about the frame integrity. It really hasn't done a lot of miles in the 18 months I've had it. There was no weight limit on the frame stated.

Anyone out there got one and had a similar thing?

Had a similiar issue with mine, changed the BB and greased it up copper good. No issues since. The noice washorrifuc though, drowning out my ipod

Mine seems fine, although I am a bit of a lightweight at 85kg. I have noticed a bit of a creak coming from the bars if I pull hard on those, never really looked for where that noise is coming from.

The cause of the creak is far more likely to be due to a component that needs greasing and or tightening in the chainset/bb area, which is just getting massively amplified by the hollow carbon frame. Carbon makes creaks and knocks sound really weird- I wondered what was going on with my focus until I noticed a brake cable outer lightly vibrating against the headtube!!!

Whne I get out of the saddle and "honk"

Not being funny, mate, but if I was a 16stone+ rider on a budget carbon road bike called a 'Superlight', I'd learn to sit-and-spin like I had glass cranks…

But, yes, it's more likely to be your BB. Maybe a chainring bolt. The 105 BB in my Stealth Pro creaked like a bad 'un and no amount of removing/regreasing/retightening would cure it. Eventually replaced it with another BB and solved the problem.

The thing is the Planet-X is hardly a super light (despite the name) carbon frame. It is a lot more sturdy than more expensive, lighter offerings from mainstream brands.

Bottom headset bearing will be rusty/clicky; take it out and grease it.