Mystery resistance?

Do your spokes look like this?

Apologies for the non-helpful contribution.

Put a smile on my face because it took me 30 secs to realise what the fuck you meant, so after the day I have had it is in fact helpful ;D

hah! great reference there.

Tight spot on the chainring, misaligned rear cog, something like that . . . .

If you've done the other obvious things (front wheel spins ok and doesn't rub on brake if you have one) then I'd imagine it's one of the above

is the bottom bracket spindle lenght the same on the new one you installed recently as the old one?

If it's maybe a mil or 2 shorter, the arms that are holding on the chain ring are rubbing the frame when pedaling because of the flex caused but pressure on the cranks.

This may not happen when you just spin the cranks.

Is it just me that is disappointed that "Mystery Resistance" is not a reference to some shadowy organisation hell-bent on overthrowing the state?

Is it only when you go up a hill?

Have you checked the tubes to see if somebody has poured concrete into them?

Too much chain tension can do this.

Yes. Thats what I said. You can have too much... !

have you asked the worm up your arse?

I noticed the other day that my chain ring would appear to either have the teeth cut on it eccentrically, or the ring needs to be adjusted where it bolts onto the crank arm. I store my bike on the wall in the hallway downstairs when at home and the chain is then nearly at eye level. When I turned the cranks I noticed that chain goes tight then slack, then tight again - one cycle per crank revolution - and managed to trace this movement to the front chainring. It still rides ok but I am definately going to sort this out soon.

I noticed the other day that my chain ring would appear to either have the teeth cut on it eccentrically, or the ring needs to be adjusted where it bolts onto the crank arm. I store my bike on the wall in the hallway downstairs when at home and the chain is then nearly at eye level. When I turned the cranks I noticed that chain goes tight then slack, then tight again - one cycle per crank revolution - and managed to trace this movement to the front chainring. It still rides ok but I am definately going to sort this out soon.

most fg bikes (if not all) have this to some extent.

most fg bikes (if not all) have this to some extent.

Especially if you're running Biopace chainrings

I have had this before. its the force.. search your feelings. you know it to be true

Try another crank or a chainring as it may have lost its shape.

Elyptical chainring? If its not round, the chain tension will be inconsistent.

It's probably your rear brake rubbing against the interface between your mudguard, rack, panniers and rear reflector.

oh and BTW, as my Dad always said "bearings behave differently under load".....any skateboarder will confirm.

Eliptical chainring diagnosis seems to be the best bet at the moment, especially as they are the shitty otp FSA/RPM jobbies. New cranks have been on the shopping list for a while, all the more reason to speed that purchase up!

oh and BTW, as my Dad always said "bearings behave differently under load".....any skateboarder will confirm.

Good point, how can I test this though?

It's probably your rear brake rubbing against the interface between your mudguard, rack, panniers and rear reflector.

The flag and the pokey-out side reflector probably don't help either tbh

Sounds like a body puncture.. all the HTFU has slowly leaked from your body.. ;)

the shitty otp FSA/RPM jobbies

As are mine - FSA Vero's. I'll have a tinker and report back if I can make any headway on this.

Have you tried removing the umbrella from your handlebars, taking off the flapping hi-vis vest?

i'd try taking the chain off, going for a roll/standing spinning and see if you can feel anything

Are you towing a pack of dead wallabies behind you?

i'd try taking the chain off, going for a roll/standing spinning and see if you can feel anything

Good idea actually, I could narrow it down to whether it;s the back wheel or not.