Brought a new 2015 enduro from a concept store, still under a year old but last couple of weeks / a month , it has developed a problem when under load, it jumps the rear cassette. Changed EVERYTHING! like for like, been back to the shop twice, they have swapped and upgraded etc, but the fault remains everytime I take it out for a proper ride and not a maintenance stand work through. Anyway, getting fed up/ disheartened / sick of losing out on rides and events because it’s playing up. Now, can I demand they take it back, make them give me a long term test bike while they sort it, or am I stuffed and should be thankful they are still taking an interest. Help please guys

Parts are under warranty for 1 year except normal wear and tear.
Whats everything you have changed?

I’d be assuming dropout alignment, pivot wear or some other frame alignment issue. As above what have they checked and changed?

Changed rear mech, hanger, cassette, chain, shifter. All brand new. Surely when it’s been back at the shop they would have checked frame ailment etc. They’ve set everything up, b-tension, chain length, stops etx. Still not right!!! It’s only a problem when I’m riding it hard, and it’s roughish ground, jumps about. When riding steady it’s fine.

Definitely the chain and not the freehub?

Well that’s what I’m thinking now, bikes under a year old…. Specialized rovels ….free hub should last longer?? And how comes it’s fine most of time, and only plays up under load…if the freehub was the problem wouldn’t it be like it all the time??? Describe to me the effects of a knackard freebub

Cable length? FSR’s need a good loop under the BB, otherwise you can get a ghost shifting.
try a different QR, check for damage to the axle.

Shop swapped shifted from x7 to x9 so, it’s been changed in house. Axel seems fine, goes in smoothly.

free hub should last longer??

Yes it should [/i] but that’s not the same thing as has done/will do.

Anything can break early, the difference between a good and bad product is how often it does, not that a good product doesn’t.

I’m not sure how the rovals work (driver star ratchet?) but I’ve had pawl spring system that slipped under load before when they’d worn a little as they didn’t “spring ” up all the way and only lightly engaged.

is it ghost shifting of dropping the chain.
is it dropping it on the front or back?
are you pedalling hard on rough terrain and losing the chain?

Are your chainring bolts tight.? Had a similar problem as steel city a few years ago.

If you can make it happen at will on a certain bit of ground then try and get a mate to film you and see what’s going on with the chain etc as it happens?

Freehub on my Specialized (Specialized own brand hubs)went after about 6 months.Just needed new pawls and springs.

Well I would expect a freehub to last longer but it depends on mileage and if it’s been looked after so the onus is on you to show it’s been serviced really. of course sometimes things break prematurely (manufacturing error or bad design), they break due to an event or they wear out early due to lack of lubrication.

Cable length was my first thought but I didn’t think about the suspension effect Speshpaul mentions so that is the first thing to check along with frame/hanger alignment.

Freehub if failing would normally slip under heavy or shock load, the latter happens more on rough ground and and your legs will jerk around as it jumps and if severe you feel like you are going to go over the bars – just like when a chain slips/snaps.

Why did you change everything and who paid for it? I would only change something like a shifter and mech if I knew it was faulty or had good reason to believe it was. Your opening post sounds more like clutching at straws. A chain can be measured and a cassette visually inspected and then go off the chain wear.

Describe to me the effects of a knackard freebub

Well, when I break freehubs the normal way is for it to skip under load on the top 1-2 cogs. That’s because of how I break them though – I put a fair amount of force into being in entirely an inappropriate gear which means that the cassette starts eating into the freehub. Once it eats past a certain point, those top cogs will have a small bit of movement under load, and even a tiny amount can cause it to slip under high load.

Quite honestly though, the best thing you can say to the shop is that if the frame is straight, mech hanger is straight and gears have been swapped, that you want to try a different rear wheel to rule it out as the cause of the problem.

It’s set up 1 x 10, losing the chain at the rear, from halfway down to the bottom, hard pedaling downhill it’s jumping (or giving the same feeling as jumping) like if u stop pedaling for a split second and carry on, it has to re-engage. It’s like a knackard ratchet kinda feel, when they start slipping.

11-36?

U changed the mech as advised by my local shop, chain and cassette needed changing anyway. I keep thinking bent rear triangle, but it runs fine most of the time, only when I’m pressing on. Might get them
To look at the freehub. Had issues with the last x9 on it, and they changed the stops as they kept moving( replacing the block housing as advised from sram) could it be another faulting mech (brand new and less than 100miles!!!) x9 type 2

Yes 11 36 and a 34 upfront NW

swapping to a different wheel for a test should be easy enough?

u stop pedaling for a split second and carry on, it has to re-engage. It’s like a knackard ratchet kinda feel, when they start slipping

sounds very much like the free hub

souunds as though the free hub is tight as much as slipping, do you get the chain going slack when not pedalling?

Nah chain doesn’t go slack, or at least not that I can see. Was gonna try and film it on my gopro to prove to the shop I’m not just talking rubbish!

Take it to a different shop and (pay) for an inspection/another opinion.

I’d focus on the freehub and alignment of the rear triangle/main pivot etc have been removed and reinserted?

It could be a glaringly in-your-face issue that needs a new set of eyes to spot instantly IMO-

The fact that it wasn’t doing it and now it is points to wear or something bending. Unlikely to be a warranty issue unless you can prove it wore or bent to easily.

Try rolling along slowly and back pedal slowly, see what happens with the chain, that can sometimes show up a dodgy free hub.

Main pivot bearing.

Cable is the most obvious thing to me.

what is the rear mech exactly? Does it have a clutch?

Stiff chain link? I’ve seen these cause vaguely similar problems.

You say your chain and casette were changed as they were knackered anyway but you don’t mention your front chainring . I would check that the new chain isn’t slipping on the used front chainring under load .

Front chain ring is new as well. When I say the drive train is new, there’s nothing you can suggest that hasn’t been changed. Rear mech a type 2 x9. Why would the main pivot bearings cause this? I’m trying a different rovel wheel tonight to eliminate the free hub. Fingers crossed