I've lost a few rear mechs this season due to the amount of mud/grass clogged into the rear mech jokeywheels. this stops them from turning then they get jammed and the hanger snaps or bends leaving the mech all twisted or worse in your spokes.
apart from single speed anyone any idea's?
1) better jockey wheels
2) long mtb mech
3) single ring upfront
all around the crank and front mech get caked then the chain drip feeds the rear mech & cassette with mud & grass.
any ideas welcome
I tried 1). It didnt work. Ive seen people with single front ring have the guide (mtb style front mech replacement) jam with mud. The single front with bash works better but can clog and then unship the chain. Only success i had was to really over-coat the chain in wet lube, and wipe a enough off so it dosnt drip but is still loaded with it, still not perfect tho.
Oh, and campagnolo is useless in the mud... as youd expect really.
its a freeking nightmare, I couldn't put the power down yesterday as I could hear the mech locking up. eventually it broke with half a lap left.
what about some kind of chain device that scraped the bulk of the crap off before it reached the back?
Mine snapped on a really muddy race last month. A bike mechanic suggested I should make sure the frame/mech hanger is aligned
sop i borrowed this
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and it's been fine. Not saying that's the solution but may help
Ive seen people with single front ring have the guide (mtb style front mech replacement) jam with mud.
Bugger, maybe double chainguards is the way to go on my singlespeed build then.
Try 10 tooth jockey wheels for a little extra clearance !?!?!?
Sturmey Archer (or similar) rear hub/gears?
Never back pedal is deffo one simple piece of advice 🙂
I run smaller jockey wheels and just try to take the cleaner lines aim for pudles etc. Works most of the time.
Pit bitch n second bike FTW = nice clean bike at start of each lap!
None of your options change the effect or amount of mud / grass / crap.
Either fit some hub gears, SS or try to aim for the puddles and avoid the grass/mud.
Back when I raced, I snapped one and bent another. The solution for me was to think about saving the bike abit. I could ride sections that others struggled with, but it would end up clogging the bike, so I learn to run them instead. Cross can become a different game for those with one bike as opposed to having two.
the only way to prevent this really is by having 2 cx bikes and a pit bitch with a jet wash, at the national trophy yesterday I was changing bikes every lap and those that Had problems were guys with only one bike
Some of the fast lads in our league revert to bikes with an 8 speed rear set up when conditions get really bad. This is of course in addition to spare bikes, helpers and jet washers in the pit area.
how would 8 speed help?
8spd doesn't help. 6spd was about the last cog spacing that worked better in mud.
Not sure, but everything a wee bit wider - chain, space between cage arms, space between sprockets etc. All a little bit more mud resistant.
Make sure it's all immaculate before the race.
Any sort of wear on the cassette, chain, jockey wheels etc multiplies your problems exponentially. I'm not saying to buy a new groupset before every race but the less worn it is the better.
Cover the whole lot in GT85 before the race. Seat and down tubes, back of the fork where the mud gathers and all over the cassette and mech. It won't last long but it'll delay that first build up just a little.
Don't change gear under pressure, don't back-pedal.
Don't do a warm up lap on the bike your going to race on!
Love that, 3lb of mud on your bike and your brakes half blocked before the race has started....
Last race of the season was yesterday so I don't mind saying it now but I've never had the rear mech thing, it's always been fine, no idea why, even in truely horrible conditions and the one bike.
I just put it down to me not being fast enough or strong enough to put the force through the cranks.
what mech you running?
ive had both apex and rival jam. basically the jockey wheels jam and then it doesn't take much force on the crank to bend or brake the hanger, or bend the cage on the mech.
I just put it down to me not being fast enough or strong enough to put the force through the cranks.
You still managed to lap me though Dan ! moments later my mech jammed snapping the hanger and dumping everything into the rear wheel. Running the last lap and a half just about killed me. I don't think speed or strength come into it much. I put it down to the muddy wash you threw over me as you came past.
don't do cx races.
2 bikes and a jet wash is the way to go. Had 3 bike changes yesterday at Shrewsbury (Trophy Series). Some of the elites were changing every 1/2 lap in the afternoon
Based on a totally unscientific series of observations I think 9speed MTB is better.
XC Neil, I was there as well! some where even changing every half lap!
A few things I have pick up working in the Pits at CX races. (some mentioned above!)
Start with a CLEAN bike (clean the jocky wheels)
take wheels out and polish the frame/parts (fork juice is good)GT85 is OK. (makes cleaning quicker as well)
Swap bikes every lap
don't back pedal.
change gear before corner/bank not on it or powering out of it.
But the best one I heard for really muddy races, adjust the limit screw to block out the largest gear at the back, less chance of going into the spokes.
8-speed XTR or XT cassette with lots of cut-outs to clear the mud.
XT or better rear mech with cartridge bearing jockeys full of grease.
9-sp chain with slots in plates such as KMC X9SL.
Conventional front mech...top-swing act as a very good mud trap.
Never back-pedal.
Do not go for full-power shifts, always back off a little like you had to 25 years ago.
Lots of wet lube on the chain and mechs.
Lots of little things all add up.
PaulD
The one guaranteed method is to give up cross. I did and have had no trouble at all since then... On a more serious note, mech hanger straightener is invaluable. I found that some nugget or other would leap from his bike onto my rear wheel every race (I did 3 races, ended 2 with no rear mech), perhaps I should take some responsibility but in my mind I was there to ride a bike, not carry the damn thing!
Have you considered one of those steel roo-bars for a rear mech that comes on kid's bikes?
I have one on a roady that looks awful, but it has totally protected the mech in several washouts, particularly on the ice.
It would work to fend off the competition....
PaulD
I put it down to the muddy wash you threw over me as you came past.
Sorry Colin! I think i ended up running at least half a lap every lap yesterday, my shoulders bloody killing today, that helps mind carrying it up out of the mud while your running.
Had this problem on Saturday at the csp cx in clitheroe, got to the top of the hill on lap one, remounted and it snapped, I was fuming!
Im on a run of bad luck at the minute with another one a few weeks ago at Bolton!
Tried spraying silicone dashboard shine all over the drivetrain which worked on wetter courses. However the leaves and grass still get stuck in there, so having a spare bikes the way to go!
Ripped mech has only happened to me once in the last 15 years of racing 'cross so I've been lucky. But if anyone can tell me how to keep the blasted chain on the front inner chainring just as I'm about to remount the bike I'd be grateful to know. Came off four times at hillingdon yesterday. Each time I put the bike down it came off. I always put the bike down carefully, so really don't know why this is happening. Is a medium cage rather than a short cage rear mech a better bet? The chain is the right length btw.
yeah it happened at Clitheroe! almost did it at Bolton too. and it broke at Beacon park.
I cant go down the 2 bikes route.
Ripped mech has only happened to me once in the last 15 years of racing 'cross so I've been lucky. But if anyone can tell me how to keep the blasted chain on the front inner chainring just as I'm about to remount the bike I'd be grateful to know.
Get a chain keeper that attaches to the front mech. Token do them and they are about £8 on ebay.
As for mechs, keep them clean, run a short a chain as possible so prevent slack and your mech flapping. Plenty of oil if you are only on the one bike. Gentle shifting, not under power.