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Capital punishment for the bikes. How to fix mud induced mechanicals
After the epic ride in canberra over the weekend, thought today would be a great day to go for a quick spin as the sun was beaming. However as i was running over my bike everything was wrong with it!! Stiff cranks, hardly anything left on brake pads, stiff headset, stiff shifters. thats the stuff i notice straight away without riding the poor thing.
So a few questions;
Does stiff cranks mean i need a new BB
Does stiff shifters mean i have to replace the housing and cabling
And are there any other things i need to look over after long rides in muddy conditions?
I was wanting to do as much as possible myself, as i want to learn how its done. Any hints or advice?
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I also did Capital Punishment and my cranks had almost siezed!
I pull the BB out and pressed the bearings out of the cups.
Two new much better bearings cost me a total of $20
Pressed the new bearings in and fitted it all back up.
Feels as smooth as butter now and cost a whole lot less and have better bearings.
After doing this I will never buy a new BB!
About to go out to the garage and put my bike back together now as I stripped and cleaned it last night after doing the Capital Punishment.
Your stiffness is probably grit so you need to do a clean. Rather than diagnose yours I'll list what I have done which is a normal strip down after a ride like this:
- wash bike
- remove chain and soak in citrus degreaser
- clean dérailleur's with citrus degreaser & toothbrush
- remove cranks and bottom bracket and clean, regrease and re-fit
- remove gear cables, blow TF2 spray through all housings, allow to dry then re thread & attach gear cables
- remove forks, clean headset bearings and inside head tube then re fit everything
- remove anything else with a bolt, clean bolts and threads etc then re fit
- new pads
- most likely new chain required
- lube chain & cables and grease every bolt
If the bearings in the bottom bracket and head set seem gritty when you rotate them when cleaned then soaking overnight with TF2 spray will fix.
All sounds easy doesn't it? Now I'll go to the garage, re build mine and hopefully all will work and I can get an early night
and on how far you want to go...
If your chain is worn past 1% elongation, you have two options:
1: Replace the lot - chain, chainrings middle and granny, cassette. This is the option to choose if you move wheels around between bikes
2: Keep riding current transmission until chainsuck becomes annoying. However, I wouldn't advise using anyone else's wheel without changing over to your cassette first, or they might not like you for very long.
If it's longer by 1/2% you can get away with replacing just the chain. If it's between 1/2 and 1% you need to put in a new cassette as well, as you are going to trash the new cassette. Replacing just the chain after more than 1% chain stretch will result in the new chain skipping on the old cassette.
+1 on replacing just the bearings out of the BB assembly.
@VTSS: how did you press them out, exactly?
I have to say that I enjoyed the course - just not the streams of water and mud.
I had greased and cleaned the bike before the ride. My gears had seized, brake pads gone to metal,
my front tyre valve fell out into my hand, seat was shagged,headset grinding, etc.
I washed the large chunks of mud off, then stripped the bike down to a basic frame, greased the headset, derailleurs and replaced the tube, brake pads and derailleur cable and seat. Rode it today and it's good as new!
Can't wait for next year!
Out of interest, Paul did you go through a full set of metal/sintered pads? Or were they a resin type compound? I'm guessing the Sintered pads would be better for enduro type events and wet weather? Just curious so I know what to put in my bike when I enter an event.
I went through my rear pads to the bone too and almost got there on my front. I guess the rear pads would have received more mud/grit. They were the genuine Avid semi-metallic pads too not the cheaper alligator version which dont last as long and mine were only about 1 month old!!
I never knew you could go through pads so quickly. I heard so many stories of brakes failing on the day. Saw it first hand too, guys going down some of the hills with their feet dragging on the ground!! Even happened to some of the guys doing the 50k. Goes to show if you're going into an event like that you should go in with a fresh set of pads.
Thanks for the advise guys.
So I guess it wouldn't be a bad idea to throw a set of bedded-in pads into your kit if the weather isn't looking good. 30 secs work, if you run out of pads.
I better start a list. lol
I carry a set of pads when I ride. You just never know
Hey. I wanted to share with you some thoughts on the brakes / pads issue at CapP.
Again - its a tip from home (mud island) that I employed to great effect on Sat. I went round in 5hrs (almost exactly) for the 100km.
It seems counter-intuitive in a race, but just slow down! Up the front, there was a pack of us (maybe 8 riders), I would hit the single track, and would consciously go much slower than a normal race - i.e. not snapping out of every corner in a sprint, only to lock the wheels up/ apply significant braking force at the next corner.
Guys were swearing at me (there is very little polite use of 'track' or 'rider'), shooting past, braking late into corners and I knew they would have killed their brakes by the 30km mark. I knew I would see them again.
I kept it in one gear on the singletrack (minimising chain damage) and this was much lower than normal,so I just couldnt build up too much speed.
I'm sure its something that you all considered, but if you keep your strength and braking for the fireroads, you're overall speed would be verysimilar, and your bike would have thanked you for it.
Like F1 racing - you always hear of them 'conserving' their tyres and brakes in hot conditions. Its the same on the mtb.
Just a thought. And it might come in useful at Husky.
I use Hayes sintered pads, my rear ones had been on the bike for about 6 months already and when I finished the 100k's I still had a couple of mm's of pad left. The front ones are fine and I don't need to replace them at all.
I guess if you use your brakes a lot they'll wear quicker
Hi Guys,
Long time reader, first time poster. Just wanted to say thanks to everyone for all the tips going into Capital Punishment, i surely wouldn't have made the finish (100km) without the extra info. Bringing myself slowy to assessing the damage... There is alot of talk about brake pads, but not much reference to rotors. I went through my pads (Shimano Resin) and have subsequently gouged into the rotors (Shimano SM-RT1) and so will be replacing them. Whilst i don't ever plan on riding in such conditions again, what are thoughts on rotors i.e. wavy vs smooth curve, bigger cut outs vs smaller, ones to stay away from in particular?
Also replacing gear cables, anyone gone to fully enclosed, or a bit of an over kill? Would prefer not drilling out cable guides unless it is strongly recommend. Again any particular brands to go for/stay away from? (Shimano Deore shifters/SLX derailers)
Cheers.
Go full length cables for sure - best improvement for long term smoother shifting.
You don't have to drill the cable guides, just go round them and use a tiny cable tie to fix the outer next to each.
+1 for full length. This was one of the first mods I did to my new bike. As Cannondale have removable inserts there was no hesitation in drilling them. I converted the Giant and think I just cable tied them.
If you can stretch to it, go for Gore cables. Full length, completely sealed against all elements.
Fit and forget.
You dont need to drill then. The cable is housed in a super thin goretex sheath all the way, and you'll only putouter where you would do normally.
Wiggle and CRC sell it, as would your LBS (at twice the price).
Wavy, well 'holed' rotors will shed the mud more, making for quicker riding, but will wear disks more. Its a trade-off.
For all you guys that had pads wearing down to the backing plate I'd recommend checking your rotors also. Chances are they've been scored by the grinding of metal on metal and because they can't be machined (such as the discs when you leave it too late to replace the brake pads on your car) they'll need replacing too.
That's what happened to me at last year's Sydney 24hr.
Yeah - sorry to be the bearer of bad news, but for those thinking, "Meh - so the disc is damaged - I'll live with that" - don't!
Once the disc is damaged, because it is now rough it will eat any new pads installed very quickly.
As BT said - when you've been down to metal on metal for a while (as sounds the case in CP) you'll need to replace rotors & pads at the same time.
My bike hates me after this event, it's been moaning and grinding, squealing and refusing to go anywhere with me.It's gonna take some work to restore our smooth running relationship we had.But i thoroughly enjoyed the event.
Hey Rob, have you done that to your 575?
Do it for sure! I've done it on my SC in the fashon mentioned. They're just cable tied to the existing tabs. Looks as neat as the original but now is also colour co-ordinated.
Yup - full length on the rear. Given I built it myself
Don't tell me that's not how they come from the LBS?
The 575 frame has (brilliant) cable stays for full length cables as standard. Actually I can't see how you could fit non full length, but I've never tried.
My brakes were just as good after the 100km as they were at the start. I've always used full XTR and have never found them great at slowing me down but accepted that's the compromise for weight savings. Earlier in the year I changed rotors for a lighter weight FRM rotor which has hardly any metal. They are all air gaps. I immediately found my levers were more solid and braking was much better. I've now done 2 events in the wet this year and found on both occasions the brakes were solid to the end.
As for pad wear, I think that has to do with braking technique (as well as quality of brakes). I've raced rally cars for more than 20 years and on a typical stage of say 20km we would be braking say 400 times which heats the discs up to 800+ degrees which obviously wears pads & rotors very quickly especially these days with turbo cars going so much quicker between corners therefore requiring greater braking force to slow them down. The trick on gravel roads is to brake very heavily but get off them quickly so you basically jump on them as if a child has run in front of the car then get off them and on the gas. This means you break effectively but don't spend too much time on the brakes allowing them to heat up. I use the same technique racing my bike and get great pad wear. I've done about 3 months (4-5 days/week) on my current pads including the Dirtworks and Capital Punishment and am now down to about 1/4 left.
Also, re the full length cable debate, I now run no outer cable at all except from the lever to the frame just near my stem, and a small piece at the rear derailleur. All the rest is inner cable only so that also ensures no shifting problems in the mud.
and a rebuilt wheel .....and my punishment is complete....mind you the 50km of the course I did ride was the most fun on a bike without throwing up you could have!
Just to add a balance to all the full length cable posts....
Full length is ok with hi quality cables and regular maintenance.
They are also good when you have a lot of crappy weather.
But.... Once the frame is drilled you can't go back.
And even slightly dragging full length cables will turn your shifting to slow motion.
I've been running regular cables for many years, including two Jet black 24hrs which were 'pure mud' events.
My tip is to use very light grease on the cables. I use buzzy's slick honey.
The comment on Gore cables is very good, and another option is to use SRAM/Avid Flack jacket cables that have a teflon inner over the cable between the cable stops, giving it a sealed system without the drag of full length cables.
Don't use regular 'bulk bike shop quality' (XT or basic SRAM outer) with non-teflon coated cables for full length conversions and expect crisp shifting for more than a few weeks. If you are going to do it - invest in quality cable.
That's my two bob's worth!
W
@Rob, it's sad but true.
@ladytoast, I'm not sure what you mean when you say 'brilliant'?
My 575 arrived with exposed cable for the front der (The guys at BA have never understood why Yeti did this?) I would need to drill the stops or cable tie to go full length. But FWIW it had never given me any problem being exposed tho. How have you got yours setup? Have your stops been drilled?
Mine came with exposed front derailleur cable and a full housing on the rear. I don't think that you can run a full housing to the front as there is no cable stop near the derailleur ( unless you stick one on...)
I've just finished getting my bike back together after last weekend and threw on some new inner and outer cables as the old ones were past their best even before exposure to the battlefields of Canberra. Feels lovely !
Chain and cassette were cactus as expected. Brake pads were ok ( I never got to go fast enough to need brakes ....). Chris King BB was like new, although the CK headset had some crap under the outer seals. A quick clean later and it looks fine and still feels beautifully smooth.... Very impressed with both. I stripped the wheels down and think I may need a couple of new bearings ( Crossmax ST's). The driveside front and brakeside rear bearings are feeling a little rough. It's been a long time since I checked them so they may have been a little rough even before the race....
I'm not the fastest spanner monkey in the world but it's taken me the equivalent of about 3 days to get everything cleaned and serviced..... oh well !
CB
Fatboy makes a good point about short and sharp braking. The pads wear by rubbing, so the less time they are in contact, the less wear you will get. (By that I mean a long slow stop from a given speed will wear the pads more than a short rapid stop form the same speed). The greatest amount of wear, though, comes when the mud and dirt gets between the pads and the rotors and wears away at the pads and rotors while you are just riding along and not even using your brakes. You hear that rubbing noise that gets louder after you have ridden through a puddle and the mud supply has been refreshed between the pads - that's when the majority of the wear is taking place (that't also the sound of $$ signs floating away!). Sometimes gently applying your brakes when you are riding along can help clear some of the mud. It doesn't alway work though - I ended up metal on metal by the end of the race.