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Brian
06-28-2006, 08:00 AM
While climbing a small hill on a club ride last night, my Ksyrium SSC SL freehub went out on me. One minute everything was perfectly fine and the next I was pedaling like a madman and going nowhere. At first I though I dropped the chain, but the chain was in contact with the chainring and cassette. When pedaled, the cassette was spinning perfectly; it just wasn’t turning the rear wheel.

Fortunately, I was only a mile into the ride when it happened so it was a short walk/coast back to the car. When I got home I removed the cassette and started playing with the freehub. When I operated it by hand, it seemed to work just fine: ratcheting as I turned it counter-clockwise and engaging the pawls as I turned it clockwise. So I put the cassette back on, but when I went to tighten it the cassette simply spun clockwise under the force of the wrench.

Do I need a new freehub? Can it be repaired? If freehub repair is a nasty endeavor, let me know and I’ll drop it off at the shop. If it’s a fairly straightforward task, feel free to provide some basic instructions and I’ll give it a try. Considering it’s already broken, how much more can I break it?

Thanks.

KJMUNC
06-28-2006, 08:56 AM
Brian, my hub started acting funny last week and I decided to go the DIY route this time too. There's a decent .pdf file on Mavic's website on how to dismantle and service the hub.

http://www.mavic.com/ewb_pages/m/maintenance_FTS_L_461.php

I've had several Ksyrium hubs fail like that over the years and I guess I've still yet to learn my lesson. As bomb-proof as they can be, they still require servicing/lubing every couple of thousand miles, especially if you ride in the rain/grit.

Sorry I can't help with exactly what happened, but at least maybe this will steer you in the right direction. For what it's worth, I had my LBS service a free hub (not repair it) for $20-30. I think a new freehub will cost you $70-80 before labor.

znfdl
06-28-2006, 09:18 AM
Brian:

I have had a couple of freehubs stop freewheeling, no amount of lube would get the freehub moving again. Additionally, my rear Ksyrium started to make pinging noises when climbing so I decided to give up on the Mavic kool aid and had Ergott build me a set of wheels.

Brian
06-28-2006, 09:50 AM
Thanks, KJMUNC. I printed out the Mavic Free Wheel instructions last night.

One of the steps says to REPLACE the FTS-L free wheel body kit and install the NEW one. Did you replace any parts or simply disassemble, clean, lubricate and reassemble?

Ken Robb
06-28-2006, 11:49 AM
I swapped out a Campy for a Shimano freehub on a set of Ksyriums easily.

bostondrunk
06-28-2006, 11:53 AM
http://www.excelsports.com/new.asp?page=8&major=6&minor=8&description=Cassette+Body+FTSL&vendorCode=MAVIC

Brian
06-28-2006, 11:56 AM
Thanks, BD. I'm hoping I can clean, relube and be on my way. Nice to know that ordering a replacement is just a clikc away.

bostondrunk
06-28-2006, 11:59 AM
Keep in mind it says it doesn't include the pawls. Not being a wrench, I assume those are the two pieces that each have a tiny spring under them, that the body slides over when installing. So don't lose those, those tiny springs can go flying if you take the body off too quickly.

Brian
06-28-2006, 12:03 PM
I noticed that too. The instructions I printed out from the Mavic website kindly remind that the pawls and springs will pop out if not supported during free wheel body removal. And you know those stupid little springs will be the EXACT same color as the floor you are working over...

KJMUNC
06-28-2006, 12:17 PM
Brian, I actually haven't undertaken my little project yet....was a lot easier to just swap wheels, but I'm planning on doing it this evening, so I'll touch base with you if I find anything that I think might be helpful to you.

vaxn8r
06-28-2006, 12:19 PM
That happened on my tandem with some WTB hubs. Fortunately WTB sent me a brand new hub as it could not be repaired. Unfortunately I still had to have the wheel rebuilt. Not sure why it couldn't be repaired but...it couldn't.

Brian
06-28-2006, 02:37 PM
KJMUNC,

I took apart the rear hub at lunch. The only tricky part was figuring out what the "fork support" was in Step 1 of the Mavic instructions. The fork support is the end cap on the non-drive side. You simply give it a firm yank and it pops off. Only then can you insert the 10mm allen wrench.

After that, getting everything on and off was a piece of cake. I was actually surprised at how few parts there were. And heed the warning about the pawl springs. When you pull the free wheel body (the metal cyclinder that the cassette mounts over) off of the internal pawl/spring assembly cyclinder, the pawls and VERY SMALL springs WILL launch. I did it in a small bucket to catch everything and was glad I did!

onekgguy
06-28-2006, 09:32 PM
I'm finding my Ksyrium hubs need to be lubed much more frequently than other hubs I've had...1500 miles max. On today's ride I started getting a loud squeal at speeds over 30mph...not a big problem except I was 35 miles from home. Toward the end of the ride I couldn't go over 20mph without getting the squeal. I brought them into the shop tonight to let the techs there work their magic. I suppose in the future I should just do the preventative maintenance myself now that I see it's not that difficult.

Thanks for the links.

Kevin

bostondrunk
06-29-2006, 06:55 AM
I'm finding my Ksyrium hubs need to be lubed much more frequently than other hubs I've had...1500 miles max. On today's ride I started getting a loud squeal at speeds over 30mph...not a big problem except I was 35 miles from home. Toward the end of the ride I couldn't go over 20mph without getting the squeal. I brought them into the shop tonight to let the techs there work their magic. I suppose in the future I should just do the preventative maintenance myself now that I see it's not that difficult.

Thanks for the links.

Kevin

Do you just put a few drops of oil on the inside of the freehub body, or are you supposed to apply directly to the pawls? Anywhere else? I too was suprised how few parts there were to deal with when I saw one taken apart a couple of weeks ago.

onekgguy
06-29-2006, 07:32 AM
Do you just put a few drops of oil on the inside of the freehub body, or are you supposed to apply directly to the pawls? Anywhere else? I too was suprised how few parts there were to deal with when I saw one taken apart a couple of weeks ago.

I don't know because I've always let the shop do it for me. I'll ask the mechanic when I pick up my wheels today. I think this may be one of those fixes I'll begin doing myself as it needs to be done often enough.

Kevin

onekgguy
06-29-2006, 12:30 PM
I just picked up my wheels and the mechanic could find nothing wrong with them. I was sure the bearings were going bad and at the very least he would find one of the hubs in desperate need of lube. He relubed the hubs and we both agreed that the noise had to be hub related as nothing else could make that sort of squeal. I dunno...has anybody else had similar problems with their Ksyriums?

Kevin

soopa
04-20-2008, 12:23 PM
There's a decent .pdf file on Mavic's website on how to dismantle and service the hub.

http://www.mavic.com/ewb_pages/m/maintenance_FTS_L_461.php


Does anyone have a copy of this service document from Mavic? Their new website sucks.

dvs cycles
04-20-2008, 01:06 PM
Does anyone have a copy of this service document from Mavic? Their new website sucks.
Save this info.
username: mavic-com
password: dealer

http://www.tech-mavic.com/tech-mavic/technical_manual/data/index.php

97CSI
04-20-2008, 02:49 PM
There is an excellent video by the Rogue Mechanic http://roguemechanic.typepad.com/ on taking apart and reassembly of the Mavic rear wheel.

When I pull the freehub I use a screwdriver to dab Mobil 1 oil onto the pawls and inside the freehub on the 'teeth' that the pawls ride in and also on the nylon bush. Don't want to over-do-it as the oil will attract dust. Mavic doesn't use grease - they use oil and Mobil 1 is as good as it gets.

BTW - If anyone needs any Campy 10/9-speed Mavic freehubs, I have a couple of new ones for sale for a good price. PM me, as this isn't the classifieds.

TAW
04-20-2008, 04:43 PM
I may be late to this discussion, but I've overhauled quite a few of these hubs and I would suggest that you also need to replace the pawls. Those springs can get worn and that's what causes the slipping. In most cases that I've seen, the freehub body is o.k., but the pawls (springs) are worn and don't engage properly.

Also, invest in the Mavic mineral oil. Other types of oil will work, but the mineral oil is the best.