campy record 10 chain slip problems

[kweil]

I hope someone can shed some light on this problem. I have a 2003 pinarello prince with campy 10 record group. The problem i am having is that when i am in top gear (big front small rear) and stand up to sprint the chain slips very bad. This problem caused me to go down very hard about 5 weeks ago. I broke my back in 2 places and my pelvis durring this wreck. I took the bike to the shop where they kept it for a month. I picked it up today with a clean bill of health. I rode it for about 25 miles and stood to sprint and the same thing happened again. This time i did not hurt myself like before but needless to say i am quite upset about this. I have noticed that both times the chain was off when i picked up the bike. I dont know if this is a component problem or frame problem. I am large at 6'3" tall and 200 lbs. I know i put out a good bit of power in a sprint. Is this problem possiably caused by the rear stays possiably shifting to the drive side due to flex in the stays? The bike does have quite a bit of mileage on it. I have lost confidence in the bike shops around dealing with the problem. any insight would help. Oh the chain and rear casette have 600 miles on them and were replaced together. thanks

 

[mjmc1273]

I hope someone can shed some light on this problem. I have a 2003 pinarello prince with campy 10 record group. The problem i am having is that when i am in top gear (big front small rear) and stand up to sprint the chain slips very bad. This problem caused me to go down very hard about 5 weeks ago. I broke my back in 2 places and my pelvis durring this wreck. I took the bike to the shop where they kept it for a month. I picked it up today with a clean bill of health. I rode it for about 25 miles and stood to sprint and the same thing happened again. This time i did not hurt myself like before but needless to say i am quite upset about this. I have noticed that both times the chain was off when i picked up the bike. I dont know if this is a component problem or frame problem. I am large at 6'3" tall and 200 lbs. I know i put out a good bit of power in a sprint. Is this problem possiably caused by the rear stays possiably shifting to the drive side due to flex in the stays? The bike does have quite a bit of mileage on it. I have lost confidence in the bike shops around dealing with the problem. any insight would help. Oh the chain and rear casette have 600 miles on them and were replaced together. thanks

I run a Campy Chorus setup on a Orbea Onix and have not experienced that type of issue. The only things that come to mind are the the chain might be too long, the chain has a frozen link (likey where it was joined) or the free wheel is messed up.

You broke your back in two places and broke your pelvis five weeks ago and you are back riding????? You are a very fast healer my friend

 

[kweil]

the wonders of modern medicine. yes 5 weeks ago and started riding again after 3 weeks. I have been taking a heavy dose of meds and growth hormone. I guess I wont be riding for a while after todays fall. I think i tweeked my pelvis again but the back is ok. There was a distinct pop when this happened . I have a dura ace group think i might try it on there to see if its any better.

 

[kweil]

If it helps the bike shop said that the chain was to short so they added some to it. they also said they adjusted all the cables. I am thankful despite how hard i have gone down the bike has escaped with no other damage.

 

[CAMPYBOB]

Weird...I was also going to suggest that the chain was too long, yet the shop added a link?

The derailleur may also need the wrap/tension screw adjusted.

A new chain and new cogs should not slip.

BTW, one of the guys in the local club also did the same trick back in July. He was riding high mileage Shimano gear and when the chain skipped he went down hard. I thick he cracked his pelvis and was off the bike 7 weeks.

Good luck with your recovery, kweil.

 

[Yojimbo_]

Chain slip can be caused by a worn out chain, or worn out cogs, or both.

Did you replace the cassette and front chainrings as well as your chain?

 

[kweil]

the chain an casette were replaced together. The problem only occors when standing and sprinting. The chain seems to bind and then you hear a pop and the chain comes off. I was wondering if this is a component problem or a frame issue. could it be the rear stays torquing to the drive side due to age of the frame and carbon stays. It makes some sense to me that if this is happening that it would cause drive train alignment issues that could result in the chain popping off. It has been mentioned that the freewheel could be messed up. what could i look for with regard to the freewheel. I dont want to ride this bike until the issue is cleared up.

 

[kweil]

yojimbo. I did not replace the front chain rings. I would have thaught they would have checked this at the shop at the time. I dont wish to take it back to them. I will look for wear indications on my own. when the rear cassett was replaced It was due to chain slip. I replaced rear and chain at that time.

 

[sogood]

Why are you sprinting on large front small rear?

 

[alfeng]

Why are you sprinting on large front small rear?

+1

It has been my understanding that it is much more efficient to begin the sprint on something like the 14t cog & (unless you are McEwen) possibly upshift to the 13t or 12t.

 

[kweil]

I usually start out in a lower gear and ramp up the pace. I then shift into top gear and begin my sprint. I am a large guy at 6'4" and 200 lbs. I have found this to be the most efficiant for me. I know this is not the traditional way to do this. I can however produce great power in this gear and usually have a good result. I have looked over my front chain rings and do see a good bit of wear on the big ring. I am going to replace it and see what I get. The last time this happened I rode the whole day in the small front. I started to decend a hill and switched to large ring to push down the hill. when i reached the bottom I stayed seated for a bit. Then I wanted to put the power down and work hard to the finish. So i stood and started to push hard the chain made 2 revolutions before i Heard the pop of the chain and then no tension on the chain. Needless to say i tried to gather myself up but in the end went down. I think the front big ring needs to be replaced.

 

[alfeng]

I usually start out in a lower gear and ramp up the pace. I then shift into top gear and begin my sprint. I am a large guy at 6'4" and 200 lbs. I have found this to be the most efficiant for me. I know this is not the traditional way to do this. I can however produce great power in this gear and usually have a good result. I have looked over my front chain rings and do see a good bit of wear on the big ring. I am going to replace it and see what I get. The last time this happened I rode the whole day in the small front. I started to decend a hill and switched to large ring to push down the hill. when i reached the bottom I stayed seated for a bit. Then I wanted to put the power down and work hard to the finish. So i stood and started to push hard the chain made 2 revolutions before i Heard the pop of the chain and then no tension on the chain. Needless to say i tried to gather myself up but in the end went down. I think the front big ring needs to be replaced.

Okay, understood.

BTW. What is your smallest cog -- 12t or 11t?

If it is only a 12t, then consider re-stacking your cassette with an 11t as the smallest so that when you are "sprinting" on the 12t you will have a slightly better chainline.

I presume the chain is coming off the chainring on the inside. Is that right?

While it is probably less-than-desirable, consider removing the insert (does Campagnolo still use one for their recent 10-speed front derailleurs?) on the inside of the front derailleur cage so the outer plate is a bit further offset from the chain after shifting (if there isn't an insert, try a 9-speed front derailleur -- you'll probably need an extra "click" to move the derailleur from ring-to-ring, but that isn't a big deal, IMO) ... I have a sense that for some reason there is some lateral movement in your crank, and the front derailleur may possibly be bumping against the chain [also, be sure that there are a 2-to-3 millimeters VISIBLE between the top of the large chainring's teeth & the bottom edge of the front derailleur's outer plate] ... perhaps, not.

BTW2. I presume you are using a "standard" crank with a 135BCD (or, 130BCD). Is that right, too?

 

[kweil]

yes you are right it is a 12t. I am using standard record crank with 53/39 gear. the rear is a 12/25 cassett. I see that when in small rear 12t and large front 53t that the chain angle is not optimal. the chain is much straighter in the next position which happens to be a 13t cog. should i replace the 13t with the 12 and put a 11 in place where the 12 used to be? Then adjust the front derailur to have the gap which you mentioned.

 

[alfeng]

yes you are right it is a 12t. I am using standard record crank with 53/39 gear. the rear is a 12/25 cassett. I see that when in small rear 12t and large front 53t that the chain angle is not optimal. the chain is much straighter in the next position which happens to be a 13t cog. should i replace the 13t with the 12 and put a 11 in place where the 12 used to be? Then adjust the front derailur to have the gap which you mentioned.

Yes, if it isn't too inconvenient/expensive acquiring an 11t cog, that's what I would try in order to get your "sprinting" cog in a better alignment with your large chainring. Of course, there is NO ASSURANCE that this-alone will remedy the problem ...

BTW. If you do opt for restacking, just be sure you spec the proper cog because several years ago, when I restacked a 12-23 (9-speed Chorus cassette) to an 11-26 [NOT for sprinting!] I chose to use an 11t cog that I already had (don't ask me why I had it ... just something I picked up along the way!) which was intended for an 8-speed stack ... consequently, I had to narrow its integrated spacer. Presuming you have a 10-speed cassette, it would be best to simply buy a replacement 11t cog intended for a 10-speed cassette.

Whether you eliminate the 13t or another cog from the stack depends on your gearing preference.

Another option, which some might think is dodgy, is to switch to a 111mm BB (I'm presuming you have a non-UltraTorque crank) that is intended for triple cranks to move the chainrings outward from the bike's centerline by ~4.5mm. ADJUST YOUR CLEATS, ACCORDINGLY, IF YOU OPT FOR A LONGER BB SPINDLE ... if Q-factor is important to you (a few millimeters doesn't seem to bother me, personally ... think how much wider the pedals are on a mountain bike cranks!), that is.