Classic & Vintage - Drivetrain Help (Please Help me...)

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




ridethecliche
03-11-08, 09:52 PM
I figure a bunch of you toy around with builds and mix and match componentry so you might be able to help me out. Thanks in advance.

Background:
I worked my ass off to get together the money for a build I just finished. It's an 84 trek 760 and it has a mixed drivetrain. The front der is the original suntour superbe, the rd is a veloce, the shifters and cranks are campy centaur (compact crank), and the chain and cassette are shimano 105. I know it's a real crazy mix of components, but I put it all together about 2 weeks ago and it all worked really well. The LBS was amazed that the shimano spacing could be made to work and I was just thrilled that it all worked well enough to ride.

I raced the bike this past weekend and it didn't mis shift and let me down at all. It was a blast to ride and I was glad to be able to leave my cannondale at home since the weather was going to be nasty and I didn't want to end up crashing the bike (it was my first race).

I went out for a 25 mile ride on the bike yesterday and everything was working fine.

The Problem:
The problems started today, I set the bike up on the trainer and was spinning pretty easily. I was in the middle of the cassette and I decided to shift down to the smaller chainring. All of a sudden, there's no tension in the chain anymore. The chain is just gliding on top of the small chainring and it refuses to go onto the small chainring. If I shift up and down a few times from the big ring to the small ring, it'll eventually fall into place, but it was NEVER like this before. It just 'glides' or 'skates' over the small chainring and refuses to drop onto the small chainring...

While trying to do this, the chain not only dropped onto the bb off the small chainring, it also fell off the big ring and scratched the crap outta the finish of my cranks... I understand that I can drop my chain if I'm really badly crosschained and I shift in the front, but I have no idea how to fix this problem.

I'm really distraught about this and I honestly can't figure out what's going on.

Please help me out?

Thanks in advance.


ridethecliche
03-11-08, 09:56 PM
It looks like the chain gets stuck between chainrings if I shift when on the middle cogs of the cassette, I guess this might make sense because of the angle of the chain, but the chain is a 10 speed 105 chain and the cranks are 10 speed also, as campy has been 10 speed forever...

Is a 10 speed campy chain much wider than a shimano one?

For now I guess I'm just going to have to mind my shifting habits and shift in the back before shifting in the front to avoid this happening.

Would it be possible to use a triple FD and lock out the limit screws so I don't throw the chain onto the frame? If I need a new fd, that might be the cheapest way to go about finding a working solution. An older shimano or campy clamp on FD?

Any ideas?

Road Fan
03-11-08, 10:05 PM
It looks like the chain gets stuck between chainrings if I shift when on the middle cogs of the cassette, I guess this might make sense because of the angle of the chain, but the chain is a 10 speed 105 chain and the cranks are 10 speed also, as campy has been 10 speed forever...

Is a 10 speed campy chain much wider than a shimano one?

For now I guess I'm just going to have to mind my shifting habits and shift in the back before shifting in the front to avoid this happening.

Would it be possible to use a triple FD and lock out the limit screws so I don't throw the chain onto the frame? If I need a new fd, that might be the cheapest way to go about finding a working solution. An older shimano or campy clamp on FD?

Any ideas?

Before you think about more parts, I'd go back through the cable and derailleur settings and make sure the front derailleur travel is limited the right way. Usually overshifting off the chainring is due to the cage moving too far. This problem can be present on the front and rear derailleurs, and on both the inner and outer limits.


int19
03-12-08, 12:30 AM
Hi there,

Is your chain too long? That's the first thing I thought of.

http://www.parktool.com/repair/readhowto.asp?id=26

ridethecliche
03-12-08, 06:09 AM
Before you think about more parts, I'd go back through the cable and derailleur settings and make sure the front derailleur travel is limited the right way. Usually overshifting off the chainring is due to the cage moving too far. This problem can be present on the front and rear derailleurs, and on both the inner and outer limits.

That would explain going over the big ring, but not the inability to shift onto the small ring. The limit for the small ring is set to go as much as possible and it still doesn't shift into the small ring all the time. The limit screw is set so the FD can move as much as possible when it's shifting down to the small ring.

ridethecliche
03-12-08, 06:14 AM
Hi there,

Is your chain too long? That's the first thing I thought of.

http://www.parktool.com/repair/readhowto.asp?id=26

I used their method to set up the chain. Big ring, big cog, 1 extra link. Done.

I don't think it's the chain length that's the problem.

ridethecliche
03-12-08, 06:50 AM
Could I lock out the limit screws and possibly use a triple fd to get the little bit of extra movement I might need? The superbe FD might not have the range of motion to shift a 50/34 100% of the time.

Thanks for the input!

splytz1
03-12-08, 07:09 AM
Just a thought - did you get your allen keys out to make sure all your chainring bolts are tightened to spec? I'm just wondering if yesterday's ride might have loosened a chainring bolt or two, causing your setup to become slightly off-parallel and incurring shifting problems.

JunkYardBike
03-12-08, 07:31 AM
Is your derailleur hanger (on the frame) bent? If you eye your RD from the rear, is the pulley cage lining up more or less parallel with the cassette? Is it skewed toward either the driveside or the non-driveside?

On the FD, you may just have to tweak it a bit, toe in or toe out...

USAZorro
03-12-08, 07:45 AM
...On the FD, you may just have to tweak it a bit, toe in or toe out...

I think this is likely. I had to monkey around with the toe-in and limits to get my 760 to shift properly onto the small ring. I think the modern spindles may be a little longer than what was used in 1984, which could cause what we've both seen.

WNG
03-12-08, 08:13 AM
I suspect the Superbe FD is too wide. Its cage is spaced for a 7 speed chain and chainrings.
There's probably a big enough gap to allow the chain to drop off the rings.
You can try to pinch the cage narrower, and replace the spacer between the plates with something a few millimeters shorter. A nylon lift-off for motherboards come to mind. Or a series of small flat washers.

As for chain length, it can still be too long...as you mentioned it seemed to not have enough tension to force the chain to engage the small chainring.
I'd check to see if the pulley cage has enough pull on the chain while you're in the small cog/small chainring combo. You are running a compact crank.

ridethecliche
03-12-08, 08:16 AM
Well my limit for the FD for the small chainring is as far as it'll go. I'll mess with the toe in, though I tried that and it got to the point where it wouldn't shift up to the bigger chainring, though I could adjust the limit screw here to get that to work.

I'm so bummed about the finish on the crank, it's all marred up now though I guess it could be a lot worse...

I'll get my RD hanger looked at. I think I might have cross threaded the RD when I was putting it in and this could have caused the problems on the back as far as the chain shifting onto the dropouts which are now marred as well...
If I adjust the RD limit screws, it doesn't shift onto the small cog. I'll take it to the lbs to have them look at the RD hanger alignment and chase the threads on the RD, though they'd told me not to worry about it if it was shifting, which it is. I'll look into doing that in a bit though, when I have a little more money to spend on bike stuff.

Thanks for the help everyone. I'll toe in the FD and adjust the limits to see if that helps. I'll do it in the afternoon possibly since I want the time to be able to run to the LBS if I just want to give up haha. I'll let you guys know how it goes.

As an additional question: Would a triple FD work? Could I adjust the limits enough for it not to throw a chain on a double? I could just use that if this doesn't work.

Also, if the RD shifting works, should I still get the threads chased and the RD aligned?

Thanks again.

ridethecliche
03-12-08, 08:19 AM
I suspect the Superbe FD is too wide. Its cage is spaced for a 7 speed chain and chainrings.
There's probably a big enough gap to allow the chain to drop off the rings.
You can try to pinch the cage narrower, and replace the spacer between the plates with something a few millimeters shorter. A nylon lift-off for motherboards come to mind. Or a series of small flat washers.

As for chain length, it can still be too long...as you mentioned it seemed to not have enough tension to force the chain to engage the small chainring.
I'd check to see if the pulley cage has enough pull on the chain while you're in the small cog/small chainring combo. You are running a compact crank.

If the chain gets stuck in the space between the big and small chainring, is that still a tension problem in your opinion?

Thanks.

USAZorro
03-12-08, 08:21 AM
fyi - when adjusting the toe - a mm can make all the difference - as can the height. On the height, the FD should be able to clear the large ring by no more than 1/4" when you shift to the big ring.

ridethecliche
03-12-08, 08:55 AM
fyi - when adjusting the toe - a mm can make all the difference - as can the height. On the height, the FD should be able to clear the large ring by no more than 1/4" when you shift to the big ring.

I used a penny to determine the clearance of the fd on the big ring.

I'll play with the toe in today. I'm really hoping that's all it needs...

WNG
03-12-08, 12:05 PM
Is this a 10 spd Centaur crank? I find it odd that the 10-spd chain would fit in between the chainrings.
Maybe a 9 spd spacing?
This is a different matter from the chain skating on top of the chainring. Not enough tension can still cause this as there should be enough tug to cause the teeth to wrap the chain onto the ring.

g-funk
03-12-08, 12:13 PM
I don't think the triple FD will solve anything. if your chain can easily fit between the big and little chainring this is a problem. are your shifters and crank set up for the same spacing?

edit: I just saw your signature, put that superbe stuff back on!

justinb
03-12-08, 12:18 PM
I hope this doesn't confuse the issue too much, but my Campy 50/34 setup has a compact-specific front dérailleur, and shifts much better than another bike that has a compact crank but a dérailleur intended for a 53-39 8 speed system.

lotek
03-12-08, 12:34 PM
The superbe was some pretty race specific componentry and as such was limited in what it
could handle. I wonder if the FD just won't handle the drop from 50 to 34, remember the
usual setup back in the day was 42 52 nothing like a 16 tooth difference.
I'd start looking at a Centaur Compact FD.
and yah, I agree with g-Funk put the superbe back on it.
marty

edit looked up superbe capacity and it is either 16T or 18T, so I stand corrected. It should
handle the difference. That said I stand by my statement of either put a centaur compact
or all the superbe back on.

marty

ridethecliche
03-12-08, 01:05 PM
I don't think the triple FD will solve anything. if your chain can easily fit between the big and little chainring this is a problem. are your shifters and crank set up for the same spacing?

edit: I just saw your signature, put that superbe stuff back on!

I'd love to put the superbe stuff back on, but I can't do hill rides on a 52/42. That's why I started swapping things in the first place.

I bought the crankset from performance and its a 10 speed setup. I think the chainring bolts might have worked themselves loose. I'll tighten them up and see what that changes.

ridethecliche
03-12-08, 01:11 PM
With all due respect to every one of you awesome C&V'ers, I loved the bike the way it was built, but it doesn't fit my needs for a training/backup race bike with the superbe stuff on it. The 52/42 is a little extreme gearing for hill rides and the spacing doesn't work out well with a 13-28 cassette or the like. I have to admit that I'd love to put the superbe brakes on there because, face it, they'd look a lot better AND be lighter than the centaur brakes. However, they don't work as well as dual pivots and having better brakes is more important to me than having lighter brakes.

How I wish that the campy brakes looked that sweet though :(

I love the parts and I love the frame, but the superbe parts just weren't what I needed on this build. I can't have downtube shifters and a 52/42 on this bike because I can't handle that gearing. It works fine.

If you like the stuff, buy it, it's for sale ;)

I posted this question here because a bunch of the regulars on this forum do put the newer campy parts on some nice older frames and I thought that the mix and match componentry, old and new, would have some people interested in either seeing what was going on and or helping out, which has been the case.

Thanks for all your help.

Like I said, I'm going to try tightening the chainring bolts and see how that works out. It could decrease the spacing difference if the bolts worked themselves loose. I hope it works!

g-funk
03-12-08, 03:24 PM
just giving you a hard time about the superbe stuff, but where do you live where you can't hang with a 42-28? Maybe when you build up your strength with all your racing you can push bigger gears and then go back to the superbe components. I'm an italian bike nut and think that the suntour components were the best, simplest components made. I think your best bet would be to buy a campy 10speed front d and play with that, if the chainring bolts don't work. There's a reason that bikes don't typically come set-up with mismatched parts.

bigbossman
03-12-08, 03:42 PM
just giving you a hard time about the superbe stuff, but where do you live where you can't hang with a 42-28? Maybe when you build up your strength with all your racing you can push bigger gears and then go back to the superbe components.

Not directed at you personally (because I think you live somwhere here in the Bay Area:)), but I really get tired of hearing this. Not everyone lives in Florida or Kansas where freeway overpasses count for climbs - some of us have to deal with protracted, respectable climbs every time we go out. Coupled with the fact that some of us (me, for example :)) are about as strong a rider as we're ever gonna be. I'm not going to "get stronger" by mashing a ridiculous gear combo for my environment, but I might well ruin my aging knees. No, thanks.

RTC - you once asked me if the vintage Suntour Superbe stuff would work with the modern Campy 10 speed stuff, and the best I could offer you was "try it and see". Looks like you did, and it doesn't. Mix 'n match doesn't work great with the newer stuff, and you're not getting the full potential of the performance it has to offer when you try it. Go to eBay, get the proper Veloce/Centaur FD for ~$25, and be happy.

If the chain is falling between the rings then the chain is too narrow, the chainring gap is too large, or the FD is too wide for the chain and is allowing sloppy shifts - with poor and unpredictable results.

g-funk
03-12-08, 03:57 PM
Not directed at you personally (because I think you live somwhere here in the Bay Area:)), but I really get tired of hearing this. Not everyone lives in Florida or Kansas where freeway overpasses count for climbs - some of us have to deal with protracted, respectable climbs every time we go out. Coupled with the fact that some of us (me, for example :)) are about as strong a rider as we're ever gonna be. I'm not going to "get stronger" by mashing a ridiculous gear combo for my environment, but I might well ruin my aging knees. No, thanks.

I live in Santa Rosa. This was a tongue in cheek comment and wasn't meant for everyone it was meant for our compatriot RTC who is actively racing his bike and going on training rides, these training rides are designed to make you a stronger cyclist. Stronger cyclists push bigger gears. I, like you BBM, go on bike rides, not training rides :D


Go to eBay, get the proper Veloce/Centaur FD for ~$25, and be happy.


well said.

cyclotoine
03-12-08, 03:58 PM
Seems really odd that the chain is dropping between rings (is the inner ring installed backwards?). But I will add my voice to the chorus and say get a compact FD. I had a regular centaur 10 speed double on my bike with the correct FD and when I switched to compact I didn't even mess around I went down to the LBS and bought the century grey compact FD to match. Even still it doesn't shift great. I should actually try tweaking it before the next ride.

ridethecliche
03-12-08, 09:19 PM
G-funk, I live in CT and love riding hills while I'm not all that great at them. I built this bike up as a training bike/easy bike. I have a 53/39 equipped cannondale CAAD9 for races in good conditions. I really like the frame and I actually wanted to use it so I built it up with stuff that I knew I could enjoy it with. I'm sorry about being snarky earlier, but it hasn't been the best day. First this happens, then I spend 11 hours in lab trying to purify proteins with no results... So, I'm sorry for being a little short fused earlier.

I love the superbe stuff, I honestly do, but I just can't climb well with it. I do a training ride that's 16 miles long with over 1600 feet of climbing, with the majority of that in 7 miles. The rest of the ride is just getting to the hills and back. I can't do that on a 42-26. More power to the people that can.

To everyone (including g-funk) who said go the ebay route and get a compact campy fd, thanks for the suggestion. I'm just going to get the new FD. That should sort everything out, hopefully. Turns out that the campy chain is narrower than the shimano chain I'm using so that can't be to blame. Unfortunately, there are no compact campy FD's on ebay right now.

I checked pbk and they don't have any compact fd's for sale. It turns out that the 2008 campy FD's are 'combined' with functionality for both doubles and compacts. Would this be a wise choice, or should I just look elsewhere for a compact veloce FD and a correct braze on adapter. I'm guessing my frame has a 28.6 seat tube, is this logical considering it's a vintage trek with 531P tubing? So I should get this braze on adapter right? PBK doesn't have one, I'll see if the LBS does.

Here's the FD for sale at PBK it says combined for 2008 meaning that it should handle compact and regular doubles: Link (http://probikekit.com/display.php?code=L4041)

Here's a picture of what's going on with my crankset:
http://i179.photobucket.com/albums/w298/rtc247/Chaindrag.jpg

Thanks for the help guys. I'm bummed that this didn't work out, but it was a good learning experience. The compact FD should solve the problem above right?

g-funk
03-12-08, 09:51 PM
you should be able to get that derailleur at the bike shop pretty cheap. That chain doesn't look right though. Maybe get the lbs to lay a new campy chain in there when you are buying your front d. If it doesn't slip down like the shimano one, buy the chain too.

My guess is the campy chain won't work with the Shimano cassette next. But don't worry, I think Action Tec makes a Titanium Shimano freehub body to Campy index spacing cassette for like 856 bucks. I think the mechanic that told you everything would work together just fine lied to you.

ridethecliche
03-12-08, 09:51 PM
As an addendum, I'm going to add that the campy compact cranks are going to be mailed back to performance tomorrow for an exchange. They've been a bit marred by this experience and one of the bolts is stripped, so back they go and I should get a new set in a week or two from performance.

If you guys think it's the right part, then I'll order that 'combined' FD from PBK and go to the LBS for the braze on adapter.

Sound about right?

Thanks for all your help guys, I really really appreciate it. I was so excited about this build and I'm a little bummed now, but I'm looking forward to things working out well.

I'm just really glad this problem didn't start while I was racing over the weekend. That could have been disasterous...

ridethecliche
03-12-08, 09:54 PM
you should be able to get that derailleur at the bike shop pretty cheap. That chain doesn't look right though. Maybe get the lbs to lay a new campy chain in there when you are buying your front d. If it doesn't slip down like the shimano one, buy the chain too.

My guess is the campy chain won't work with the Shimano cassette next. But don't worry, I think Action Tec makes a Titanium Shimano freehub body to Campy index spacing cassette for like 856 bucks. I think the mechanic that told you everything would work together just fine lied to you.

I had a feeling that the chains might not be compatible so I checked the width of the chains. The shimano chain is a little wider than the campy ultra narrow 10 speed chain that pbk has so the chain should be just fine.

I think the next thing this bike is going to get is a campy rear wheel, cassette, and chain so I can put an end to this nightmare!

Edit: I would try taking it to the shop except that the crankset has already been pulled off in order for it to be sent to performance for an exchange.

As a side note, I just put my cannondale on the trainer and was instantly amazed at how weird I felt on it. Something just didn't feel right on the bike. I felt like I might have been too stretched out, I don't know, but the trek just felt so much more 'right'. This is messed up... Hahaha.

justinb
03-12-08, 10:09 PM
The Campy Ultra-Narrow 10 speed chain I had was awesome, but a pain to work with... special pin, everything else. Get the KMC version with a connecting link and you'll be much happier. I think Performance markets a KMC-made 10 speed chain as well; probably the same thing.

How's the rear indexing on your setup?

EDIT: I should add that the KMC version is much much less expensive as well; this is the primary reason I chose it.

cyclotoine
03-12-08, 10:40 PM
One of the bolts was stripped? You must have really wrenched them... are you sure that it wasn't just the whole crank bolt turning (i.e. you need the annoying crank bolt tool)? Did pbk say they would inspect the crank or are they going to replace without question. I hope you don't get a surprise and get the same crank back in the mail in a couple weeks.

ridethecliche
03-12-08, 10:52 PM
One of the bolts was stripped? You must have really wrenched them... are you sure that it wasn't just the whole crank bolt turning (i.e. you need the annoying crank bolt tool)? Did pbk say they would inspect the crank or are they going to replace without question. I hope you don't get a surprise and get the same crank back in the mail in a couple weeks.

It was performance, and I called and talked to a rep who told me that they'd just replace it if I wasn't happy. Replace they shall!

What do you make of the picture? Do you think the new FD will fix the problem? Do you think the 2008 'combined' fd should be fine or should I get the 07 compact?

Thanks!

ridethecliche
03-13-08, 07:51 AM
Does anyone have a clue as to what was going on with the chain in that picture?

My guess is that the FD wasn't quite throwing it far enough on the shift and it got stuck. Sometimes it would work, but the rest of the time it was a big 'FAIL!'.

WNG
03-13-08, 10:45 AM
What's odd is that the chain doesn't fall onto the teeth. As if the teeth are too wide or the chain too narrow.

Sorry I can't help you further, as my experience with mixing 7/8/9/10 spd equipment is limited, and I won't get more insight until I finish one of my builds mixing 8 spd chain and cassette, with 9/10 spd derailleurs and crankset.

ridethecliche
03-13-08, 04:56 PM
What's odd is that the chain doesn't fall onto the teeth. As if the teeth are too wide or the chain too narrow.

Sorry I can't help you further, as my experience with mixing 7/8/9/10 spd equipment is limited, and I won't get more insight until I finish one of my builds mixing 8 spd chain and cassette, with 9/10 spd derailleurs and crankset.

Thanks for the help that you could give though!

I sent the crank back to performance for an exchange for a new one and I ordered a new 08 veloce FD.

I think that should solve it, if not, then I'm going to look for the cable end that cracked a little when I was installing the cables. Though I'm not sure that was for the FD.

ridethecliche
03-30-08, 02:11 PM
Update:

New cranks- Check!
New Veloce FD and Braze on Clamp- Check!
Installed- Check!

Proper shifting- CHECK!!!

Yay!

It turns out that my cannondale is a frame size too small. The shop where I bought it offered to move me to a bigger frame at no cost. Till that happens, the trek is my main bike. I can't stand riding a bike that gives me lower back pain for any ride over 40 minutes!

That being said, I love the trek. Did a group ride with it yesterday and it felt amazing. It was funny, I kept up and led the pack with a group of riders who always drop me like a bad habit.

JunkYardBike
03-30-08, 03:09 PM
That being said, I love the trek. Did a group ride with it yesterday and it felt amazing. It was funny, I kept up and led the pack with a group of riders who always drop me like a bad habit.

See, steel is real!*





*But for some reason I don't get the same results. *gasp* *cough* *bonk*

ridethecliche
03-30-08, 03:20 PM
See, steel is real!*





*But for some reason I don't get the same results. *gasp* *cough* *bonk*

To be completely honest. I love how the bike rides. I built it up to be a bad weather/grimey conditions road bike but I like it more than my CAAD9. The big part of the reason is probably fit, because there's about a 4 lb weight difference between the two.

I'm going to take both bikes with me when I go to the lbs (which happens to be 3 hours away since I'm away at college) and see if they can set the cannondale up to mimic the trek.

The trek has more drop, but less reach and is more comfortable. I have no idea what's going on with the fit...