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-   -   Dropouts not parallel (https://www.bikeforums.net/bicycle-mechanics/1141586-dropouts-not-parallel.html)

TakingMyTime 04-19-18 07:56 AM

They are Aluminum. As stated above, I've been able to get acceptable alignment with very light filing. I am happy with the result and I'm in the process of adjusting and tuning the drive systems.

I'd like to thank everyone for their input.

Kontact 04-19-18 08:40 AM


Originally Posted by HillRider (Post 20293701)
Are the dropouts aluminum? Many carbon frames have carbon dropouts too. If they really are aluminum, by all means file away.

FYI, there weren't any carbon dropouts back when Trek called their molded carbon race bike "5200". I believe the first bike with carbon dropouts wasn't until Look did it in 2007 or so and the 5200 ran between 1992 and 2006, even though the replacement "Madone" series (also with alloy dropouts) came out in 2003.

Koyote 04-19-18 09:46 AM


Originally Posted by Marcus_Ti (Post 20292807)
Take a frame alignment guage to it. Could be asymmetrical stays. Is the wheel actually off-axis to the centerline of the bike? Or is the stay spacing the only bug?

This is what I was wondering.

Trakhak 04-19-18 10:16 AM


Originally Posted by mrrabbit (Post 20293360)
. . . . when trouble shooting frames:

1. Properly dished wheels.
2. Dropout alignment.
3. Frame alignment check / Fork alignment check.
4. Then elsewhere....including fixes.

Jumping to #4 without any dead obvious "wrecked exotics" like damage / oddities is not how you go about stuff like this.

=8-P

Agree on all points.

Trek did very extensive R&D before they started selling the 5000 series carbon bikes. I never saw a single one misaligned in the years that I was running a store in those days that sold Treks. And, as Kontact noted, carbon bikes can crack or break, but it's almost impossible for them to bend.

Also, the OP mentioned that his wheels had needed extensive work. Some (inexperienced or overworked or lazy) mechanics have been known to true wheels without checking the dish. The rear wheel could also be a replacement, possibly with a larger OLD measurement.

OP: did you try putting the rear wheel in backwards (to check whether the rim would then be offset to the other side, which would indicate that the wheel was incorrectly dished) before you filed the dropout?

Reynolds 04-19-18 10:46 AM

I would get a long (40") 3/8" threaded rod with nuts and washers and use it to check dropout alignment. If you attach the rod at one end through both droputs you can check if it's perpendicular to top tube, the long rod magnifies any misalignment.

Marcus_Ti 04-19-18 10:48 AM


Originally Posted by TakingMyTime (Post 20293726)
They are Aluminum. As stated above, I've been able to get acceptable alignment with very light filing. I am happy with the result and I'm in the process of adjusting and tuning the drive systems.

I'd like to thank everyone for their input.


Well you did it...try riding no-hands and see if it wants to hold a line. That'll tell you if it was actually misaligned, or just the design of the frame.

Kontact 04-19-18 11:29 AM


Originally Posted by Marcus_Ti (Post 20294137)
Well you did it...try riding no-hands and see if it wants to hold a line. That'll tell you if it was actually misaligned, or just the design of the frame.

I would bet that most people would be able to detect a lack of line holding with their wheel cocked in the dropouts by a degree or two.

Anyone with horizontal dropouts can perform an easy experiment.

Reynolds 04-19-18 12:12 PM

You can also wet the tires to see how they track.

Kontact 04-19-18 12:56 PM


Originally Posted by mrrabbit (Post 20293360)
Who knows, maybe all his wheels are zero dish wheels (which of course do not exist for symmetrical frame based bikes which 99.99% of us ride.)

I kinda wonder too if the frame in question has a bond that has come loose or slipped. I've seen it happen on a late 90s Vitus? - and you couldn't tell with a cursory look cause it somehow looked clean even when slipped. (Left chainstay into dropout.)

Either way - when trouble shooting frames:

1. Properly dished wheels.
2. Dropout alignment.
3. Frame alignment check / Fork alignment check.
4. Then elsewhere....including fixes.

Jumping to #4 without any dead obvious "wrecked exotics" like damage / oddities is not how you go about stuff like this.

=8-P

Why would these theoretical zero-dish wheels put the rim closer to the drive side stay?

How would dropout alignment cause this, and what would be the correct fix other than filing on an aluminum/carbon frame?

mrrabbit 04-19-18 02:03 PM


Originally Posted by Kontact (Post 20294466)
Why would these theoretical zero-dish wheels put the rim closer to the drive side stay?

How would dropout alignment cause this, and what would be the correct fix other than filing on an aluminum/carbon frame?

Would be left stay actually....

Aluminum dropouts can get bent out of alignment....enough to cause a few mm's of off wheel positioning.

But again....usually when these kinds of frames come out of the factory - they are already properly aligned.

Which is why I also wondered if a bond has come loose - either now or has in the past with this frame.

Would be nice if the OP would post some pics.

=8-P

Kontact 04-19-18 04:17 PM


Originally Posted by mrrabbit (Post 20294607)
Would be left stay actually....

Aluminum dropouts can get bent out of alignment....enough to cause a few mm's of off wheel positioning.

But again....usually when these kinds of frames come out of the factory - they are already properly aligned.

Which is why I also wondered if a bond has come loose - either now or has in the past with this frame.

Would be nice if the OP would post some pics.

=8-P

Right. But the OP said that the rim is close the right stay, not left.

I don't see how a mis-aligned dropout could move the whole wheel, but if it did, how would you want to correct it in a bonded frame? A file seem like a good way to not abuse the bond.


But if a bond did come loose, there's no fixing it.

mrrabbit 04-19-18 04:32 PM


Originally Posted by Kontact (Post 20294864)
Right. But the OP said that the rim is close the right stay, not left.

I don't see how a mis-aligned dropout could move the whole wheel, but if it did, how would you want to correct it in a bonded frame? A file seem like a good way to not abuse the bond.


But if a bond did come loose, there's no fixing it.

Wrong...

Vitus Aluminum and Carbon frames using "screwed and glued" and simple "insert and glue" tech would experience joint separation on occasion.

For the Aluminum models, typically did not happen at the three main tubes as they were screwed and "glued".

Typically, separation would occur between drive or non drive chaintstay and the rear dropouts.

Easy fix, could be done locally or sent into Vitus.

Clean, prime, apply glue, reinsert the tube - hold in jig for proper alignment while the glue set.

Quite a few other manufactures copied Vitus on this late 80s to late 90s tech.

If memory serves me correctly, also used in Looks, certain model year Raleighs and by Trek as well.



https://groups.google.com/forum/#!to...ob/OAKK3Q4NTBE


=8-)

Kontact 04-19-18 04:43 PM


Originally Posted by mrrabbit (Post 20294899)
Wrong...

Vitus Aluminum and Carbon frames using "screwed and glued" and simple "insert and glue" tech would experience joint separation on occasion.

For the Aluminum models, typically did not happen at the three main tubes as they were screwed and "glued".

Typically, separation would occur between drive or non drive chaintstay and the rear dropouts.

Easy fix, could be done locally or sent into Vitus.

Clean, prime, apply glue, reinsert the tube - hold in jig for proper alignment while the glue set.

Quite a few other manufactures copied Vitus on this late 80s to late 90s tech.

If memory serves me correctly, also used in Looks, certain model year Raleighs and by Trek as well.



https://groups.google.com/forum/#!to...ob/OAKK3Q4NTBE


=8-)

What do you mean, "wrong"? This is a carbon bike, not an all aluminum Vitus or Trek 1200. Bond failures between carbon and aluminum components are generally considered un-repairable because of the nature of the bond between composites and metals. Repair places like Calfee won't even attempt them.

Bond failures on Vitus frames were generally from poor bonding and glue sheer between two aluminum pieces.

mrrabbit 04-19-18 04:55 PM


Originally Posted by Kontact (Post 20294934)
What do you mean, "wrong"? This is a carbon bike, not an all aluminum Vitus or Trek 1200. Bond failures between carbon and aluminum components are generally considered un-repairable because of the nature of the bond between composites and metals. Repair places like Calfee won't even attempt them.

Bond failures on Vitus frames were generally from poor bonding and glue sheer between two aluminum pieces.

Depends upon the manufacture....old Peugeots (1980-83) using bonded carbon and aluminum could be repaired...costly though. Only saw two in the SF Bay in my 40 years here, 1 got repaired under warranty. Owner never liked the bike. They're rare are teeth on a hen.

As I stated earlier - wish the OP would post some pics. I want to see the make, model and closeups of the bottom bracket assembly, rear dropout assemblies - and the wheel in question.

=8-)

mrrabbit 04-19-18 04:59 PM

Pulled up the data on this Trek 5200...I definitely want to see closeup pics...something is wrong here.

=8-)

Kontact 04-19-18 05:30 PM


Originally Posted by mrrabbit (Post 20294965)
Pulled up the data on this Trek 5200...I definitely want to see closeup pics...something is wrong here.

=8-)

This is what the dropouts for these bikes looked like:

https://farm8.staticflickr.com/7470/...e14c7b8e_b.jpg

These "OCLV" frames were assembled out of pressure molded components in a jig. All that has to happen to get a bike like the OP's is for the assembly worker to not seat the right dropout fully into the jig, since all the joints are overlapping tapered slip fits rather than squarely butted. The right dropout is only off by less than 2mm.

mrrabbit 04-19-18 05:48 PM


Originally Posted by Kontact (Post 20295014)
This is what the dropouts for these bikes looked like:

https://farm8.staticflickr.com/7470/...e14c7b8e_b.jpg

These "OCLV" frames were assembled out of pressure molded components in a jig. All that has to happen to get a bike like the OP's is for the assembly worker to not seat the right dropout fully into the jig, since all the joints are overlapping tapered slip fits rather than squarely butted. The right dropout is only off by less than 2mm.

As I stated very clearly, I pulled up the data....

That's not the OPs bike....that's the exact same photo I pulled up from Google Images.

I want to see pics of HIS / HER frame.

=8-P

Kontact 04-19-18 06:00 PM


Originally Posted by mrrabbit (Post 20295057)
As I stated very clearly, I pulled up the data....

That's not the OPs bike....that's the exact same photo I pulled up from Google Images.

I want to see pics of HIS / HER frame.

=8-P

Ididn't say this was the OP's bike, I said this is the what all 5200/5500 dropouts looked like, and a notable feature is how they don't have a shoulder that the chainstay butts up against to visually gauge insertion depth.


Again, generalities vs specifics.


Could the OP's dropout have become de-bonded? Sure. But TREK was aware of galvanic corrosion issues at aluminum bonding points and used fiberglass to electrically isolate the components, so that type of failure is rare for Treks compared to Colnagos. And the OP would have to have missed the dropout moving every time he tried a new wheel in the frame and tugged it back into position.

mrrabbit 04-19-18 06:07 PM


Originally Posted by Kontact (Post 20295072)
Ididn't say this was the OP's bike, I said this is the what all 5200/5500 dropouts looked like, and a notable feature is how they don't have a shoulder that the chainstay butts up against to visually gauge insertion depth.


Again, generalities vs specifics.


Could the OP's dropout have become de-bonded? Sure. But TREK was aware of galvanic corrosion issues at aluminum bonding points and used fiberglass to electrically isolate the components, so that type of failure is rare for Treks compared to Colnagos. And the OP would have to have missed the dropout moving every time he tried a new wheel in the frame and tugged it back into position.

Generalities AND Specifics...and a multitude of possibilities.

...of which neither do we have photo evidence of from OP. Just his words/statements. Yet you keep coming back at me even though I'm kinda holding off on further judgement until we see an update.

Trying to "win" something?

=8-)

Kontact 04-19-18 07:47 PM


Originally Posted by mrrabbit (Post 20295079)
Generalities AND Specifics...and a multitude of possibilities.

...of which neither do we have photo evidence of from OP. Just his words/statements. Yet you keep coming back at me even though I'm kinda holding off on further judgement until we see an update.

Trying to "win" something?

=8-)

The OP sent me a few PMs, and the frame and dropout bonds were thoroughly examined.

I was just trying to point out to you that the shape of the dropouts is not going to make a bond failure visible since they don't have a shoulder and aren't susceptible to galvanic corrosion. So I'm not sure what a photo would tell you, but it doesn't sound like the OP is interested in satisfying you.

Andrew R Stewart 04-19-18 08:21 PM

Here's a couple of data points WRT fixing bonded carbon to AL.


I have followed Kuota's verbal instructions to clean and rebond a seat stay to a LH drop out. The epoxy was their recommendation (one of two choices they speced, bought in a local hardware store. I chose the slower curing version (my ski repair experience guided my choice in wanting a longer wet period to set the alignment during) I used a good rear wheel to establish the vertical alignment, blocks held the wheel within the stays equally (the QR was only snugged as to not change the drop out's original verticalness, or lack of). This was in 2011 and the bike was tuned up last year bu our shop, still in one piece.


I have also watched as a carbon frame had it's brake bridge rebonded onto one stay. Wish I could remember the brand but the bridge was a machined AL affair, kind of clunky with it's attempt at more surface area contact with the stays (didn't help on the bad side:)). Again my friend pulled the stay back from the bridge, cleaned with solvent (acetone I think by the smell), applied epoxy and toe strapped the stay against the bridge. Again a few years later the bike was still solid.


The first bike bonding failure I remember seeing was when I was taking Eisentraut's class in Rutland (1979) on an AL to AL fork drop out. I don't know what was done with that one but Al expressed both the reapirability as well as that she (the rider) should have gotten a steel bike instead.


In my two stints in the retail ski service business (mid 1970s and mid 1980s) we repaired many skis made of various materials (fiber glass and I thing carbon fibers) that used steel edges and AL binding retention plates. These were usually done with the understanding the repairs were not a life long solution. But I do know of at least a couple pairs of skis repaired by us that were handed down to the kids a season or two later. Andy

mrrabbit 04-19-18 08:26 PM


Originally Posted by Kontact (Post 20295248)
The OP sent me a few PMs, and the frame and dropout bonds were thoroughly examined.

I was just trying to point out to you that the shape of the dropouts is not going to make a bond failure visible since they don't have a shoulder and aren't susceptible to galvanic corrosion. So I'm not sure what a photo would tell you, but it doesn't sound like the OP is interested in satisfying you.

As we have often said here on Bikeforums, especially in the infamous Mozzy versus Ride Tommasini thread:

"Crap or get off the toilet."

=8-)

Kontact 04-19-18 08:46 PM


Originally Posted by mrrabbit (Post 20295320)
As we have often said here on Bikeforums, especially in the infamous Mozzy versus Ride Tommasini thread:

"Crap or get off the toilet."

=8-)

I don't think every thread starter is obliged to jump through hoops for any poster that demands a picture or wants their opinion acknowledged. Especially posters that largely ignore the information already posted in the thread. THe OP sounds VERY thorough in his inspection of his frame and in trying multiple wheels.

If you believe there is some avenue left unexplored, you should point to what it could be rather than imply that withholding a photo from you is some sort of cover up.


If this was a metal frame or hadn't been closely inspected already there would be more to check or other solutions to consider. But the fact that this bike consists of small pieces of aluminum glued decades ago into unbendable carbon tubing limits what can be done without causing damage. Minorly truing up the dropouts with a file accomplishes what the OP needs without extra inspections that won't yield solutions - it doesn't matter if the whole frame is crooked if you can't fix a crooked CF frame or the dropouts can't be bent without straining the bonds.

70sSanO 04-19-18 09:28 PM


Originally Posted by TakingMyTime (Post 20293726)
They are Aluminum. As stated above, I've been able to get acceptable alignment with very light filing. I am happy with the result and I'm in the process of adjusting and tuning the drive systems.

I'd like to thank everyone for their input.

I thought this had ended the thread. Unless the dropouts are loose or have failed, does it matter how the assembly was done on a 15+ year old? Some of this discussion is interesting, some is just a contest. Maybe interviewing the Trek employee who made the frame would help.

John

Andrew R Stewart 04-19-18 10:30 PM

Real life does things to theory, speculations or hope. When I read people saying that a jig insures alignment and I see frequently enough misaligned carbon/bonded frames I have to side on what I see. I've seen many minor wheel sitting "offnesses" on many brands and types of bikes (mostly road as they comprise most of the carbon built bikes I've worked with), both forks and rear ends. The tight clearances of TT bikes have been especially prone to power induced tire rubs when this off center wheel stuff happens. I have shifted the dish of a few wheels to compensate, not the best solution but sometimes you do what you need to. I have filed quite a few drop outs, mostly on forks, to allow the wheel to center at the brake/crown/stays.

This is rather interesting to me as a many year "gentleman builder" and also as a front line shop wrench. What I do in a LBS isn't always what I am happy with at home in my own shop. For years I have wondered about carbon frame alignment, seeing what I see and knowing what I do about steel frames. I've never bothered to pursue carbon frame tolerances in a setting where real numbers are found. But this thread has me rethinking my lack of motivation to measure carbon frames on my flat surface and use the same methods of testing I apply to my own (and other's) steel frames. (Why take time when I had no interest in trying to make one and also knowing that any corrections are limited?) So I have a new project that I'll follow up on in my own sweet time. At some point, likely this fall, I'll do some checking on whatever carbon frames I can come across (and take home for a while) and post back. Andy


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