xseams and chain hitting derailler cage

[jeebus]

After getting lots of help from doug on putting my used silvio together, I rode my first few miles this evening.

It'll take some getting used to. It's clear my muscles are all fighting against one another and not working at all efficiently yet. But I'm looking forward to comparing it to my strada after I learn to ride it more effectively.

My biggest remaining technical challenge right now involves the chain hitting the derailler cage. I was aware that this would happen to short riders who try to use a granny gear, but I'm 5-10 and was in the middle chain ring.

Specifically I've got an ultegra setup where the cassette and chainring are 11,12,13,14,15,16,17,19,21,23 and 52-39-30. And I can't shift to a smaller gear than 19 without the chain hitting the cage (this while in the 39 front ring).

My xseam is 40-41 which might be a little low for my height. I think my thinness takes a couple inches off my xseam vs a lot of people my height. Anyway, at that xseam should I have this problem at such an early point? I thought ultegra was supposed to have one of the longer derailler cages.

Deraillers confuse me, but are there any adjustments that might help with this?

- Mark

UPDATE: problem solved by connecting the front derailler to the correct two mount holes (the lower set that I didn't realize were there at first).

 

[Mark B]

This is probably a silly question, but are you sure you are using the correct set of derailleur mounting holes? You should be using the "southern-most" holes; the ones closest to the center of the TFT.

Mark

 

[Mark B]

jeebus wrote: It'll take some getting used to. It's clear my muscles are all fighting against one another and not working at all efficiently yet. But I'm looking forward to comparing it to my strada after I learn to ride it more effectively. -

I'll be interested to read your thoughts.... Before I bought my Silvio, all I had to compare was my conversion to my Strada. For me, to buy a Silvio meant the Strada would have to go. After riding the conversion for only a week, I went back to the Strada. I rode it once and the answer became obvious. I put the Strada up for sale and the rest, as they say, is history.

Mark

 

[Doug Burton]

Mark... (jeez, everyone in this thread is named Mark...)

Jeebus...

if you measure from the BB axle centerline to the "flat" section where the two seat shell halves meet, what is that distance?

There's an adapter in development to address this problem, but I was able to make one for testing that works pretty well.

Being able to compare your TFT setting to mine will tell me if you'll need an adapter or not.

Best,

 

[jeebus]

To Mark: you mean the thing with the inch long hole where you can attach the derailler anywhere along it right? It's currently at the edge furthest from the bottom bracket in the direction toward the handlebars. If we call that the southernmost setting, it actually might be possible to go a hair farther south but not much. But that would make the bottom of the derailler cage even more likely to hit the chain. And I couldn't move it north by much either and still clear the large ring.

To Doug: as near as I can measure it it's 34.75". That's to the line that makes the beginning of the flat inch on the seat.

I am looking forward to the adapter, but this is the middle chain ring I'm talking about. Can the angle really be that far off? I would post a pic to see if I've got anything setup wrong but I haven't looked into how to post a pic on the forum yet.

- Mark

 

[jeebus]

The cranks it came with are 170mm.. is everybody else using shorter cranks or something?

- Mark

 

[defjack]

Your derailer should work ok with the 39.Why dont you email a picture to Doug.That would help alot. Jack

 

[jeebus]

Okay, I wasn't sure what all shots might be useful so just took a handful. First 3 pics:

 

[jeebus]

And three more. Forgot to mention, I kept the chain under tension for all the pics.

 

[jeebus]

Arghh, now that I've used up a few Mb of cruzbike's bandwidth, I just noticed there are two more holes down there that the derailler can be attached to instead of the top two. So, um, I think I know what needs to be done now. Jeez.

- Mark

 

[Mark B]

jeebus wrote: Arghh, now that I've used up a few Mb of cruzbike's bandwidth, I just noticed there are two more holes down there that the derailler can be attached to instead of the top two. So, um, I think I know what needs to be done now. Jeez.

- Mark

That was my question that obviously wasn't so stupid. I got a hunch your problem is solved. Don't feel bad; I did the same thing.

Mark

 

[Doug Burton]

Yep, the pictures are worth a thousand GB...

You might also take a look at the clearance between the derailleur cage and the large chainring at the point where the red arrow sticker is. The pictures make it look like it might be a little generous, but that might just be me. I usually set that at 2mm or so...

... but I think you have the principal issue solved - that dimension you took is 32 inches on my bike, so you should have operating clearance at 34.75. The crank length of choice seems to be 170mm, although that's not universal.

And eat up the bandwidth anytime. That's what it's for and we all learn when stuff comes here.

Enjoy your road rocket!

Best,

 

[Mark B]

Hardtailcruzer wrote: Yep, the pictures are worth a thousand GB...

I would like to point out that I called out the problem without benifit of said pictures... :lol: :lol: :lol: Of course, I also recognized the symptoms from having done the same thing myself.

Pics really do help, though!

Mark