gearing choice

[drshuf]

I finally decided to move up to silvio. I've ordered the frame and am planning to take as many components off my road bike to build out the Silvio.
I'm wondering if you can comment on any changes I may need:
My road bike is a Giant OCR2. The brifters are Shimano 105s as are the deraillers. I have a 9 speed cassette of 12 to 27 currently, but I'm thinking I need to go to the 11-32 or 34 that some have recommended on this board because of the steep hills in our area.

The crankset is a suigo? 52,42,30 which I assume should work, and I'm also assuming the front derailleur will work.
If I change cassettes, will I need a new rear derailleur, and if so, which one would you recommend that will work with the shimano brifters.

I plan to use the 700c wheels and brakes from the Giant bike (forgot to look at the name)
I'm ordering the wtb handlebar

Anything I'm missing? I'ld like to have the components all ready and take them to the LBS for assembly.

Looking forward to see what kind of performance gains will be actualized with this bike over the sofrider II.

Thanks
Reid

 

[Mark B]

Great move! I think you'll be really happy.

For me, I would be happy with a 12-27. I'm running a 12-23 right now and that's a smidgen too tall. I think it will be OK when I lose some more weight and get stronger, but I still might go to a bigger cassette.

For a rear derailleur, I would assume you'll be talking a mountain bike derailleur. If you go XTR, you will to double check it's compatible with your brifters because I think some of them are not.

Mark

 

[Doug Burton]

Hi Reid,

The bike is not really designed for a triple. That being said, if you are tall enough, a triple will work. People with a short x-seam will experience chain interference with the derailleur on the lowest chainring using a 52-42-30 crankset. My x-seam on this bike is about 40 inches, and I require an adapter to use a compact double.

A triple adapter bracket is in development to address this issue.

The SIlvio uses a braze-on front derailleur, so you may need to replace the one on your Giant. Shimano offers many high-quality, low cost braze-on derailleurs, especially for 9-speed systems.

Please bring all questions you may have.

Best,

 

[drshuf]

Hi Doug,
I'm 6' tall, when I measure from my hip joint to my heel, I'm measuring about 40 in x seam. Do you think this will not allow for the triple ring? That would suck, as I put a triple on my sofrider and it has made hills much more manageable.

Will the shimano 105 shifters accomodate a 10 speed cassette?
Will I need to change the rear derailleur?
Do you think the 11 to 34 is too much range in the cassette. I find on these long hill climbs in our area that I'm often in the 1st and 2nd gears on my sofrider which I think has a 32.

Thanks for the input.
Reid

 

[Mark B]

drshuf wrote: Hi Doug,
I'm 6' tall, when I measure from my hip joint to my heel, I'm measuring about 40 in x seam. Do you think this will not allow for the triple ring? That would suck, as I put a triple on my sofrider and it has made hills much more manageable.

Will the shimano 105 shifters accomodate a 10 speed cassette?
Will I need to change the rear derailleur?
Do you think the 11 to 34 is too much range in the cassette. I find on these long hill climbs in our area that I'm often in the 1st and 2nd gears on my sofrider which I think has a 32.

Thanks for the input.
Reid

I'm not Doug, but here's my take;

I'm 6' and I run a triple with no troubles. If we can make the connection this weekend, you can try my bike and see for sure.

9 speed shifters will not shift a 10 speed cassette.

It sounds like you will need a mountain bike cassette and derailleur, in which case you are definitely limited to 9 speed, anyway.

I can imagine how excited you must be at this point. I was downright giddy. Still am, kind of..

Mark

 

[xkred27]

drshuf wrote: I have a 9 speed cassette of 12 to 27 currently, but I'm thinking I need to go to the 11-32 or 34 that some have recommended on this board because of the steep hills in our area.

Reid,

I've had my Silvio for about a month now. I'm 5'10" w/ a 42-3" x-seam and am running a Shimano 105 52-42-30 triple no problem--in any gear. I mean no problem shifting. I'm running a 12-30 in the back and definitely don't have enough bottom, so later today am going to have Nanda swap out the 30 for a 26 granny. That, 25 fewer pounds, and a few more months in the saddle should do the trick. If not, I'll swap out the front end for a Sugino 48-38-24, or some such.

 

[drshuf]

Peter,
Since I have a 52,42,30 triple already ,would I get a similar advantage by using an 11-32 or 11-34. Sounds like a cheaper way to get around it for more lower gear range?
Thanks
Reid

 

[Doug Burton]

Hi Reid,

If you are running a triple on your Sofrider with no issues, you should be able to use a triple on your Silvio. Generally 6' riders don't have a problem. I'm 5'6" and the TFT is close to its minimum adjustment, making the chainstay angle nearly 90 degrees. This means I need an adapter to take 24 degrees out of the chainstay angle. I've built a prototype adapter to test this, and aside from being ugly, it works fine.

If you have a chance to ride Mark's bike, that is the best way to check everything out. I would suggest measuring the distance from the upper TFT clamp to the handlebar clamp, and the distance from the TFT clamp to the bottom bracket on Mark's bike, if it fits you. That will save you some setup time when you first get the bike together.

There are no real long cage derailleurs for Shimano 10 speed cassettes. That being said, sometimes the 9-speed long-cage derailleurs have enough extra travel to work with a 10-speed shifter. The 10-speed Shimano cassette spaces the cassette cogs closer together than the 9-speed cassette, so the 9-speed derailleur can usually cover the 10-speed cassette's displacement range. If you use an 11-34 cassette, you will need a long-cage derailleur to take up the chain slack, especially if you want to be able to use the bike in a crossover gear (big ring and big rear cog, for example). this only happens when you make a shifting error, but sometimes you don't want to do a lot to recover an error on a hill if you're hangin' with the big dogs on a group ride.

I am really trying to avoid having folks be dissapointed because they can't run the gearing they want due to their height. That was the purpose of my initial response to you. Sounds like you will have a nice bike when you're done.

Be well.

 

[defjack]

I started out with a 11-25 and a 39-52 but it was hard to ride the hills.Next was 12-32 and a 30-42-52 that was plenty low but I liked the road 11-25 for its spacing so that went back on.Next week I'm going to try changing to a home brew compact triple 30-39-48.Most of the time I'm riding in the 42 so the 52 is kind of high for my type of riding anyway. Jack

 

[xkred27]

drshuf wrote: Peter,
Since I have a 52,42,30 triple already ,would I get a similar advantage by using an 11-32 or 11-34. Sounds like a cheaper way to get around it for more lower gear range?
Thanks
Reid

From a strictly gear inches perspective, my 26 granny chainring and 30 (largest) cog gives me 22.9 g.i. using a 700x25 tire. A 30 granny up front w/ a 34 largest cog (your proposed setup) in back gives you 23.3, so the bottoms are pretty close. The only reason I didn't go that route is b/c I had a donor bike w/ an Ultegra long cage RD, which can handle my 12-30 cassette, but not (at least I think not) an 11-34. So I spent about 80 bucks getting the cassette and the chainring. I could as easily have spent the money leaving the front intact and buying a derailer with the capacity to handle the 11-34, but I kinda like the spacing on the 12-30 (i.e., 12-13-15-17-19-21-24-27-30).